behaviour (of sick animals): the control of...?

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when hhapping in a kind of emergency mode— could be seen as an unfortunatee by-product of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? What is the cybernetic aspect of sickness behaviour? Cheers, Alex

[Bruce Nevin 2018-03-04_20:31:58 ET]

Way too broad a generalization. There is no single particular observable phenomenon that could be called “behavior of sick animals.” Illness disturbs to various degrees the ability of diverse systems to control their inputs.Â

···

On Sun, Mar 4, 2018 at 5:12 PM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happinng in a kind of emergency mode— could be seen as an unfortunate by-pproduct of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? What is the cybernetic aspect of sickness behaviour? Cheers, Alex

[Martin Taylor 2018.03.04.23.09]

What do you mean by "sick"? Conversely, what do you mean by

“healthy” or “not sick”? In general, optimum functioning presumably means that all the
intrinsic variables are near their genetically determined reference
values, which probably implies that perceptual functions are working
well. Perfection not being achievable in either set of variables,
I’m guessing the there is high-dimensional scale of deviation from
optimum, such that the further you are from reference values in any
direction, the less healthy and more sick you are. Even if this conforms to what you mean by “sick” and “healthy”, I
would imagine that the precise description of a particular way of
being sick would help in suggesting what “behaviour” might occur.
Fever seems to be pretty common, but a re-set of the reference value
for body temperature is unlikely to be within the perceptual control
hierarchy. It might offer a clue as to the control of intrinsic
variables, but I would be more inclined to suspect it would have
something to do with the immensely complex network of homeostatic
loops in the biochemistry and microbiome of the body. That’s all a
long way of saying “I don’t have a clue”, at least until you make
the nature of your question a bit more precise.
Martin

···

On 2018/03/4 5:12 PM, Alex Gomez-Marin
wrote:

      Is

there any explicit PCT account of the behaviour of sick
animals/humans? Namely, behaviour —when happing in a kindd of
emergency mode— could be seen as an unfortunate by-producct of
the disease (“behavioural illusion”) or as an adaptive
strategy to overcome it. What would then be controlled? What
is the cybernetic aspect of sickness behaviour? Cheers, Alex

[Martin Taylor 2018.03.04.23.09]

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kind of emergenccy mode— could be seen as an unfortunate by-product of the disease ((“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables, I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree.

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

HB : Right.

 I think that more or less precise description of a particular way of being sick you can get if you visit a doctor. So I I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor,  he can make laboratory tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are near their genetically determined reference values.Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you make the nature of your question a bit more precise.

HB : Good thinking…J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability« of organisms. And Bill upgraded him enormously.  I would say that PCT is TOP general theory about how organisms function.

Boris

Martin

···

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Again, fair answers in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

Hart_1988 (1).pdf (3.56 MB)

···

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

Â

Â

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

Â

[Martin Taylor 2018.03.04.23.09]

Â

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing inn a kind of emergency mode— could be seen as an unfortunate by-produuct of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables, I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

Â

HB : Right. I agree.

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

Â

HB : Right.

 I think that more or less precise description of a particular way of being sick you can get if you visit a doctor. So I I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor,  he can make laboratory tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are near their genetically determined reference values. Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

Â

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you make the nature of your question a bit more precise.

Â

HB : Good thinking…J

Â

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

Â

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

Â

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Â

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability« of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Â

Boris

Martin

[Bruce Nevin 2018-03-05_08:45:05 ET]

Thank you for making your question less vague, Alex.Â

The author advances the hypothesis that “lethargy, depression, anorexia, and reduction in grooming” are ‘behaviors’ which constitute “an organized, evolved behavioral strategy to facilitate the role of fever in combating viral and bacterial infections. The sick individual is viewed as being at a life or death juncture and its behavior is an all-out effort to overcome the disease.”

“[L]ethargy, depression, anorexia, and reduction in grooming” are external observations that are defined negatively relative to ‘normal behavior’. Lethargy and depression can be evinced by an infinite range of possible observed ‘behaviors’, anorexia specifically by the infinitely variable subset of eating ‘behaviors’ characterized as such by their common purpose of maintaining variables such as blood sugar, and grooming likewise by another infinitely variable subset of ‘behaviors’. The observer sees less of them than the observer normally sees.

If we may be permitted to consider these observations in control theoretic terms, Alex, without being accused of quoting chapter and verse of holy writ, are not all these ‘behaviors’ means of controlling inputs that matter to the animal? And does it not appear that during sickness those variables are being controlled with lower gain than usual? (And, not to dwell too much on circularity of which the reader is expected to be oblivious, are these not the observational signs by which we perceive that the animal is sick?)

Why would they be controlled with lower gain during sickness? A restatement of the author’s hypothesis is that genetically inherited innate control systems are controlling essential intracorporal states with high gain. The means for controlling those variables are therefore preoccupied and less available as means for controlling other variables.

This reframing of the hypothesis makes it potentially testable within a broader consideration of relative gain when multiple control systems have limited means of control in common at their disposal. (Example: I can’t type and eat my breakfast without the disposition of my hands and eyes alternating from one purpose to the other. And my cat just in from her venture out on this drizzly morning demands my attention too.)

···

On Mon, Mar 5, 2018 at 5:35 AM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Again, fair answers in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

Â

Â

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

Â

[Martin Taylor 2018.03.04.23.09]

Â

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kind of emergency mode— co could be seen as an unfortunate by-product of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables, I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

Â

HB : Right. I agree.

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

Â

HB : Right.

 I think that more or less precise description of a particular way of being sick you can get if you visit a doctor. So I I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor,  he can make laboratory tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are near their genetically determined reference values. Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

Â

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you make the nature of your question a bit more precise.

Â

HB : Good thinking…J

Â

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

Â

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

Â

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Â

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability« of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Â

Boris

Martin

[Martin Taylor 2018.03.05.10.12]

Why would you expect that? I ask this in the spirit of your enquiry

about sickness “behaviour”, except that here we have a specific
instance of “expectation”, which might be amenable to a specific
analysis.
Had you quoted the first paragraph of the Hart paper along with your
original question, you would have given the CSGnet community
something to chew on. Now we have the opportunity to see what you
are asking, and an understanding of the question offers a
possibility that some answer(s) may be forthcoming. Maybe I will
have an idea, maybe I won’t. But at least I now have an opportunity
to be relevant.
Martin

···

On 2018/03/5 5:35 AM, Alex Gomez-Marin
wrote:

      Again,

fair answers in general, but when the rubber
meets the road… I mean in the light of this paper
(attached). The idea that, when fever quicks in, animals shall
display some behaviours that are typically and clearly
characteristic of sick animals, and that those behaviours are
not simply by-products of shitting going on but actual
adaptive strategies to cope with the infection. But again, I
can’t expect more than a bunch of emails re-quoting the ten
commandments… Agh…

You are right, Martin. I value your answers and I could have been more detailed in my questions.

