Your Fingertips Perform Brain-like Calculations

tedcloak · September 11, 2014, 3:42pm

From Human Ethology listserv:

···

[ Your

Fingertips Perform Brain-like Calculations ](https://groups.yahoo.com/neo/groups/human-ethology/conversations/topics/61157;_ylc=X3oDMTJzc3E0dnY4BF9TAzk3MzU5NzE1BGdycElkAzE5NDU5MzAzBGdycHNwSWQDMTcwNTA4MzEyNQRtc2dJZAM2MTE1NwRzZWMDZG1zZwRzbGsDdm1zZwRzdGltZQMxNDEwNDM5ODA0)

Thu Sep 11, 2014 5:49 am (PDT) . Posted by:

"Jay

Feierman" jrfeier

Your Fingertips Perform Brain-like Calculations

By Carl Engelking | September 8, 2014 2:54 pm

Your brain has a lot to think about, so if there’s a way to outsource a

few mental tasks to save bandwidth, it’s going to do it. Now researchers

have discovered another such workaround: the neurons in your fingertips

perform some computational tasks independently of the brain.

Researchers from Umeå University in Sweden demonstrated that nerve

endings in our fingertips encode information about touch intensity and

shape before those signals ever travel to the brain. Their findings

challenge the long-held belief that our skin simply signaled that

something was touched, and our brains processed all the bits of

information about shape.

Magic Touch

Pressure-sensing nerves in our fingertips come in two different flavors

– Meissner corpuscles and Merkel discs. Meissner corpuscles react to

light, fast deformations across the skin, and Merkel discs respond to

pressure and slower, deeper impressions on the skin. Researchers

hypothesized that these two nerve types worked in harmony to not just

pass along sensory info but to actually pre-process it before it reaches

the brain.

To test their theory, researchers used a rotating drum with raised edges

of various shapes to stimulate the fingertips of 44 volunteers. They

monitored neural impulses with an electrode, which was inserted into the

median nerve. The various edge shapes on the rotating drum caused

volunteers’ fingertip neurons to fire in varying levels of intensity and

frequency. Essentially, our fingertip neurons, in a similar fashion as

brain neurons, created a code that conveyed information about an edge’s

shape.

Clever Fingertips

Their findings, published Sunday in the journal Nature Neuroscience,

challenge the long-held belief that neurons in our cerebral cortex

performed all the calculations to process touch data. Researchers are

conducting more experiments to see if the same fingertip neurons can

sense an object’s curvature and direction of motion, which are also

typically considered a brain-based function.

Abbott · September 11, 2014, 6:21pm

[From Bruce Abbott (2014.09.11.1420 EDT)]

Thanks, Ted. Without seeing the published scientific report it’s a bit difficult to know whether the statements contained in the popular-press article by Carl Engelking accurately reflect what the study’s authors actually said about it, but I do have a quibble with what was stated in Engelking’s article. According to the article, “nerve endings in our fingertips encode information about touch intensity and shape . . .” and “the various edge shapes on the rotating drum caused volunteers’ fingertip neurons to fire in varying levels of intensity and frequency.” When neurons fire, they always fire at the same level of intensity (“all-or-none principle”). All that can vary is the frequency at which they fire. One can only speculate that the varying levels of intensity recorded from the median nerve reflect changes in the numbers of neurons in the nerve that are actively producing action potentials as well as their average frequency of firing, what Bill Powers referred to as the neural current. In what way do these variations supposedly “encode” edge shape? We will need to see the journal article to find out what the researchers had to say.

Bruce

···

From: csgnet-request@lists.illinois.edu [mailto:csgnet-request@lists.illinois.edu] On Behalf Of Ted Cloak
Sent: Thursday, September 11, 2014 11:43 AM
To: csgnet@lists.illinois.edu
Subject: Your Fingertips Perform Brain-like Calculations

From Human Ethology listserv:

Your Fingertips Perform Brain-like Calculations

Thu Sep 11, 2014 5:49 am (PDT) . Posted by:

“Jay Feierman” jrfeier

Your Fingertips Perform Brain-like Calculations
By Carl Engelking | September 8, 2014 2:54 pm

Your brain has a lot to think about, so if there’s a way to outsource a
few mental tasks to save bandwidth, it’s going to do it. Now researchers
have discovered another such workaround: the neurons in your fingertips
perform some computational tasks independently of the brain.

Researchers from Umeå University in Sweden demonstrated that nerve
endings in our fingertips encode information about touch intensity and
shape before those signals ever travel to the brain. Their findings
challenge the long-held belief that our skin simply signaled that
something was touched, and our brains processed all the bits of
information about shape.

Magic Touch
Pressure-sensing nerves in our fingertips come in two different flavors
– Meissner corpuscles and Merkel discs. Meissner corpuscles react to
light, fast deformations across the skin, and Merkel discs respond to
pressure and slower, deeper impressions on the skin. Researchers
hypothesized that these two nerve types worked in harmony to not just
pass along sensory info but to actually pre-process it before it reaches
the brain.

To test their theory, researchers used a rotating drum with raised edges
of various shapes to stimulate the fingertips of 44 volunteers. They
monitored neural impulses with an electrode, which was inserted into the
median nerve. The various edge shapes on the rotating drum caused
volunteers’ fingertip neurons to fire in varying levels of intensity and

frequency. Essentially, our fingertip neurons, in a similar fashion as
brain neurons, created a code that conveyed information about an edge’s
shape.

Clever Fingertips
Their findings, published Sunday in the journal Nature Neuroscience,
challenge the long-held belief that neurons in our cerebral cortex
performed all the calculations to process touch data. Researchers are
conducting more experiments to see if the same fingertip neurons can
sense an object’s curvature and direction of motion, which are also
typically considered a brain-based function.

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2014.0.4765 / Virus Database: 4015/8194 - Release Date: 09/11/14

tedcloak · September 11, 2014, 7:56pm

Funny. Feierman usually includes a reference to the original article, or to the source of his summary which would have a link to same. Ted

···

From: csgnet-request@lists.illinois.edu [mailto:csgnet-request@lists.illinois.edu]
On Behalf Of Bruce Abbott
Sent: Thursday, September 11, 2014 12:21 PM
To: csgnet@lists.illinois.edu
Subject: RE: Your Fingertips Perform Brain-like Calculations

[From Bruce Abbott (2014.09.11.1420 EDT)]

Thanks, Ted. Without seeing the published scientific report it’s a bit difficult to know whether the statements contained in the popular-press article by Carl Engelking accurately reflect what
the study’s authors actually said about it, but I do have a quibble with what was stated in Engelking’s article. According to the article, “nerve endings in our fingertips encode information about touch intensity and shape . . .” and “the various edge shapes
on the rotating drum caused volunteers’ fingertip neurons to fire in varying levels of intensity and frequency.” When neurons fire, they always fire at the same level of intensity (“all-or-none principle”). All that can vary is the frequency at which they
fire. One can only speculate that the varying levels of intensity recorded from the median nerve reflect changes in the numbers of neurons in the nerve that are actively producing action potentials as well as their average frequency of firing, what Bill Powers
referred to as the neural current. In what way do these variations supposedly “encode” edge shape? We will need to see the journal article to find out what the researchers had to say.

Bruce

From:
csgnet-request@lists.illinois.edu [mailto:csgnet-request@lists.illinois.edu]
On Behalf Of Ted Cloak
Sent: Thursday, September 11, 2014 11:43 AM
To: csgnet@lists.illinois.edu
Subject: Your Fingertips Perform Brain-like Calculations