[The French concept of "Athymhormie" (Loss of vital force) from 1922 to the present].
The psychiatric concept of athymhormie (loss of vital force "élan vital" and affectivity) was developed at the beginning of the 20th century and used exclusively in France, until it was fortunately adopted by mostly French-speaking neurologists. The authors of the concept, M Dide and P Guiraud, considered the term an independent entity, an heir to dementia praecox, for which they did not like to substitute a "schizophrenia" with blurry boundaries. This term then came to mean to them, and to most French psychiatrists to this day, the basic core of psychosis' deficient forms. The word athymhormie (or loss of psychic self-activation) is now also used in neurology for the behavioural and emotional consequences of lesions caused on basal nuclei and, more widely, of a circuit associated with the limbic loop. However, the phenomenological reality of the associated disorders and the relevance of the same name can be questioned. This review concludes that although the settings--in a psychiatric or a neurologic clinic--where athymhormie takes place are very different, the choice of the same name is justified in a renewed and symptomatic neuropsychiatric approach. The objective of this approach is to explore why some symptoms, common or similar, could represent the lack of a physiological function, presumed here to be motivation.