···

On Mon, Mar 5, 2018 at 4:20 PM, Martin Taylor mmt-csg@mmtaylor.net wrote:

[Martin Taylor 2018.03.05.10.12]

  On 2018/03/5 5:35 AM, Alex Gomez-Marin

wrote:

      Again,

fair answers in general, but when the rubber
meets the road… I mean in the light of this paper
(attached). The idea that, when fever quicks in, animals shall
display some behaviours that are typically and clearly
characteristic of sick animals, and that those behaviours are
not simply by-products of shitting going on but actual
adaptive strategies to cope with the infection. But again, I
can’t expect more than a bunch of emails re-quoting the ten
commandments… Agh…

Why would you expect that? I ask this in the spirit of your enquiry

about sickness “behaviour”, except that here we have a specific
instance of “expectation”, which might be amenable to a specific
analysis.

Had you quoted the first paragraph of the Hart paper along with your

original question, you would have given the CSGnet community
something to chew on. Now we have the opportunity to see what you
are asking, and an understanding of the question offers a
possibility that some answer(s) may be forthcoming. Maybe I will
have an idea, maybe I won’t. But at least I now have an opportunity
to be relevant.

Martin

[From Bruce Abbott (2018.03.05.1250 EST)]

[Bruce Nevin 2018-03-05_08:45:05 ET]

Thank you for making your question less vague, Alex.

The author advances the hypothesis that “lethargy, depression, anorexia, and reduction in grooming” are ‘behaviors’ which constitute “an organized, evolved behavioral strategy to facilitate the role of fever in combating viral and bacterial infections. The sick individual is viewed as being at a life or death juncture and its behavior is an all-out effort to overcome the disease.”

“[L]ethargy, depression, anorexia, and reduction in grooming” are external observations that are defined negatively relative to ‘normal behavior’. Lethargy and depression can be evinced by an infinite range of possible observed ‘behaviors’, anorexia specifically by the infinitely variable subset of eating ‘behaviors’ characterized as such by their common purpose of maintaining variables such as blood sugar, and grooming likewise by another infinitely variable subset of ‘behaviors’. The observer sees less of them than the observer normally sees.

If we may be permitted to consider these observations in control theoretic terms, Alex, without being accused of quoting chapter and verse of holy writ, are not all these ‘behaviors’ means of controlling inputs that matter to the animal? And does it not appear that during sickness those variables are being controlled with lower gain than usual? (And, not to dwell too much on circularity of which the reader is expected to be oblivious, are these not the observational signs by which we perceive that the animal is sick?)

Lowering the (loop) gain of a control system does not cause it to stop controlling (unless the gain goes to zero), nor does it change the reference level for the controlled perception. It simply causes a weaker output for a given level of error. In a proportional control system a lower gain means that, against a constant disturbance, the controlled perception will stabilize at a value that is farther from the reference value than if the gain were higher.

This is not to say that a lowering of the gain could not be part of the process. However, there may be other kinds of changes. For example, the perception of nausea may arise, which the individual quickly learns is associated with vomiting, especially if food is eaten. Nausea is perceived as a very unpleasant state; consequently the individual controls for avoiding the consumption (or even the smell) of food, so as not to increase the intensity of nausea and/or trigger vomiting.

I suggested long ago on this forum that fever as a reaction to illness seems to come in two forms: a “dryâ€? fever in which the person fails to sweat and feels hot, and a “wetâ€? fever in which the person sweats profusely. From a control-theoretic point of view, the former may represent a raising of the body-temperature set point and the latter from an effect of the illness that acts as a disturbance to body temperature without changing the set point. In the former case, the raising of set point produces a body-temperature error that increases metabolic output to raise the body temperature. In the latter case, the disturbance raises body temperature, inducing the opposite kind of error – body temperature well above set point, and the output to counnter this disturbance is to induce perfuse sweating. Evaporation of the sweat cools the body, sometimes inducing chills and shivering.

Animals other than human ones exhibit changes in behavior when ill that may not be explained convincingly by a change in gain. For example, dogs often eat grass when ill, which then induces vomiting. This behavior may have evolved because of the association between poisoning and feeling unwell – inducing vomiting would be adaptive if what is causing the feelinng of illness is something recently ingested.

The lethargy that often accompanies illness may be adaptive in that it conserves energy at a time when the individual may not be eating. In addition, some infections seem to promote muscle spasms or weakness, and reducing activity may reduce the chances of injury under such conditions.

Why would they be controlled with lower gain during sickness? A restatement of the author’s hypothesis is that genetically inherited innate control systems are controlling essential intracorporal states with high gain. The means for controlling those variables are therefore preoccupied and less available as means for controlling other variables.

This reframing of the hypothesis makes it potentially testable within a broader consideration of relative gain when multiple control systems have limited means of control in common at their disposal. (Example: I can’t type and eat my breakfast without the disposition of my hands and eyes alternating from one purpose to the other. And my cat just in from her venture out on this drizzly morning demands my attention too.)

···

/Bruce

On Mon, Mar 5, 2018 at 5:35 AM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Again, fair answers in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

[Martin Taylor 2018.03.04.23.09]

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kind of emergency mode— could bd be seen as an unfortunate by-product of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables, I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

HB : Right.

I think that more or less precise description of a particular way of being sick you can get if you visit a doctor. So I I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor, he can make laboratory tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are near their genetically determined reference values. Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you make the nature of your question a bit more precise.

HB : Good thinking…J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability« of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Boris

Martin

[Eetu Pikkarainen 2018-03-06_04:54:26 UTC]

My experience from my own and family members’ fewer is that often when you get sick (flu etc.) is some occasion usually in the evening when tired you first start to feel cold, you shiver
and tremble and get all the cloths and blankets you can get and possibly like to drink something hot. But still feel like freezing. I interpret that this must be a consequence of the rising of the reference for the body temperature. This can be an evolved
functional pattern, because at least some viruses which are not connected to cells but are increasing and wandering in the body will be killed by the heat. The you can take Aspirin and / or get some sleep then after some hours you start to feel hot and you
start to sweat. This must be a sign that the reference for body temperature has decreased back to normal. These kind of two way cycles can repeat many times during on a flu or some other inflammation illness.

So I think there can be at least two kind of fever “behavior�: the “side effect warming� described by Martin and the “functional healing fever� described above. The two modes Bruce described
could be the two stages of the latter cycle or two types of the latter, or perhaps the “wet� fever is sometimes that what Martin meant.

