Grandmother Cells?

Does a single neuron code for Bart Simpson's face? Mind Hacks reports on an article in Nature suggesting some evidence for 'grandmother cells.'

This week's edition of the science journal Nature reports that single brain cells may be specialised for recognising specific faces.

This is an interesting finding, as it provides support for a derided hypothesis known as the 'grandmother cell' theory, that was thought up to ridicule attempts to reduce human experience down to smaller and smaller components of the brain.

Neuroscience often develops by trying to understanding how smaller parts of the brain support larger processes. Bologist Jerry Lettvin argued that we can't expect everything to reduce down to the smallest level, as some things will be distributed across the brain.

It is unlikely, he argued, that there is a single brain cell to represent each person we know, a neuron that is active when we see our grandmother, for example.

This has since been used as an argument against any theory that is seen as over-simplifying how things are represented in the brain.

But now, a team led by neuroscientist Rodrigo Quian Quiroga has identified neurons which do seem to be active for individual faces.

He implanted harmless electrodes into the temporal lobes of volunteers undergoing surgery for epilepsy.

Quiroga then showed the participants pictures of famous faces, and discovered some cells were only active for individual faces in the set - Halle Berry, or even members of The Simpsons.

Of course, it's impossible to say whether these cells are truly selective for an individual face out of all the ones a person may know, but this level of selectivity is a great surprise for those who thought individual cells would be active for very general features of the visual world.

Koch Discussion

We meet next Wednesday at noon in SC 200 to discuss Koch, chs 8-10.

You can watch Kock's video lectures, based on the text, at http://www.klab.caltech.edu/cns120/videos.php

Koch discussion continues

The Quest For Consciousness discuss group meets next Wednesday, June 21, at noon in SC 200. We'll discuss chs. 5-7.

Here are a number of additional online articles you might find useful:

David Chalmers, "What is a Neural Correlate of Consciousness?" in Neural Correlates of Consciousness: Empirical and Conceptual Issues, Metzinger, ed.

A. Noe and E. Thompson, "Are there Neural Correlates of Consciousness?" from Journal of Consciousness Studies

Ned Block, "How to Find the Neural Correlates of Consciousness"

Welcome to Neuroscience at NKU

Look to this web log for news, information, commentary, book reviews, and anything even remotely related to the study of neuroscience at Northern Kentucky University. Members of the blog include faculty and students interested in addressing a broad range of topics on the Mind-Brain from a variety of disciplinary perspectives.

Koch Links

Koch has a website for his book The Quest for Consciousness with some sample chapters and information about the author.

Some Crick-Koch articles:
"A Framework for Consciousness" in Nature Neuroscience 6(2):119-126, 2003.
"Consciousness and Neuroscience" in Cerebral Cortex, 8:97-107, 1998.
"The Problem of Consciousness" in Scientific American, Sept. 1992

Also, here are some links to online reviews of Koch's book.

Interview with Koch
Hameroff review
Chris Frith review
Bernard Baars review
Martinez-Conde review
Jeremy Wolfe review
Searle review in NYRB (01.13.05) [requires password]
Harnad-Searle exchange in NYRB (06.23.05)

Discussion Group Meeting

The next CNS discussion group meeting is Wednesday, June 14 at 12:00 in SC 200. We'll discuss Koch's The Quest for Consciousness, chapters 3 and 4.