Connectionists: Real or virtual? Grandmother cells or "virtual" grandmother patterns?

[Richard Loosemore]

Back in 2010 I wrote a paper with T.A. Harley in which we argued that
"concepts" (like [grandmother]) are likely to be *virtual* patterns of
activity on neural circuits and NOT hard coded into the circuits themselves.

So, for example, a virtual pattern of activity might come and go between
active and dormant states, or it could move around the brain (perhaps
from one column to another).

In support of this conclusion, we pointed out that  common
interpretations of brain imaging data were simply not consistent with
the usual assumption, which is that neurons directly represented
concepts.  We pointed, in particular, to the infamous Jennifer Aniston
Cell paper, where the virtual concept hypothesis was the only viable one.

And yet, the "virtual" idea is almost completely absent from the
literature.  Why?  If concepts are virtual, this would make a nonsense
of many interpretations of neuroscience results, because firing patterns
would only have a weak relationship to meaningful entities like
concepts.  (Think about it:  if concepts can wander around the cortex,
what is the point in saying that a particular place in cortex
corresponds to a semantically tangible thing?).

Anyway, I note that a recent paper from Laura N. Driscoll, Noah L.
Pettit, Matthias Minderer, Selmaan N. Chettih, and Christopher D. Harvey
(Dynamic Reorganization of Neuronal Activity Patterns in Parietal
Cortex): Dynamic Reorganization of Neuronal Activity Patterns in
Parietal Cortex

http://www.cell.com/cell/pdf/S0092-8674(17)30828-0.pdf

(Overview here:
http://news.harvard.edu/gazette/story/2017/08/brain-flexibility-changes-the-way-we-remember-and-learn/)

... brings yet another confirmation of the "virtual" concept
hypothesis.  The most parsimonious interpretation of their results is
that the activity patterns are changing precisely because the "concepts"
(when active) are not identifable with fixed hardware, but are actually
virtual.

It seems to me this is one of the most important issues in all of
neuroscience, since it changes the flavour of every result out there.

What do you think?

---

Richard Loosemore



Reference

Loosemore, R.P.W. & Harley, T.A. (2010). Brains and Minds: On the
Usefulness of Localization Data to Cognitive Psychology. In M. Bunzl &
S.J. Hanson (Eds.), Foundational Issues in Human Brain
Mapping.Cambridge, MA: MIT Press

https://www.academia.edu/563588/Brains_and_Minds_On_the_Usefulness_of_Localization_Data_to_Cognitive_Psychology

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