Spatial and color working memory in patients with lateral prefrontal cortex lesions

Lateral prefrontal cortex (LPFC) has previously been associated with both attention and working memory. To study both of these mechanisms, patients with LPFC lesions and age-matched controls were tested on working memory tasks that included an interference condition. On a spatial working memory task, patients were impaired overall relative to controls in both no-interference and interference conditions. There was also a significant correlation between patients’ performance and the extent of damage to Area 46. Participants were also tested on a color working memory paradigm, in which they had to remember an object’s color, rather than location. LPFC patients were disproportionately impaired in the interference condition of this experiment—namely, when they had to perform an interference task during the delay period of the color working memory task. These results are discussed with respect to previous animal and human studies of attention and working memory.