What is an expectation?

[bnhpct]

[From Bruce Nevin (20190825.18:12 ET)]

I agree that when all folks have is metaphors and hand-waving they usually assume that’s all you have. They may know no other way to attempt to do science.Â

Nasrudin was searching around on his hands and knees under a streetlight. His friend came along.Â

"What are you looking for, Mullah?"Â

“I’ve lost the key to my house.”

“Here, I’ll help you.”

After a while, the friend got tired of creeping and peering around.

“Are you sure you lost it here?”

“Oh no, I lost it over in that dark alley beside my house.”

“Then why are you looking for it here?”

“There’s more light here!”

A clever mathematical model has great appeal because of its clarity and precision. “There’s more light here!” The merely metaphorical relation of the model to phenomena may be satisfying and may actually be invisible as long as nobody has to test how the model actually performs. (That’s been the situation in linguistics.)

But nonetheless I think there are phenomena that we refer to with words like ‘expect’ and ‘expectation’, phenomena that we should be able to model.

For example, in sequence control, when control of one step of the sequence generates a reference for control of the next step, that reference could fairly be called an expectation, at least in some circumstances. In general, I think the informal terms ‘expect’ and ‘expectation’ cover diverse perceptions associated in memory with a currently controlled perception. Related to the conventional psych notion of ‘priming’. ‘Desire’ and ‘want’, terms that we associate with the reference value and the reference signal, are related but not the same as an expectation. They converge when the associated perceptions in memory and imagination would be described with words like “success” and “easy”.

···

/Bruce

On Sat, Aug 24, 2019 at 11:49 PM Warren Mansell csgnet@lists.illinois.edu wrote:

Begin forwarded message:

From: Warren Mansell wmansell@gmail.com
Date: 25 August 2019 at 04:49:17 BST
To: mmt-csg@mmtaylor.net
Subject: Re: Maybe this puts the S-R psychology to rest

Agreed, and it makes it one of our biggest challenges in arguing for the advantages of PCT…

On 23 Aug 2019, at 20:13, Martin Taylor (mmt-csg@mmtaylor.net via csgnet Mailing List) csgnet@lists.illinois.edu wrote:

[Martin Taylor 2019.08.23.14.58]

        From: Frank

Lenk [2019.08.23.12:54]

Â

        I ran across

this article explaining some recent neuroscience:Â https://www.quantamagazine.org/brains-speed-up-perception-by-guessing-whats-next-20190502/

Â

        The language

doesn’t match PCT, but it definitely supports the idea that
the internal state of the organism matters much more than
whatever stimulus the environment (or some researcher)
throws its way.

Â

        Some key

quotes:

Frank, the language in these quotes sounds to me very like the plan

of the Friston free-energy approach than PCT. The difference between
PCT and Friston is more in that Friston is based in control of
behaviour to fulfil expectation, as opposed to control of input to
fulfil the actors “will”. That may sound like a crucial difference,
but it’s actually more of a difference of interpretation than a
difference in the mathematics of what is proposed, because Friston’s
“control of output” actually maps into the structure of the
reorganized perceptual control hierarchy pretty well.

The quote “*        and

then you influence it [with expectation], and what it knows
emerges* .â€? Illustrates the convergence, since “what the
hierarchy knows” is a metaphor for the current state of the
reorganized hierarchy. But it has no “expectation”. It has
“reference values”. An external analyst who knows the current
state of reorganization could have an expectation of the effect of
whatever the hierarchy might do give some change of reference
value due to a disturbance change to a higher-level perception,
but the acting system does not, except as a metaphor.

  Metaphors are often useful, but can be, and often are, misleading.

In this case, I think the “expectation” metaphor has led the
Friston followers (and there are many more than there are
followers of PCT) astray.

  Martin

Â

        While

a dynamical systems approach to neuroscience is hardly new,
it’s been difficult to test and model. The way experts think
about basic sensory perception tends toward the
hierarchical: The cortex builds up and integrates features
to form perceptions, sending signals to other layers of the
network that integrate still more information until the
brain ultimately arrives at a decision or behavior.

        Not

so in this new work. Instead, the team’s results support a
different kind of processing in which “all of this happens
at the same time, and … ** before
the stimulus even arrives,**� said Leslie Kay , a
neuroscientist at the University of Chicago who focuses on
olfaction. “You learn stuff within a cortical area,� forming
a system of connected clusters to reflect that learning,
“and then you influence it [with expectation], and what it
knows emerges.� [emphasis added by FL]

…

        It

also highlights the need to move away from focusing on
single neurons that respond to particular cues, and toward
making internal states and dynamics more explicit in our
understanding of sensory networks — even for the most bbasic
sensory stimuli. “It’s much easier to say that a neuron
increases its firing rate,� said Anan
Moran ,
a neurobiologist at Tel Aviv University in Israel. But to
understand how organisms work, “you cannot account only for
the stimulus, ** but also
for the internal state**,� he added. [emphasis
added by FL]

Â

Â

Frank