Saccadic hypometria in drug-naive and drug-treated schizophrenic patients:A working memory deficit?

In certain conditions patients with schizophrenia make markedly smaller (hy pometric) saccades than controls. This hypometria has been thought to refle ct dopaminergic blockade as a result of antipsychotic medication. We tested this hypothesis by comparing the performance of an antipsychotic-naive gro up and an antipsychotic-treated group of first-episode schizophrenic patien ts on a predictive saccade paradigm. We explored the possibility that hypom etria reflects a spatial working memory deficit by correlating performance on neuropsychological tests of mnemonic function with saccadic accuracy. Bo th the drug-naive and treated schizophrenic patients made hypometric saccad es when compared with a group of matched controls. Primary saccade amplitud e also correlated significantly with performance on some of the neuropsycho logical tests. These results are discussed in terms of the roles of cortica l dopamine and working memory deficits in schizophrenic patients.