The grandmother cell is a theoretical cell, somewhere in the visual
system of the brain, that would respond only to your grandmother.
The idea rests on the fact that the visual system works by building up
simple shapes into complex images. Early in the visual system (i.e.
close to the eye) you have neurons that will respond only to lines in
certain directions, the ends on lines etc.. and only in certain parts
of visual space. As you move further along the visual system (i.e. the
visual cortex, into the temporal cortices) neurons begin to respond to
more complex shapes, i.e. faces, but now in any part of visual space.
See this figure here:
This cell in the temporal cortex of a monkey responds to a monkeys
face, but only when the face is largely side on.
>From these kind of experiments, (I believe) people hypothesized that
there would a single neuron that would respond to your grandmother, and
only to your grandmother. This idea (I believe) was used to redicule
the theory (just like Schrodingers cat was used). But as far as I am
aware, the theory generally goes that there would a) be more than 1
cell that would respond to your grandmother (probably an array of
them), but that that same neuron (in combination with other neurons)
would respond to a different, but similar visual input.
I'm not so sure about that last bit; maybe someone can correct me.
ccm at crescentcitymedia.com wrote:
> Would love to understand more about the "Grandmother Cell" theory. Is
> this the same thing as "genetic knowledge?"
>> Also is anyone aware of human neuroscientific research being carried out
> in countries where there is little or no monitoring of
> ethical/professional behavior? What is the impact of biotech and
> nanotech in these countries?
>> Thanks in advance for your response. I am a journalist and a member of
> the media.
>>>> > -------- Original Message --------
> > Subject: [Neuroscience] Grandmother Cell Theory
> > From: "simple_one" <davidglt7 at yahoo.com>
> > Date: Sun, August 20, 2006 5:26 am
> > To: neur-sci at magpie.bio.indiana.edu> >
> > Hello everyone,
> > I appreciate if someone can point me in the right direction and write
> > down for me some book or article references that invalidate the
> > grandmother/gnostic cells theory.
> > I ran a search on PubMed and the only new relevant article that came up
> > was the "Genealogy of the Grandmother Cell" by Charles G Gross.
> > I have a background in computer science and I have been studying
> > neuroscience by myself for a couple of years now.
> > Unfortunately some of the arguments presented in there in favor of
> > having a piece of information represented as an ensemble of cells seem
> > to me that they actually give credit to the gnostic cell theory. Like
> > this argument: "Even the most selective face cells usually also
> > discharge, if more weakly, to a variety of individual faces".
> > Most of the other books and articles I have read don't deal with this
> > theory at all so I assume that perhaps it was invalidated some time
> > ago.
> > Thanks in advance.
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