Anyway very interesting topic. Organisms have always been under the threat of different sicknesses, which are disturbances for their normal controlling. So they must have developed ways
how to cope with them. Sad if we don’t yet have any medical scientists in PCT circles?

···

Eetu

Please, regard all my statements as questions,

no matter how they are formulated.

[From Bruce Abbott (2018.03.05.1250 EST)]

[Bruce Nevin 2018-03-05_08:45:05 ET]

Thank you for making your question less vague, Alex.

The author advances the hypothesis that “lethargy, depression, anorexia, and reduction in grooming” are ‘behaviors’ which constitute “an organized, evolved behavioral strategy to facilitate
the role of fever in combating viral and bacterial infections. The sick individual is viewed as being at a life or death juncture and its behavior is an all-out effort to overcome the disease.”

“[L]ethargy, depression, anorexia, and reduction in grooming” are external observations that are defined negatively relative to ‘normal behavior’. Lethargy and depression can be evinced by an
infinite range of possible observed ‘behaviors’, anorexia specifically by the infinitely variable subset of eating ‘behaviors’ characterized as such by their common purpose of maintaining variables such as blood sugar, and grooming likewise by another infinitely
variable subset of ‘behaviors’. The observer sees less of them than the observer normally sees.

If we may be permitted to consider these observations in control theoretic terms, Alex, without being accused of quoting chapter and verse of holy writ, are not all these ‘behaviors’ means of
controlling inputs that matter to the animal? And does it not appear that during sickness those variables are being controlled with lower gain than usual? (And, not to dwell too much on circularity of which the reader is expected to be oblivious, are these
not the observational signs by which we perceive that the animal is sick?)

Lowering the (loop) gain of a control system does not cause it to stop controlling (unless the gain goes to zero), nor does it change the reference level for the controlled perception. It simply causes a weaker output
for a given level of error. In a proportional control system a lower gain means that, against a constant disturbance, the controlled perception will stabilize at a value that is farther from the reference value than if the gain were higher.

This is not to say that a lowering of the gain could not be part of the process. However, there may be other kinds of changes. For example, the perception of nausea may arise, which the individual quickly learns is
associated with vomiting, especially if food is eaten. Nausea is perceived as a very unpleasant state; consequently the individual controls for avoiding the consumption (or even the smell) of food, so as not to increase the intensity of nausea and/or trigger
vomiting.

I suggested long ago on this forum that fever as a reaction to illness seems to come in two forms: a “dry� fever in which the person fails to sweat and feels hot, and a “wet� fever in which the person sweats profusely.
From a control-theoretic point of view, the former may represent a raising of the body-temperature set point and the latter from an effect of the illness that acts as a disturbance to body temperature without changing the set point. In the former case, the
raising of set point produces a body-temperature error that increases metabolic output to raise the body temperature. In the latter case, the disturbance raises body temperature, inducing the opposite kind of error – body temperaturee well above set point,
and the output to counter this disturbance is to induce perfuse sweating. Evaporation of the sweat cools the body, sometimes inducing chills and shivering.

Animals other than human ones exhibit changes in behavior when ill that may not be explained convincingly by a change in gain. For example, dogs often eat grass when ill, which then induces vomiting. This behavior may
have evolved because of the association between poisoning and feeling unwell – inducing vomiting would be adaptive if what is causing the feeling of illness is something recently ingested.

The lethargy that often accompanies illness may be adaptive in that it conserves energy at a time when the individual may not be eating. In addition, some infections seem to promote muscle spasms or weakness, and reducing
activity may reduce the chances of injury under such conditions.

Why would they be controlled with lower gain during sickness? A restatement of the author’s hypothesis is that genetically inherited innate control systems are controlling essential intracorporal
states with high gain. The means for controlling those variables are therefore preoccupied and less available as means for controlling other variables.

This reframing of the hypothesis makes it potentially testable within a broader consideration of relative gain when multiple control systems have limited means of control in common at their
disposal. (Example: I can’t type and eat my breakfast without the disposition of my hands and eyes alternating from one purpose to the other. And my cat just in from her venture out on this drizzly morning demands my attention too.)

/Bruce

On Mon, Mar 5, 2018 at 5:35 AM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Again, fair answers
in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that
those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

[Martin Taylor 2018.03.04.23.09]

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kiind of emergency mode— could be seen as an uunfortunate by-product of the disease (“behavioural
illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables,
I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

HB : Right.

I think that more or less precise
description of a particular way of being sick you can get if you visit a doctor. So I
I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor, he can make laboratory tests which show
the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are
near their genetically determined reference values.
Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic
variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you
make the nature of your question a bit more precise.

HB : Good thinking…J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how
organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability«
of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Boris

Martin

[Martin Taylor 2018.03.06.00.58]

···

Both Eetu and Bruce hypothesized that
as part of the syndrome of sickness effects the reference value
for blood temperature might vary. To make your hypothesis
functional, you need a source for this variation of the reference
value. In the perceptual control hierarchy, reference variation is
always a consequence of changing output from a higher-level
control unit. The temperature control unit is presumably not in
the perceptual control hierarchy. At least so far as I know,
nobody has suggested that it is not an intrinsic variable.

  My guesses as to what might be happening used the temperature

control unit as a top-level intrinsic control unit, and the
lassitude was a natural effect of output variation to balance
energy dissipation and keep the temperature at its (fixed)
genetically set reference value. Do you (Eetu and Bruce) have a
hypothesis as to where the varying reference value comes from, and
why it should come from there in an evolutionary sense?

  Martin
        [Eetu

Pikkarainen 2018-03-06_04:54:26 UTC]

Â

        My experience from my own and family members’

fewer is that often when you get sick (flu etc.) is some
occasion usually in the evening when tired you first start
to feel cold, you shiver and tremble and get all the cloths
and blankets you can get and possibly like to drink
something hot. But still feel like freezing. I interpret
that this must be a consequence of the rising of the
reference for the body temperature. This can be an evolved
functional pattern, because at least some viruses which are
not connected to cells but are increasing and wandering in
the body will be killed by the heat. The you can take
Aspirin and / or get some sleep then after some hours you
start to feel hot and you start to sweat. This must be a
sign that the reference for body temperature has decreased
back to normal. These kind of two way cycles can repeat many
times during on a flu or some other inflammation illness.

Â

        So I think there can be at least two kind of

fever “behavior�: the “side effect warming� described by
Martin and the “functional healing fever� described above.
The two modes Bruce described could be the two stages of the
latter cycle or two types of the latter, or perhaps the
“wet� fever is sometimes that what Martin meant.

Â

        Anyway very interesting topic. Organisms have

always been under the threat of different sicknesses, which
are disturbances for their normal controlling. So they must
have developed ways how to cope with them. Sad if we don’t
yet have any medical scientists in PCT circles?

