SPONTANEOUS DYSKINESIA IN SUBJECTS WITH SCHIZOPHRENIA SPECTRUM PERSONALITY

Objective: The study of spontaneous dyskinesia in schizophrenia is con founded by the widespread use of neuroleptics. The authors hypothesize d that spontaneous dyskinesia would be present in subjects with schizo phrenia spectrum personality (schizoid, paranoid, or schizotypal). The y also tested the hypothesis that dyskinetic-like movements would incr ease after repented dextroamphetamine challenge to the dopaminergic sy stem. Method: Dyskinetic-like movements were assessed in 34 spectrum s ubjects and 22 normal subjects; nine subjects from each group were adm inistered both placebo and repeated dextroamphetamine challenges. Resu lts: Spectrum subjects had more dyskinetic-like movements than normal subjects. Spontaneous dyskinesia was present in 12% of the spectrum su bjects but was not seen in the normal subjects. Subjects with schizoty pal Personality had more dyskinetic-like movements than subjects with schizoid personality or normal subjects. Dyskinesia was present in 24% of the schizotypal subjects but not in the other groups. Dyskinetic m ovement scores correlated with positive symptom scores. With repeated amphetamine challenge, normal subjects showed a pattern of behavioral sensitization (an increase in dyskinetic-like movements), but spectrum subjects showed an abnormal response (fewer dyskinetic-like movements ). Conclusions: Dyskinesia and dyskinetic-like movements are more comm on in subjects with schizophrenia spectrum personality (primarily schi zotypal) than in normal subjects and are related to positive symptoms. A failure of normal behavioral sensitization mechanisms after dextroa mphetamine challenge is seen in subjects with schizophrenia spectrum p ersonality.