Increased blink rate in drug-naive acute schizophrenic patients.

Eye blinks were investigated during a standardized visuomotor task in 15 drug-naive schizophrenic inpatients (8 men and 7 women) and 15 age- and gender-matched healthy volunteers. Whereas the schizophrenics demonstrated the same precision as normal controls in executing the visuomotor task, their mean blink rate was markedly increased (16.2 +/- 10.8 versus 9.3 +/- 6.4, p less than 0.05). Following neuroleptic treatment, the blink rate decreased, and was no longer statistically distinct from controls. The changes in blink rate correlated significantly with changes in several Brief Psychiatric Rating Scale (BPRS) items: "anxiety" (tau = 0.75; p less than 0.02), "hostility" (tau = 0.78; p less than 0.02), and "unusual thought content" (tau = 0.59, p less than or equal to 0.05), but not with the neuroleptic dose given between the first and second testing. These results underscore the influence of psychopathology on blink rates in schizophrenics.