Pupillary abnormalities in schizophrenic patients during long-term administration of psychotropic drugs: dissociation between light and near vision reactions.

Pupillographic studies were made of the reactions to light and near vision in 12 schizophrenic patients under long-term administration of psychotropic drugs. The results showed a significant reduction in the light reaction, while the near vision reaction was preserved. The pupillographic study revealed not only reduction in amplitude of the light reaction but also changes in dynamic aspects of the reaction, i.e., prolonged latency time, shortened constriction time, and half redilatation time after the light stimulus. The mechanisms underlying the dissociation between light reaction and near vision reaction induced by long-term administration of psychotropic drugs are obscure, but both the peripheral and central actions of these drugs may be involved.