Â

Eetu

Â

          Â  Please, regard all my statements as

questions,

 no matter how they are formulated.

Â

Â

        [From Bruce Abbott

(2018.03.05.1250 EST)]

Â

[Bruce Nevin 2018-03-05_08:45:05 ET]

Â

              Thank you for making your question less

vague, Alex.Â

Â

              The author advances the hypothesis that

“lethargy, depression, anorexia, and reduction in
grooming” are ‘behaviors’ which constitute “an
organized, evolved behavioral strategy to facilitate
the role of fever in combating viral and bacterial
infections. The sick individual is viewed as being at
a life or death juncture and its behavior is an
all-out effort to overcome the disease.”

Â

              "[L]ethargy, depression, anorexia, and

reduction in grooming" are external observations that
are defined negatively relative to ‘normal behavior’.
Lethargy and depression can be evinced by an infinite
range of possible observed ‘behaviors’, anorexia
specifically by the infinitely variable subset of
eating ‘behaviors’ characterized as such by their
common purpose of maintaining variables such as blood
sugar, and grooming likewise by another infinitely
variable subset of ‘behaviors’. The observer sees less
of them than the observer normally sees.

Â

              If we may be permitted to consider these

observations in control theoretic terms, Alex, without
being accused of quoting chapter and verse of holy
writ, are not all these ‘behaviors’ means of
controlling inputs that matter to the animal? And does
it not appear that during sickness those variables are
being controlled with lower gain than usual? (And, not
to dwell too much on circularity of which the reader
is expected to be oblivious, are these not the
observational signs by which we perceive that the
animal is sick?)

Â

              Lowering the

(loop) gain of a control system does not cause it to
stop controlling (unless the gain goes to zero), nor
does it change the reference level for the controlled
perception. It simply causes a weaker output for a
given level of error. In a proportional control
system a lower gain means that, against a constant
disturbance, the controlled perception will stabilize
at a value that is farther from the reference value
than if the gain were higher.

Â

              This is not to say

that a lowering of the gain could not be part of the
process. However, there may be other kinds of
changes. For example, the perception of nausea may
arise, which the individual quickly learns is
associated with vomiting, especially if food is
eaten. Nausea is perceived as a very unpleasant
state; consequently the individual controls for
avoiding the consumption (or even the smell) of food,
so as not to increase the intensity of nausea and/or
trigger vomiting.

Â

              I suggested long

ago on this forum that fever as a reaction to illness
seems to come in two forms: a “dry� fever in which the
person fails to sweat and feels hot, and a “wet� fever
in which the person sweats profusely. From a
control-theoretic point of view, the former may
represent a raising of the body-temperature set point
and the latter from an effect of the illness that acts
as a disturbance to body temperature without changing
the set point. In the former case, the raising of set
point produces a body-temperature error that increases
metabolic output to raise the body temperature. In
the latter case, the disturbance raises body
temperature, inducing the opposite kind of error –
body temperature well above set point, and the output
to counter this disturbance is to induce perfuse
sweating. Evaporation of the sweat cools the body,
sometimes inducing chills and shivering.

Â

              Animals other than

human ones exhibit changes in behavior when ill that
may not be explained convincingly by a change in
gain. For example, dogs often eat grass when ill,
which then induces vomiting. This behavior may have
evolved because of the association between poisoning
and feeling unwell – inducing vomiting would be
adaptive if what is causing the feeling of illness is
something recently ingested.

Â

              The lethargy that

often accompanies illness may be adaptive in that it
conserves energy at a time when the individual may not
be eating. In addition, some infections seem to
promote muscle spasms or weakness, and reducing
activity may reduce the chances of injury under such
conditions.

Â

              Why would they be controlled with lower

gain during sickness? A restatement of the author’s
hypothesis is that genetically inherited innate
control systems are controlling essential
intracorporal states with high gain. The means for
controlling those variables are therefore preoccupied
and less available as means for controlling other
variables.

Â

            This reframing of the hypothesis makes it

potentially testable within a broader consideration of
relative gain when multiple control systems haveÂ
limited means of control in common at their disposal.
(Example: I can’t type and eat my breakfast without the
disposition of my hands and eyes alternating from one
purpose to the other. And my cat just in from her
venture out on this drizzly morning demands my attention
too.)

Â

/Bruce

Â

Â

            On Mon, Mar 5, 2018 at 5:35 AM, Alex

Gomez-Marin <agomezmarin@gmail.com >
wrote:

                  Again, fair answers

in general, but when the rubber
meets the road… I mean in the light of this
paper (attached). The idea that, when fever quicks
in, animals shall display some behaviours that are
typically and clearly characteristic of sick
animals, and that those behaviours are not simply
by-products of shitting going on but actual
adaptive strategies to cope with the infection.
But again, I can’t expect more than a bunch of
emails re-quoting the ten commandments… Agh…

Â

Â

                        On Mon, Mar 5, 2018 at 8:43 AM,

Boris Hartman <boris.hartman@masicom.net >
wrote:

Â

Â

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net ]
Sent: Monday, March 05,
2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of
sick animals): the control of…?

Â

                              [Martin Taylor

2018.03.04.23.09]

Â

                                On 2018/03/4 5:12 PM, Alex

Gomez-Marin wrote:

                                    Is there

any explicit PCT account of the
behaviour of sick
animals/humans? Namely,
behaviour —when happing in a
kind of emergency mode— couuld be
seen as an unfortunate
by-product of the disease
(“behavioural illusion”) or as
an adaptive strategy to overcome
it. What would then be
controlled? Cheers, Alex

                              What do you mean by "sick"?

Conversely, what do you mean by
“healthy” or “not sick”?

                              In general, optimum functioning

presumably means that all the
intrinsic variables are near their
genetically determined reference
values, which probably implies that
perceptual functions are working well.
Perfection not being achievable in
either set of variables, I’m guessing
the there is high-dimensional scale of
deviation from optimum, such that the
further you are from reference values
in any direction, the less healthy and
more sick you are.

Â

                              HB :

Right. I agree

                              MT :                                   Even

if this conforms to what you mean by
“sick” and “healthy”, I would imagine
that the precise description of a
particular way of being sick would
help in suggesting what “behaviour”
might occur.

Â

                              HB :

Right.

                              Â I

think that more or less precise
description of a particular way
of being sick you can get if you visit
a doctor. So I
I’ll guess
that terms »sick« and »healthy« are
usually somehow connected with
medicine. If you think that you are
sick you usually think of seeing a
doctor. If you decide to go to a
doctor, Â he can make laboratory
tests which show the state of some
»intrinsic variables«, so that he
can conclude how »intrinsic
variables« are
near their genetically
determined reference values.
Just as Martin wrote. Doctor will
try to make diagnosis and the way of
treatment to get you back in healthy
state (intrinsic variables back in
their genetically determind limits).

