This is most important: What determines the contribution of a given brain unit to the operation of the system to which it belongs is not just the structure of the unit but also its place in the system.
The whereabouts of a unit is of paramount importance. ...On numerous occasions I will refer to the presumed function of given brain regions, but such references should be taken in the context of the systems to which those regions belong. I am not falling into the phrenological trap. To put it simply: The mind results from the operation of each of the separate components, and from the concerted operation of the multiple systems constituted by those separate components.引自 POSTSCRIPTUM
(p15)
When it comes to explaining behavior and mind, it is not enough to mention neurochemistry. We must know whereabouts the chemistry is, in the system presumed to cause a given behavior. Without knowing the cortical regions or nuclei where the chemical acts within the system, we have no chance of ever understanding how it modifies the system's performance (and keep in mind that such understanding is only the first step, prior to the eventual elucidation of how more fine-grained circuits operate). Moreover, the neural explanation only begins to be useful when it addresses the results of the operation of a given system on yet another system. The important finding described above should not be demeaned by superficial statements to the effect that serotonin alone "causes" adaptive social behavior and its lack "causes" aggression.引自 POSTSCRIPTUM
(p77)
It is important to realize, however, that knowing that a given chemical (manufactured inside or outside the body) causes a given feeling to occur is not the same as knowing the mechanism for how this result is achieved. Knowing that a substance is working on certain systems, in certain circuits and receptors, and in certain neurons, does not explain why you feel happy or sad. It establishes a working relationship among the substance, the systems, the circuits, the receptors, the neurons, and the feeling, but it does not tell you haw you get from one to the other. It is only the beginning of an explanation. If feeling happy or sad corresponds in good part to a change in the neural representation of ongoing body states, then the explanation requires that the chemicals act on the sources of those neural representations, that is, the body proper itself, and the many levels of neural circuitry whose activity patterns represent the body. Of necessity, understanding the neurobiology of feeling requires the understanding of the latter. If feeling happy or sad also corresponds in part to the cognitive modes under which your thoughts are operating' then the explanation also requires that the chemical acts on the circuits which generate and manipulate images. Which means that reducing depression to a statement about the availability of serotonin or norepinephrine in general—a popular statement in the days and age of Prozac—is unacceptably rude.引自 POSTSCRIPTUM
To a first approximation, the elementary secrets of mind reside with the interaction of firing patterns generated by many neuron circuits, locally and globally, moment by moment, within the brain of a living organism.引自 POSTSCRIPTUM
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