Errors of memory-guided saccades in humans with lesions of the frontal eyefield and the dorsolateral prefrontal cortex

Behavioral studies in monkeys and humans suggest that systematic and variab le errors of memory-guided saccades reflect distinct neuronal computations in primate spatial memory. We recorded memory-guided saccades with a 2-s de lay in three patients with unilateral ischemic lesions of the frontal eye f ield and in three patients with unilateral ischemic lesions of the frontal eye field and the dorsolateral prefrontal cortex. Results suggest that syst ematic errors of memory-guided saccades originate in the frontal eye field and variable errors in the dorsolateral prefrontal cortex. These data are t he first human lesion data to support the hypothesis that these regions pro vide functionally distinct contributions to spatial short-term memory.