Â

MT : Fever
seems to be pretty common, but a
re-set of the reference value for body
temperature is unlikely to be within
the perceptual control hierarchy. It
might offer a clue as to the control
of intrinsic variables, but I would be
more inclined to suspect it would have
something to do with the immensely
complex network of homeostatic loops
in the biochemistry and microbiome of
the body. That’s all a long way of
saying “I don’t have a clue”, at least
until you make the nature of your
question a bit more precise.

Â

                              HB :

Good thinking…J

Â

                              AGM : What

is the cybernetic aspect of sickness
behaviour?

                                                                  Bill P

(B:CP) :

                              CONTROL

: Achievement and maintenance of a
preselected state in the controlling
system, through actions on the
environment that also cancel the
effects of disturbances

Â

                              HB :

You can understand that viruses or
bacterias or any other microorganism
that enters the body are
»disturbances« upon which imune
sub-system counteract with control
physiological mechanisms so to
maintain homeostasis.

Â

                              You

have to understand how orgsnism
function to determine what kind of
behavior you are observing. Even if
doctors don’t have laboratorical tests
they try to match observed »ilness« in
behavior with their knowledge of how
organisms function (their study) and
their experiences. This is more risky
method than laboratory tests as they
can imagine wrong and can make mistake
in diagnosis.

Â

                              Organisms

function in control manner and the
cybernetic approch is quite well
described in PCT. You could read in
any physiological book about the
basics of how organisms function.
Ashby started from this point with
»ultrastability« of organisms. And
Bill upgraded him enormously. I would
say that PCT is TOP general theory
about how organisms function.

Â

Boris

                              Martin

Â

Â

[Eetu Pikkarainen 2018-03-06_06:16:32 UTC]

image001143.png

···

Good point, Martin. Actually I think I have a very vague and wild hypothesis or at least some initial speculations. It goes shortly that also intrinsic varables form a hierarchy – no suggesstion
what kind it is, but perhaps those examples like body temperature, blood clugose level and oxygen level etc. are kind of basic level variable and bove them there are combined variables and the highest one is some kind of general systematic “well being� of
the organism. Disturbances to some basic level intrinsic variables can change the balance of the general well being and it can be sometimes controlled by changing the reference values of some other basic level intrinsic variables.

(The changes of all or some of these basic level intrinsic variables will affect the basic level units – mainly by caausing disturbances to their perceptions. So these two parallel hierachies are
conneted in the bottom. Below is is quick and dirty image about this quick and dirty thought.)

Eetu

Please, regard all my statements as questions,

no matter how they are formulated.

[Martin Taylor 2018.03.06.00.58]

Both Eetu and Bruce hypothesized that as part of the syndrome of sickness effects the reference value for blood temperature might vary. To make your hypothesis functional, you need a source for this variation
of the reference value. In the perceptual control hierarchy, reference variation is always a consequence of changing output from a higher-level control unit. The temperature control unit is presumably not in the perceptual control hierarchy. At least so far
as I know, nobody has suggested that it is not an intrinsic variable.

My guesses as to what might be happening used the temperature control unit as a top-level intrinsic control unit, and the lassitude was a natural effect of output variation to balance energy dissipation and keep the temperature at its (fixed) genetically set
reference value. Do you (Eetu and Bruce) have a hypothesis as to where the varying reference value comes from, and why it should come from there in an evolutionary sense?

Martin

[Eetu Pikkarainen 2018-03-06_04:54:26 UTC]

My experience from my own and family members’ fewer is that often when you get sick (flu etc.) is some occasion usually in the evening when tired you first start to feel cold, you shiver
and tremble and get all the cloths and blankets you can get and possibly like to drink something hot. But still feel like freezing. I interpret that this must be a consequence of the rising of the reference for the body temperature. This can be an evolved
functional pattern, because at least some viruses which are not connected to cells but are increasing and wandering in the body will be killed by the heat. The you can take Aspirin and / or get some sleep then after some hours you start to feel hot and you
start to sweat. This must be a sign that the reference for body temperature has decreased back to normal. These kind of two way cycles can repeat many times during on a flu or some other inflammation illness.

So I think there can be at least two kind of fever “behavior�: the “side effect warming� described by Martin and the “functional healing fever� described above. The two modes Bruce described
could be the two stages of the latter cycle or two types of the latter, or perhaps the “wet� fever is sometimes that what Martin meant.

Anyway very interesting topic. Organisms have always been under the threat of different sicknesses, which are disturbances for their normal controlling. So they must have developed ways
how to cope with them. Sad if we don’t yet have any medical scientists in PCT circles?

Eetu

Please, regard all my statements as questions,

no matter how they are formulated.

[From Bruce Abbott (2018.03.05.1250 EST)]

[Bruce Nevin 2018-03-05_08:45:05 ET]

Thank you for making your question less vague, Alex.

The author advances the hypothesis that “lethargy, depression, anorexia, and reduction in grooming” are ‘behaviors’ which constitute “an organized, evolved behavioral strategy to facilitate
the role of fever in combating viral and bacterial infections. The sick individual is viewed as being at a life or death juncture and its behavior is an all-out effort to overcome the disease.”

“[L]ethargy, depression, anorexia, and reduction in grooming” are external observations that are defined negatively relative to ‘normal behavior’. Lethargy and depression can be evinced by an
infinite range of possible observed ‘behaviors’, anorexia specifically by the infinitely variable subset of eating ‘behaviors’ characterized as such by their common purpose of maintaining variables such as blood sugar, and grooming likewise by another infinitely
variable subset of ‘behaviors’. The observer sees less of them than the observer normally sees.

If we may be permitted to consider these observations in control theoretic terms, Alex, without being accused of quoting chapter and verse of holy writ, are not all these ‘behaviors’ means of
controlling inputs that matter to the animal? And does it not appear that during sickness those variables are being controlled with lower gain than usual? (And, not to dwell too much on circularity of which the reader is expected to be oblivious, are these
not the observational signs by which we perceive that the animal is sick?)

Lowering the (loop) gain of a control system does not cause it to stop controlling (unless the gain goes to zero), nor does it change the reference level for the controlled perception. It simply causes a weaker output
for a given level of error. In a proportional control system a lower gain means that, against a constant disturbance, the controlled perception will stabilize at a value that is farther from the reference value than if the gain were higher.

This is not to say that a lowering of the gain could not be part of the process. However, there may be other kinds of changes. For example, the perception of nausea may arise, which the individual quickly learns is
associated with vomiting, especially if food is eaten. Nausea is perceived as a very unpleasant state; consequently the individual controls for avoiding the consumption (or even the smell) of food, so as not to increase the intensity of nausea and/or trigger
vomiting.

