PHARMACOLOGICAL RELATIONSHIP OF ANTISACCADE AND DYSKINESIA IN SCHIZOPHRENIC-PATIENTS

Abnormalities in saccadic eye movements have been found in schizophren ics with tardive dyskinesia (TD). This finding supports accumulating e vidence for a GABAergic dysfunction in the subcortical-cortical circui ts controlling motor and oculomotor behavior. We found that in respons e to muscimol, a direct-acting GABA agonist, changes in the antisaccad e error rate and dyskinesia score were strongly correlated. We then lo oked at the relationship between these measures during single-blind ha loperidol withdrawal. Significant changes occurred in antisaccade erro r during drug withdrawal, but the final measure was not significantly different from the baseline assessment. Antisaccade error change score s were not correlated with dyskinesia change scores. Change score in a ntisaccade error was positively correlated with change on the Brief Ps ychiatric Rating Scale, specifically with the Anxiety/Depression facto r. These findings suggest that GABAergic mechanisms are more robust th an dopaminergic mechanisms in the pathophysiology of persistent tardiv e dyskinesia.