Comments interpolated (v. infra)
In <lxww1773mh.fsf at lci.isr.ist.utl.pt> yoda at isr.ist.utl.pt ("Rodrigo
>>> Hi. I'm a researcher in the field of AI (artif. intelligence),
>my work is about artificial emotions (or emotion-based agents, if you
>prefer the name), but I am extremely interested in neuroscience. In
>our AI discussion group we have been debating the following issue, but
>we are kind-of stuck... Here is my question to this forum:
>> Let's assume a functional division of the CNS in three layers
>[MacLean]: a "reptile" brain which is based in reactive behavior, a
>"mamalian" brain which involves emotions (limbic system), and the
>neocortex associated with reasoning, etc. The question is: how can the
>reactive layer (e.g., the spinal cord response to a burning stimulus)
>and emotions (e.g., fear) be functionally distinguished. I mean, how
>can one describe these two layers without resorting to morpholigic
>arguments (such as this involves the thalamus, or that involves just
>the spinal cord)?
To begin with, if you are modeling based on a cartoon
(tripartite brain), you're "not playing with a full deck".
ALL parts of the human brain have evolved, and the evolution
includes intricate interrelationships among all parts. (no
disrespect to MacLean, who was one of my speakers at a NYNG
conference I organized many years ago).
You cannot describe "layers" without reference to anatomy,
inasmuch as "layers" itself seems to be an anatomical concept
(default case: metaphorical concept).
How do you "functionally" differentiate? Define your terms.
If you mean "reflex withdrawal", this can be done at a spinal
level. If you mean "increased heart rate, other autonomic
activity", you are involving higher levels.
Within the amygdala, there are "switching" points which
transmit activating stimuli via separate paths for motor or
autonomic responses, so here is one basis for differentiating.
All presupposing you have a definition of "emotion"... I have
referred to components of what some people would say are
necessary (but not sufficient) aspects of emotional experience.
>> Another question that is related with this is: when did the
>limbic system appeared, in the species evolutio, in the brain
>(reptile? mamalian? birds? ants? bees? spiders?)? And more
>imposrtanty, what was the _qualitatively_ step that evolution took
>when emotions appeared? What was the shortcomings of the non-emotional
>animals that lead to the appearence of emotions?
First, define "emotions". After that, we can talk.
F. Frank LeFever, Ph.D.
New York Neuropsychology Group
> I'd appreciate any response/discussion around these questions,
>either by email or in this newsgroup.
>>*** Rodrigo Martins de Matos Ventura, alias <Yoda>
>*** yoda at isr.ist.utl.pt, http://www.isr.ist.utl.pt/~yoda>*** Teaching Assistant and MSc. Student at ISR:
>*** Instituto de Sistemas e Robotica, Polo de Lisboa
>*** Instituto Superior Tecnico, Lisboa, Portugal
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