Abstract
The state-of-the art knowledge aboutprevalence, pathogenesis and treatment of depressivesyndromes associated with sclerosis multiplex,Parkinson's disease and Huntington's chorea is outlinedin the paper. In the authors' opinion this typeof research provides an exceptional opportunity tostudy the relationship between structural changes inthe central nervous system and changes in psychologicaljunctions, thus contributing to the development of an interdisciplinary science termed "neuropsychiatry" by some.