This is why pornography causes a vicious circle. When someone views pornography, he gets overstimulated by dopamine; so his brain destroys some dopamine receptors. This makes him feel depleted, so he goes back to pornography, but, having fewer dopamine receptors, this time it requires more to get the same dopamine thrill; but this causes his brain to destroy more receptors; so he feels an even greater need for pornography to stimulate him.
Krish Eswar
For more, see Harvard Scientist Explains What Porn Does To Your Brain. For more quotes, click here.