I suggested long ago on this forum that fever as a reaction to illness seems to come in two forms: a “dry� fever in which the person fails to sweat and feels hot, and a “wet� fever in which the person sweats profusely.
From a control-theoretic point of view, the former may represent a raising of the body-temperature set point and the latter from an effect of the illness that acts as a disturbance to body temperature without changing the set point. In the former case, the
raising of set point produces a body-temperature error that increases metabolic output to raise the body temperature. In the latter case, the disturbance raises body temperature, inducing the opposite kind of error – bodyy temperature well above set point,
and the output to counter this disturbance is to induce perfuse sweating. Evaporation of the sweat cools the body, sometimes inducing chills and shivering.

Animals other than human ones exhibit changes in behavior when ill that may not be explained convincingly by a change in gain. For example, dogs often eat grass when ill, which then induces vomiting. This behavior may
have evolved because of the association between poisoning and feeling unwell – inducing vomiting would be adaaptive if what is causing the feeling of illness is something recently ingested.

The lethargy that often accompanies illness may be adaptive in that it conserves energy at a time when the individual may not be eating. In addition, some infections seem to promote muscle spasms or weakness, and reducing
activity may reduce the chances of injury under such conditions.

Why would they be controlled with lower gain during sickness? A restatement of the author’s hypothesis is that genetically inherited innate control systems are controlling essential intracorporal
states with high gain. The means for controlling those variables are therefore preoccupied and less available as means for controlling other variables.

This reframing of the hypothesis makes it potentially testable within a broader consideration of relative gain when multiple control systems have limited means of control in common at their
disposal. (Example: I can’t type and eat my breakfast without the disposition of my hands and eyes alternating from one purpose to the other. And my cat just in from her venture out on this drizzly morning demands my attention too.)

/Bruce

On Mon, Mar 5, 2018 at 5:35 AM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Again, fair answers
in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that
those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

[Martin Taylor 2018.03.04.23.09]

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happinng in a kind of emergency mode— could be seeen as an unfortunate by-product of the disease (“behavioural
illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables,
I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour”
might occur.

HB : Right.

I think that more or less precise
description of a particular way of being sick you can get if you visit a doctor. So I
I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor, he can make laboratory
tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are
near their genetically determined reference values.
Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue
as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t
have a clue”, at least until you make the nature of your question a bit more precise.

HB : Good thinking…J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how
organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability«
of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Boris

Martin

[Eetu Pikkarainen 2018-03-06_12:19:59 UTC]

Sorry I have to reply to myself and add two things. First an amended image:

image002101.png

RoP = Reorganization pressure. This the higher level connection between these two hierarchies.

CP = Condition perceptions, like pain, cold, tenderness, weakness, powerlessness, nausea, hunger, thirst etc.

image001143.png

···

Eetu

From: Eetu Pikkarainen [mailto:eetu.pikkarainen@oulu.fi]
Sent: Tuesday, March 6, 2018 8:52 AM
To: csgnet@lists.illinois.edu
Subject: RE: behaviour (of sick animals): the control of…?

[Eetu Pikkarainen 2018-03-06_06:16:32 UTC]

Good point, Martin. Actually I think I have a very vague and wild hypothesis or at least some initial speculations. It goes shortly that also intrinsic varables form a hierarchy – no suuggestion
what kind it is, but perhaps those examples like body temperature, blood clugose level and oxygen level etc. are kind of basic level variable and bove them there are combined variables and the highest one is some kind of general systematic “well being� of
the organism. Disturbances to some basic level intrinsic variables can change the balance of the general well being and it can be sometimes controlled by changing the reference values of some other basic level intrinsic variables.

(The changes of all or some of these basic level intrinsic variables will affect the basic level units – mainly bby causing disturbances to their perceptions. So these two parallel hierachies are
conneted in the bottom. Below is is quick and dirty image about this quick and dirty thought.)

Eetu

Please, regard all my statements as questions,

no matter how they are formulated.

[Martin Taylor 2018.03.06.00.58]

Both Eetu and Bruce hypothesized that as part of the syndrome of sickness effects the reference value for blood temperature might vary. To make your hypothesis functional, you need a source for this variation
of the reference value. In the perceptual control hierarchy, reference variation is always a consequence of changing output from a higher-level control unit. The temperature control unit is presumably not in the perceptual control hierarchy. At least so far
as I know, nobody has suggested that it is not an intrinsic variable.

My guesses as to what might be happening used the temperature control unit as a top-level intrinsic control unit, and the lassitude was a natural effect of output variation to balance energy dissipation and keep the temperature at its (fixed) genetically set
reference value. Do you (Eetu and Bruce) have a hypothesis as to where the varying reference value comes from, and why it should come from there in an evolutionary sense?

Martin

[Eetu Pikkarainen 2018-03-06_04:54:26 UTC]

My experience from my own and family members’ fewer is that often when you get sick (flu etc.) is some occasion usually in the evening when tired you first start to feel cold, you shiver
and tremble and get all the cloths and blankets you can get and possibly like to drink something hot. But still feel like freezing. I interpret that this must be a consequence of the rising of the reference for the body temperature. This can be an evolved
functional pattern, because at least some viruses which are not connected to cells but are increasing and wandering in the body will be killed by the heat. The you can take Aspirin and / or get some sleep then after some hours you start to feel hot and you
start to sweat. This must be a sign that the reference for body temperature has decreased back to normal. These kind of two way cycles can repeat many times during on a flu or some other inflammation illness.

So I think there can be at least two kind of fever “behavior�: the “side effect warming� described by Martin and the “functional healing fever� described above. The two modes Bruce described
could be the two stages of the latter cycle or two types of the latter, or perhaps the “wet� fever is sometimes that what Martin meant.

Anyway very interesting topic. Organisms have always been under the threat of different sicknesses, which are disturbances for their normal controlling. So they must have developed ways
how to cope with them. Sad if we don’t yet have any medical scientists in PCT circles?

Eetu

Please, regard all my statements as questions,

no matter how they are formulated.

[From Bruce Abbott (2018.03.05.1250 EST)]

[Bruce Nevin 2018-03-05_08:45:05 ET]

Thank you for making your question less vague, Alex.

The author advances the hypothesis that “lethargy, depression, anorexia, and reduction in grooming” are ‘behaviors’ which constitute “an organized, evolved behavioral strategy to facilitate
the role of fever in combating viral and bacterial infections. The sick individual is viewed as being at a life or death juncture and its behavior is an all-out effort to overcome the disease.”

