CATAPLEXY, a symptom of narcolepsy, is an illuminating example of paralysis of voluntary movement induced by emotion. In all the domain of psychosomatic medicine cataplexy is almost without a peer as a compelling illustration of how emotion can give rise, immediately and dramatically, to a physical symptom.In most of psychosomatic medicine we deal with chronic situations: A man hates his boss and reacts with a peptic ulcer. Cataplexy, in contrast, provides a chance to study acute reactions. Thus, a man may be stricken with paralysis at the moment he raises his hand in anger against his child.In fully developed narcolepsy there are sleep attacks and paralytic attacks. The latter occur oftenest on emotion and are then called cataplexy. The most striking occurrence is on laughter. On laughing heartily, the patient will collapse in a heap, conscious but unable to move or speak, and will lie helpless for some