well suck me sideways, we've got a smart kid on our hands! this is overwhelmingly true. the abundance and spontaneous levels of hormones certainly effect neurotransmission and reuptake. while on, neurophysiological activity sky rockets, not only upon euphoric neurotransmitters, but depressive NT's as well. when we come off, we maintain a neurological need for euphoric NT abundance/activity/reuptake without the proper means to accommodate. much like a smoker quitting, suppressing natural nicotine levels then abruptly stopping synthetic intake of nicotine, leaving their brains with an absolute lack of nicotine, natural or synthetic.
We create a dependency of sorts upon this neurotransmitter activity and then withdraw the means of satisfying the need we have created through hindering natural suppression. You combine this neurological withdrawal with the aforementioned social/behavioral tendencies...you've got a powerful recipe for depression.
Personally, I am a firm believer in behavior and perception as an influence on neurological activity. We displace our views/expectancy/dependency of euphoria, we induce a neurological response. Meaning, as I mentioned, I have conditioned myself to not reach such a euphoria while on, minimizing a spike neurotransmitter activity, minimizing the withdrawal of NT activity when coming off...all perceptually and behaviorally. it is an entire package that one must be aware of to decrease or avoid post cycle depression. and it takes a certain level of neurological, psychological, behavioral, and perceptual understanding to refrain from undergoing such depression.
fantastic input tommy, reps.