“[L]ethargy, depression, anorexia, and reduction in grooming” are external observations that are defined negatively relative to ‘normal behavior’. Lethargy and depression can be evinced by an
infinite range of possible observed ‘behaviors’, anorexia specifically by the infinitely variable subset of eating ‘behaviors’ characterized as such by their common purpose of maintaining variables such as blood sugar, and grooming likewise by another infinitely
variable subset of ‘behaviors’. The observer sees less of them than the observer normally sees.

If we may be permitted to consider these observations in control theoretic terms, Alex, without being accused of quoting chapter and verse of holy writ, are not all these ‘behaviors’ means of
controlling inputs that matter to the animal? And does it not appear that during sickness those variables are being controlled with lower gain than usual? (And, not to dwell too much on circularity of which the reader is expected to be oblivious, are these
not the observational signs by which we perceive that the animal is sick?)

Lowering the (loop) gain of a control system does not cause it to stop controlling (unless the gain goes to zero), nor does it change the reference level for the controlled perception. It simply causes a weaker output
for a given level of error. In a proportional control system a lower gain means that, against a constant disturbance, the controlled perception will stabilize at a value that is farther from the reference value than if the gain were higher.

This is not to say that a lowering of the gain could not be part of the process. However, there may be other kinds of changes. For example, the perception of nausea may arise, which the individual quickly learns is
associated with vomiting, especially if food is eaten. Nausea is perceived as a very unpleasant state; consequently the individual controls for avoiding the consumption (or even the smell) of food, so as not to increase the intensity of nausea and/or trigger
vomiting.

I suggested long ago on this forum that fever as a reaction to illness seems to come in two forms: a “dry� fever in which the person fails to sweat and feels hot, and a “wet� fever in which the person sweats profusely.
From a control-theoretic point of view, the former may represent a raising of the body-temperature set point and the latter from an effect of the illness that acts as a disturbance to body temperature without changing the set point. In the former case, the
raising of set point produces a body-temperature error that increases metabolic output to raise the body temperature. In the latter case, the disturbance raises body temperature, inducing the opposite kind of error – body temperature well abovve set point,
and the output to counter this disturbance is to induce perfuse sweating. Evaporation of the sweat cools the body, sometimes inducing chills and shivering.

Animals other than human ones exhibit changes in behavior when ill that may not be explained convincingly by a change in gain. For example, dogs often eat grass when ill, which then induces vomiting. This behavior may
have evolved because of the association between poisoning and feeling unwell – inducinng vomiting would be adaptive if what is causing the feeling of illness is something recently ingested.

The lethargy that often accompanies illness may be adaptive in that it conserves energy at a time when the individual may not be eating. In addition, some infections seem to promote muscle spasms or weakness, and reducing
activity may reduce the chances of injury under such conditions.

Why would they be controlled with lower gain during sickness? A restatement of the author’s hypothesis is that genetically inherited innate control systems are controlling essential intracorporal
states with high gain. The means for controlling those variables are therefore preoccupied and less available as means for controlling other variables.

This reframing of the hypothesis makes it potentially testable within a broader consideration of relative gain when multiple control systems have limited means of control in common at their
disposal. (Example: I can’t type and eat my breakfast without the disposition of my hands and eyes alternating from one purpose to the other. And my cat just in from her venture out on this drizzly morning demands my attention too.)

/Bruce

On Mon, Mar 5, 2018 at 5:35 AM, Alex Gomez-Marin agomezmarin@gmail.com wrote:

Again, fair answers
in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that
those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

[Martin Taylor 2018.03.04.23.09]

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kind of emergenncy mode— could be seen as an unfortunate byy-product of the disease (“behavioural
illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables,
I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour”
might occur.

HB : Right.

I think that more or less precise
description of a particular way of being sick you can get if you visit a doctor. So I
I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor, he can make laboratory
tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are
near their genetically determined reference values.
Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue
as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t
have a clue”, at least until you make the nature of your question a bit more precise.

HB : Good thinking…¦J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how
organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability«
of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Boris

Martin

[From Bruce Abbott (2018.03.06.0935 EST)]

[Martin Taylor 2018.03.06.00.58]

Both Eetu and Bruce hypothesized that as part of the syndrome of sickness effects the reference value for blood temperature might vary. To make your hypothesis functional, you need a source for this variation of the reference value. In the perceptual control hierarchy, reference variation is always a consequence of changing output from a higher-level control unit. The temperature control unit is presumably not in the perceptual control hierarchy. At least so far as I know, nobody has suggested that it is not an intrinsic variable.

My guesses as to what might be happening used the temperature control unit as a top-level intrinsic control unit, and the lassitude was a natural effect of output variation to balance energy dissipation and keep the temperature at its (fixed) genetically set reference value. Do you (Eetu and Bruce) have a hypothesis as to where the varying reference value comes from, and why it should come from there in an evolutionary sense?

I must admit, the more I have thought about it, the less enamored I am of the concept of intrinsic variables. Yes, there are physiological variables, such as blood glucose level, blood oxygen level,  or body temperature, for which departures beyond certain values have rather dire consequences, but these levels are regulated just as any other controlled variables are. Some may have fixed reference levels selected through evolutionary processes, whereas others may have variable reference levels whose values are determined by (or at least can be altered somewhat by) inputs from other sources.

With respect to body temperature, there appears to be a “normal� reference value averaging around 98.6 degrees F (although recent measurements have indicated that it is actually a little higher). However, this reference is not actually fixed, but varies regularly as one component of the circadian (daily) rhythm.

When the body is attacked by viral or bacterial agents one common response is to raise the body temperature. Â This response is adaptive in that the higher temperatures appear to hinder or kill many kinds of infectious agent.

The hypothalamus contains structures involved in the regulation of body temperature, including blood temperature sensors, comparator, and neural links to output mechanisms. External disturbances arriving at the body surface act on temperature sensors in the skin, allowing the hypothalamic mechanism to begin to oppose them even before the core body temperature can change, but sustained gains or losses of heat that result in changes in core body temperature (and thus in blood temperature) can be sensed within the hypothalamus itself.

I would guess that the inputs that alter the reference level for body temperature during illness are not neural signals but biochemical ones. These signals might be generated by infected cells or their breakdown and delivered to the hypothalamus through the general circulation.

When we are not suffering from an illness, control over core body temperature is achieved through automatic physiological adjustments of certain output mechanisms. Signals from the periphery indicating a climbing skin temperature cause the system to activate the sweat glands on the skin, and the body’s metabolic rate may be dialed down a bit so that less heat is generated internally. Capillaries near the skin surface dilate, allowing the heat in the blood to reach the skin surface more readily, in effect reducing the insulating capacity of the skin. When skin temperature decreases, other output mechanisms come into play: shivering (which increases heat generation by the muscles), perhaps a raising of metabolic rate, and constriction of the capillaries near the skin surface, increasing the insulating capacity of the skin.

