Re: Evolution, aggression, and men: Hormones matter?

Sun, 23 Jul 95 16:10:09 EDT

In article <> (Greg Stevens) writes:

>> (Greg Stevens) writes:
>>>In <3uh7b7$> (Bryant) writes:
>>>>Greg Stevens <> wrote:
>>>>>irritability. But here cause and effect is interestingly tangled.
>>>>>If increasing testosterone has the effect of inhibiting noradrenergic
>>>>>activity, and dominance increases testosterone, then it could be that
>>>>>rather than the perspective "noradrenergic activity leads to aggression"
>>>>>it may be more informative to say "noradrenergic activity leads to
>>>>>the desire to be calmed, and one channel for this is via dominance leading
>>>>>to testosterone-induced inhibition of noradrenergic activity."
>>>>If dominance is a given once obtained, this makes sense. If, however,
>>>>dominance is challenged often, achieving it is not a good technique of
>>>>soothing one's nerves.
>>>Well, societies develop into established status-heirarchies, and in
>>>primates of all kinds (humans included) status seems to be correlated
>>>with both inversely to some degree with noradrenergic activity and
>>>directly to some degree with testosterone. It can be hypothesized that
>>>the stability of such heirarchies would be reinforced through feedback --
>>>successful dominance -> testosterone increase -> noradrenergic decrease ->
>>>calm & confidence -> higher probability of successful dominance.
>>>This, plus social reinforcers of status. Thus, in a somewhat stable
>>>heirarchy, an individual may be observed to "pick on" members of lower
>>>status while NOT using this mechanism against members of higher status.
>>>This preferencial-picking-on has been observed.
>>The behavioral pharmacology of the above is a bit oversimplified;
>>however, as an addendum...decreases in the neurotransmitter in the
>>brain lead to depression and an upregulation of the noadrenergic
>>receptors in most systems I'm familiar with. So I would not equate
>>calm with depression by the above scheme. It is interesting to
>>speculate on whether the "top dog" once it has attained this status
>>becomes depressed: no more fighting to get to the top, only fighting
>>to stay there?
>I recognize that my description of the behavioral pharmacology is simplified,
>but I do the best I can between 1) my understanding and 2) having a
>conversation about it on the internet. :-)
>I am intrigued by what you say above, and want to make sure I understand
>what you are saying. In my understanding, depression is usually correlated
>with HIGH levels of cortisol and norepinephrine, where the receptors have
>upregulated to a higher resting level of NE and therefore have lowered
>dynamic responsivity. BUT, I know that my info on this comes mainly from
>trauma literature, so this may not be true of "depression in general."
>Do you know anything about this distinction? My understanding, based on
>the trauma literature, was that one way to physiologically differentiate
>"depression" and "calm" was that "calm" is lowered noradrenergic activity
>and autonomic nervous system activity, while "depression" is high noradren-
>ergic activity which has been adapted to, rsulting in abnormally low
>autonomic nervous system activity. I was under the impression that this
>is what led Panksepp to classify depression as a kind of hyperarousal.
>Greg Stevens
The cause of depression is not known. I'm not familiar with Panksepp.
Anyway, my addendum was also simplified. What happens is that there is
a depletion of available norepinephrine (NE) at the synapse. This
depletion leads to an up-regulation of pre- and post-synaptic NE re-
ceptors. The system now has increased sensitivity to NE, but it is
not available in sufficent concentrations. Pharmacological treatment
usually has involved the use of NE-reuptake blocking drugs. These drugs
increase the NE levels in the synapse and eventually result in a down-
regulation of the NE receptors. The physiological effects of the drugs
I have described are "immediate" in that it can occur in a few hours.
Paradoxically, the behavioral outcome;i.e., the end of the feeling of
depression, takes anywhere from 2-6 weeks. This indicates that the treatment
and the physiology do not adequitely describe what is depression. It
is rather(!) more complex and the subject of intense study.
Your description of calm seems correct in that there is a decrease
in the fight-or-flight response. Following long periods of arousal and
activation of the hypothalamo-pituitary-adrenal axis, there can result
a physiological depression which could accompany the calm you describe.
I would recommend reading the works on Stress by Hans Selye.

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