Re: Sensory modalities and the possibility of semi-arbitrary additions

From: James MacAulay (
Date: Wed Nov 02 2005 - 22:33:34 MST

On 2-Nov-05, at 9:16 PM, Chris Capel wrote:
> On 11/2/05, Phil Goetz <> wrote:
>> HOWEVER. The problem that people rarely point out when talking about
>> adding new senses is that cortical real estate is expensive. You
>> can't
>> add a new sense without giving up something of equal value - either
>> giving up another sense, or reducing the range or resolution of that
>> sense.

And yet, in a situation where half of an infant's brain needs to be
surgically removed for some reason, that individual can (sometimes)
grow up to be a college graduate. If it happens at an early enough
age, then it doesn't completely undermine the process of development:
synaptic growth and pruning can continue even with one hemisphere.
(Cortical real estate certainly is expensive; I'm just pointing out
that it isn't always a matter of volume or surface area.)

As for the actual numbers of neurons and synaptic connections that
these exceptional people carry in their heads, I have no idea how
they compare to the rest of us. Same goes for how much energy it
takes them to run only a half-sized brain.

> The same thing occurred to me as I was pondering on this post. On the
> other hand, if the cortex truly is that generic, it should (hehe) be
> possible to extend the cortex with artificial enhancements, in a way
> similar to a computer memory upgrade. That's an interesting
> possibility.

Definitely. Until we're at the stage of mind uploads, though (or
fantastically powerful nanotech and godlike knowledge of the brain--
possibly necessary for uploads anyway), I think that any such
upgrades would have to come very early in life, before an
individual's forest of synapses has been pruned down very much (i.e.
while plasticity is still at a peak).

James MacAulay

This archive was generated by hypermail 2.1.5 : Wed Jul 17 2013 - 04:00:53 MDT