Future and previous goals represented by different neuronal population the prefrontal cortex.

Genovesio et al have measured the activities of a large number of individual prefrontal cortical neurons as monkeys selected a future goal on the basis of events from a previous trial involving visual cues. They found that prefrontal neurons had activity that reflected either previous goals or future goals, but only rarely did individual cells reflect both. Their comment: "This finding suggests that essentially separate neural networks encode these two aspects of spatial information processing. A failure to distinguish previous and future goals could lead to two kinds of maladaptive behavior. First, wrongly representing an accomplished goal as still pending could cause perseveration or compulsive checking, two disorders commonly attributed to dysfunction of the prefrontal cortex. Second, mistaking a pending goal as already accomplished could cause the failures of omission that occur commonly in dementia."