FROM SUPERSTITIOUS BEHAVIOR TO DELUSIONAL THINKING - THE ROLE OF THE HIPPOCAMPUS IN MISATTRIBUTIONS OF CAUSALITY

Nearly half a century ago B.F. Skinner proposed the hypothesis that hu man superstitiousness would be equivalent to the 'superstitious' behav ior displayed by animals in operant situations involving response-inde pendent reinforcement. Surprisingly, no attempt has ever been made to test this equivalence hypothesis experimentally. In the light of recen t evidence for a common neurological basis of both superstitious belie fs held by normal subjects and delusional ideas of psychotic patients, Skinner's hypothesis has become topical again. We present an extensio n of the hypothesis which assumes dysfunction of the medial temporal l obe, in particular of the hippocampus, to be responsible for condition ed superstitions in animals, for common everyday superstitions, and fo r schizophrenic delusions. This hypothesis is based on (1) the observa tion of an enhanced 'superstitious' reactivity in hippocampectomized a nimals, (2) findings of an increased occurrence of popular superstitio ns in patients with a temporal-limbic epileptic focus, and (3) morphol ogical and pharmacological evidence for schizophrenic delusions to be causally related to hippocampal damage.