PATHOLOGICAL LAUGHTER - COMMON VS. UNUSUAL ETIOLOGY AND PRESENTATION

Pathological laughter and crying is a well known clinical phenomenon w hich in most cases appears in association with diverse neurological an d psychiatric symptoms and signs. It is not a disturbance of affectivi ty but rather of the motor concomitant of affective expression. Its ma in clinical characteristics are: absence of voluntary control and abse nce of the: corresponding change in mood It is not accompanied by the emotional lability of the organic brain syndromes, it does not present the inappropriate jocularity of the patients with frontal lobe distur bance, it is not due to the intoxicating effect of alcohol or addictiv e drugs and there are no typical symptoms of manic syndromes (such as grandiose self-esteem, flight of ideas, hyperactivity, etc.). In this paper three cases of pathological laughter are presented, two of these associated with organic brain conditions. The discussion will deal in particular with aetiological considerations and psychopatholoy of the third case which was unusual because it was a monosymptomatic conditi on and seemed to be the expression of a posttraumatic stress disorder.