This term involves maladaptive behaviour that impairs the individuals ability to perform normal daily functions. Such maladaptive behaviours prevent the individual from living a normal, healthy lifestyle.
Dysfunctional behaviour is not always caused by a disorder it may be voluntary. These dysfunctions include depression, dementia, psychosis, sleep disorders arising from Parkinson′s and Huntington′s disease, Tourette′s syndrome, as well as multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration.