Anhedonia, alexithymia and locus of control in unipolar major depressive disorders

The relationship between anhedonia, alexithymia and locus of control was studied in a group of healthy subjects (n = 56) and in a group of unipolar major depressives (n = 59). These dimensions were rated using the Physical Anhedonia Scale (PAS), the Toronto Alexithymia Scale (TAS) and the Internal Powerful others and Chance Scale. The unipolar major depressives were divided into two subgroups using the endogenomorphic subscale of the Hamilton Depression Rating Scale. There are respectively 25 and 17 depressives in the nonendogenomorphic (NENDO) and endogenomorphic (ENDO) subgroups. The unipolar major depressives were significantly more anhedonic, alexithymic and externalized than the controls. In the ENDO group the PAS and TAS Feelings scores were positively correlated suggesting that a third variable of emotional deficit could characterize endogenomorphic depression. In the NENDO group the PAS, TAS Daydreaming, Powerful others and Chance scores were positively correlated. In nonendogenomorphic depression anhedonia could be related to a poverty of imagery and could be interpreted as a consequence of external causes.