8. Anhedonia
It is the inability of experiencing pleasure or joy. It is common to experience this as an extreme manica state that occurs when a person has this bipolar mood disorder. As the saying goes, ‘what goes down, must come up’. And it does. The person will not enjoy sex, family, food, work, games or anything else.
I know a person who was in a depressive episode and ended up on a rollercoaster. It was of the vertical drop type. The individual stated that the extreme gravity pulled them out of a depressive state. It was almost like a reset button. If it were up me, I would make this a top priority for future research.