But there is another effect of such disturbances to skin (and body) temperature: We perceive ourselves to be hot or cold, and associated with these perceptions are feelings of discomfort. In effect we perceive the error; moreover, this error comes with a sensory tag – we know more than THAT something is wrong, we know WHAT is wrrong. At this point our learned control strategies come into play. When too hot we get out of the sun, sip a cold drink, seek out the air conditioning, remove excess clothing, reduce our activity level. When too cold we put on extra clothing, go into a heated room, sip a hot drink, run in place. In either case we continue until that feeling of discomfort abates.

I propose that we are equipped with the capacity to experience such deviations (including the associated feelings such as discomfort) so that we can learn how to deal effectively with them – i.e., to bring the variables in question under behavioral (as opposed to purely physiological) control.

Bruce

Dear Alex

···

From: Alex Gomez-Marin [mailto:agomezmarin@gmail.com]
Sent: Monday, March 05, 2018 11:35 AM
To: csgnet
Subject: Re: behaviour (of sick animals): the control of…?

Again, fair answers in general, but when the rubber meets the road… I mean in the light of this paper (attached). The idea that, when fever quicks in, animals shall display some behaviours that are typically and clearly characteristic of sick animals, and that those behaviours are not simply by-products of shitting going on but actual adaptive strategies to cope with the infection. But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

HB : Alex whatever you know about internal functioning of organism is here. You wrote it for yourself.

AGM : those behaviours are… actual adapttive strategies to cope with the infection.

HB : You just have to elaborate what means »actual adaptive strategies«. I’ll guess that by analyzing »strategies« you’ll come to the conclusion that whatever entered the organism caused organism to counteract intrusive organisms or control happens. So I suppose you’ll end at human control theory, because adaptive strategies you described are control nechanisms in organism. There are thousands of complex control units on some macro tissue level, but if you’ll go deeper into tissues you’ll see that there are again thousands more control units with local control which is synchronised in whole. And so on… PCT made very deep understanding of this simple fact of nature…Â

These are biological and physiological and if you want pathophysiological »facts« which help thousands and thousands of people survive every day on the Earth. Fact is for me something that we can perceive and control any time. Why phylosophy Alex ? There is real life out there. Problem is only who will give the best explanation that will have the best feet what is really happening.

I think that your problem is not in understanding what PCT is talking about, but sorry to say, it seems to me that you hate it. And that have nothing to do with science.Â

AGM : behaviours are not simply by-products of shitting going on… But again, I can’t expect more than a bunch of emails re-quoting the ten commandments… Agh…

HB : Your type of writing seems to show your emotional level of approcah to PCT. It seems that it has nothing to do with your biological, physiological erc. knowledge or understanding of PCT, about how organisms function.

Whatever you meant by 10 PCT commandments they are there outside in real life. They work. They explain real life. We conflict each other in many possible forms (including wars), we cooperate, we are angry when something goes wrong, and so on. We try to achieve our everyday and long term goals. And PCT explains all that succesfully.

But if you supply better explanation, I hope that biologists, physiologists, doctors will listen to you. But till then we have to live and the best way known today is that when you have a very high fever or you feel very bad, you visit a doctor. So if you don’t beleive PCT, you can meet some doctor to explain you the basics how you function or why you are ill. It’s no such big deal.

Best wishes,

Boris

On Mon, Mar 5, 2018 at 8:43 AM, Boris Hartman boris.hartman@masicom.net wrote:

From: Martin Taylor [mailto:mmt-csg@mmtaylor.net]
Sent: Monday, March 05, 2018 5:19 AM
To: csgnet@lists.illinois.edu
Subject: Re: behaviour (of sick animals): the control of…?

[Martin Taylor 2018.03.04.23.09]

On 2018/03/4 5:12 PM, Alex Gomez-Marin wrote:

Is there any explicit PCT account of the behaviour of sick animals/humans? Namely, behaviour —when happing in a kind of emergency mode— could be seeneen as an unfortunate by-product of the disease (“behavioural illusion”) or as an adaptive strategy to overcome it. What would then be controlled? Cheers, Alex

What do you mean by “sick”? Conversely, what do you mean by “healthy” or “not sick”?

In general, optimum functioning presumably means that all the intrinsic variables are near their genetically determined reference values, which probably implies that perceptual functions are working well. Perfection not being achievable in either set of variables, I’m guessing the there is high-dimensional scale of deviation from optimum, such that the further you are from reference values in any direction, the less healthy and more sick you are.

HB : Right. I agree.

MT : Even if this conforms to what you mean by “sick” and “healthy”, I would imagine that the precise description of a particular way of being sick would help in suggesting what “behaviour” might occur.

HB : Right.

I think that more or less precise description of a particular way of being sick you can get if you visit a doctor. So I I’ll guess that terms »sick« and »healthy« are usually somehow connected with medicine. If you think that you are sick you usually think of seeing a doctor. If you decide to go to a doctor, he can make laboratory tests which show the state of some »intrinsic variables«, so that he can conclude how »intrinsic variables« are near their genetically determined reference values. Just as Martin wrote. Doctor will try to make diagnosis and the way of treatment to get you back in healthy state (intrinsic variables back in their genetically determind limits).

MT : Fever seems to be pretty common, but a re-set of the reference value for body temperature is unlikely to be within the perceptual control hierarchy. It might offer a clue as to the control of intrinsic variables, but I would be more inclined to suspect it would have something to do with the immensely complex network of homeostatic loops in the biochemistry and microbiome of the body. That’s all a long way of saying “I don’t have a clue”, at least until you make the nature of your question a bit more precise.

HB : Good thinking…J

AGM : What is the cybernetic aspect of sickness behaviour?

Bill P (B:CP) :

CONTROL : Achievement and maintenance of a preselected state in the controlling system, through actions on the environment that also cancel the effects of disturbances

HB : You can understand that viruses or bacterias or any other microorganism that enters the body are »disturbances« upon which imune sub-system counteract with control physiological mechanisms so to maintain homeostasis.

You have to understand how orgsnism function to determine what kind of behavior you are observing. Even if doctors don’t have laboratorical tests they try to match observed »ilness« in behavior with their knowledge of how organisms function (their study) and their experiences. This is more risky method than laboratory tests as they can imagine wrong and can make mistake in diagnosis.

Organisms function in control manner and the cybernetic approch is quite well described in PCT. You could read in any physiological book about the basics of how organisms function. Ashby started from this point with »ultrastability« of organisms. And Bill upgraded him enormously. I would say that PCT is TOP general theory about how organisms function.

Boris

Martin