Diet, water, and sex are all-natural responses for the brain. The brain responds to a satisfying meal or a satisfying sexual experience by producing dopamine, a neurotransmitter. Dopamine helps us remember things. When dopamine is released, the body knows when and how it happened, allowing the feeling of the pleasurable experience to be repeated. The issue with porn is that it can abuse this natural pleasure. To get the desired level of dopamine, people may need to watch pornography more frequently, for longer periods of time, or with more controversial content. Addictions and other repetitive activities are examples of this. The brain adapts to the effects of alcohol by drinking more or more strong alcohol to get the same results. Reduced dopamine activity in the brain may affect symptoms of depression and anxiety.