Obsessive compulsive disorder is a serious psychiatric illness that affects millions of people worldwide. People with this disease struggle with intrusive thoughts and sometimes it leads to repetitive compulsive behaviour. For example, sometimes a patient might be inclined to count the lamp posts or shops on his way and if they suspect they have missed one, they go back and start the procedure all over again.
thepsychmind: Fun Psychology facts here!
Serotonin, dopamine, acetylcholine - neurotransmitters that are responsible for happiness, love, and learning