Punding

Punding is human activity characterized by compulsive fascination with and performance of repetitive, mechanical tasks, such as assembling and disassembling, collecting, or sorting household objects. For example, punding may consist of activities such as:
 * collecting pebbles and lining them up as perfectly as possible,
 * disassembling doorknobs and putting them back together again,

People engaging in punding find immersion in such activities comforting, even when it serves no purpose, and generally find it very frustrating to be diverted from them.

Punding is the result of dopamine overactivity. It is commonly associated with side effects of drugs used against Parkinson's disease and with the use of methamphetamine (in which context it is known as tweaking), which increases dopamine release and blocks its uptake. In Parkinson's Disease it can be cured by lowering the medication dose, or adding (atypical) antipsychotics, which act by counteracting the effect of dopamine.

Punding is also similar to behaviors associated with autism.