Smooth pursuit latency in gap and non-gap conditions in schizophrenic subjects.

It has been demonstrated in normal subjects that smooth pursuit latency is reduced in gap pursuit tasks. We have now measured smooth pursuit latency in a group of schizophrenic subjects in both gap and non-gap conditions. In non-gap tasks pursuit latency was longer in the schizophrenic subjects than in controls. While the addition of gaps produced reductions in pursuit latency in the schizophrenic subjects, the effect was more variable than in controls, with a greater asymmetry between rightward and leftward pursuit latencies. Our results are consistent with the hypothesis that pursuit initiation is modified in schizophrenia and that as with the gap effect on saccades, the gap effect on pursuit is also modified.