I sit between two coworkers, we are software enginners and we share the same table. The guy on my left spends all his day knocking on his part of the table (like it were drums), whistling, doing some hand gestures in the air, doing skin picking and other minors annoying habits. It's extremely distracting and annoying. I can't concentrate on my work since this began.
The others coworkers aren't as bothered as I am, probably because they are at certain distance, so at first I thought it was my problem, for becoming bothered with something so simple as gestures, whistles and table knockings.
Someday he told us he visits a psychologist every week, so we imagine he maybe have a kind of depression or like, so it's complicated to just ask him to stop doing those things, this would be the last resource.