►Everything we do is for dopamine -- see: the 2017 Nobel Prize awarded for tracing the path of dopamine through the brain.
►When we "O.D." on this pleasure chemical, the receptor shut down in order to preserve the incentivising effects it was evolved to carry.
►The opposite to dopamine overdosing, is depression -- eventually, suicide.
►When dopamine receptors shut down, we need more dopamine to feel as we did with less -- see example: tolerance-building drugs and escalating drug use; extreme sportspeople; returning service people.
►If people (mainly males) are watching excessive porn -- notionally, consistently more than once every couple of days -- their brains will become inured to that kind of stimuli; thereby, requiring more and more, and more extreme titillation to elicit the same feeling as what they had in the past.
►If someone is indulging in pornographic voyeurism on very regular basis (multiple times per diem), than they are likely going to suffering from the effects of dulled dopamine receptors -- requiring them seek out more potent "hits" each time, to continue receiving the same of better "highs".
►Case in point: Faggots are synonymous for using meth (et al.) to heighten the pleasure of their faggotry (vernacular: "poppers") -- they will get high, so as to gape their sphincters wider (for "fisting"; inserting inordinately large objects into their rectums, etc.), or to remain erect even into the post-orgasm "refractory period":
>https://www.imdb.com/title/tt9001652/>https://putlocker.unblockit.ch/watch/OGgYknav-crystal-city.html 