Connectionists: Grandmother neurons

[Asim Roy]

Fred,

I have heard your arguments before. That's a fairly standard argument. You are ignoring neuroscience evidence. Remember that there is a long history of single cell recordings. And some of those studies led to Nobel prizes. Here's a list of some from Wikipedia: Single-unit recording - Wikipedia<https://en.wikipedia.org/wiki/Single-unit_recording>


  *   1928: One of the earliest accounts of being able to record from the nervous system was by Edgar Adrian<https://en.wikipedia.org/wiki/Edgar_Adrian> in his 1928 publication "The Basis of Sensation". In this, he describes his recordings of electrical discharges in single nerve fibers using a Lippmann electrometer<https://en.wikipedia.org/wiki/Lippmann_electrometer>. He won the Nobel Prize in 1932 for his work revealing the function of neurons.[11]<https://en.wikipedia.org/wiki/Single-unit_recording#cite_note-11>
  *   1957: John Eccles<https://en.wikipedia.org/wiki/John_Carew_Eccles> used intracellular single-unit recording to study synaptic mechanisms in motoneurons (for which he won the Nobel Prize in 1963).
  *   1959: Studies by David H. Hubel<https://en.wikipedia.org/wiki/David_H._Hubel> and Torsten Wiesel<https://en.wikipedia.org/wiki/Torsten_Wiesel>. They used single neuron recordings to map the visual cortex in unanesthesized, unrestrained cats using tungsten electrodes. This work won them the Nobel Prize in 1981 for information processing in the visual system.
  *   Moser and O'Keefe Nobel prize (grid and place cells): The 2014 Nobel Prize in Physiology or Medicine - Press release<https://www.nobelprize.org/prizes/medicine/2014/press-release/>

So you are questioning some ground-breaking work in this area. You might have an argument with the Nobel committee also. But take a hard look at the single-cell experiments first before you pick a fight with them.

By the way, the concept cell findings were verified with repeated experiments, something you expect in science. Take a look at the Reddy and Thorpe paper if you have not done so yet. Plus, bear in mind the Nobel prizes are not given on the basis of some fluke experiments. So, you are, in effect, arguing against the findings of Hubel and Wiesel and others.

Reddy, L., and Thorpe, S. J. (2014). Concept cells through associative learning of high-level representations. Neuron 84, 248-251. doi: 10.1016/j.neuron.2014.10.004


All the best,
Asim Roy
Professor, Information Systems
Arizona State University
Lifeboat Foundation Bios: Professor Asim Roy<https://urldefense.proofpoint.com/v2/url?u=https-3A__lifeboat.com_ex_bios.asim.roy&d=DwMFaQ&c=slrrB7dE8n7gBJbeO0g-IQ&r=wQR1NePCSj6dOGDD0r6B5Kn1fcNaTMg7tARe7TdEDqQ&m=waSKY67JF57IZXg30ysFB_R7OG9zoQwFwxyps6FbTa1Zh5mttxRot_t4N7mn68Pj&s=oDRJmXX22O8NcfqyLjyu4Ajmt8pcHWquTxYjeWahfuw&e=>
Asim Roy | iSearch (asu.edu)<https://urldefense.proofpoint.com/v2/url?u=https-3A__isearch.asu.edu_profile_9973&d=DwMFaQ&c=slrrB7dE8n7gBJbeO0g-IQ&r=wQR1NePCSj6dOGDD0r6B5Kn1fcNaTMg7tARe7TdEDqQ&m=waSKY67JF57IZXg30ysFB_R7OG9zoQwFwxyps6FbTa1Zh5mttxRot_t4N7mn68Pj&s=jCesWT7oGgX76_y7PFh4cCIQ-Ife-esGblJyrBiDlro&e=>


From: Connectionists <connectionists-bounces at mailman.srv.cs.cmu.edu> On Behalf Of Rothganger, Fred
Sent: Thursday, February 22, 2024 1:58 PM
To: connectionists at mailman.srv.cs.cmu.edu
Subject: Connectionists: Grandmother neurons

Electrical recordings are an extremely sparse sample of the vast number of neurons in a human brain (or even rodent brain). Perhaps the following paper will help illustrate the level of caution we should exercise in interpreting the roles of particular recorded neurons:

https://doi.org/10.1371/journal.pcbi.1005268<https://urldefense.com/v3/__https:/doi.org/10.1371/journal.pcbi.1005268__;!!IKRxdwAv5BmarQ!Zj7aotyhoDkFdDrww9wsD967R0kDbKTRMcQc1ik-bqde5ELbAchRzLF3HYMStO7wp5jdSMrIyBrHOtzUNCaGiLk$>

Just to offer my humble opinion on other topics in this thread:
* It is more likely that any given neuron is functioning as part of a larger ensemble rather than acting alone to represent some concept. That ensemble is more likely to be a dynamical system, and its "representations" are regions or attractors in the state space of the overall system.
* Another way to frame "meaning" is the actions a physical system, such as an animal, takes in the world. Neural states have meaning because they have a direct causal relationship with our body, which in turn has a causal relationship with the environment around us. Specific example: my act of emitting a certain pattern of sounds may change your behavior, which may result in me receiving some food. (Ordering dinner at a restaurant.)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.srv.cs.cmu.edu/pipermail/connectionists/attachments/20240223/d9c41d6e/attachment.html>