Remembering and knowing in patients with frontal lobe injuries.

Two experiments compared the performance of patients with pathology restricted to the prefrontal cortex to healthy controls on recognition tests that were followed by the remember/know procedure. Across both experiments, patients recognized roughly as many target items as control participants. Injuries centered in the frontal poles resulted in deficits that were selective to episodic remembering while apparently sparing semantic knowing. Patients with lesions restricted to dorsolateral prefrontal cortex were not impaired at either remembering or knowing. Results demonstrate a dissociation of cognitive function within the prefrontal cortex, and suggest that episodic remembering may share a family resemblance with other neurocognitive functions dependent upon polar aspects of the frontal lobes, such as self-recognition, anticipation, and planning.