RETROGRADE-AMNESIA AFTER TRAUMATIC INJURY OF THE FRONTOTEMPORAL CORTEX

An industrial manager had severe retrograde and variable but usually m ild anterograde amnesia four years after a head injury. MRI showed dam age of both temporal poles and the lateral portion of the -right prefr ontal cortex. The prefrontal and temporal cortical damage on the right side extended deeply into the white matter while the temporal cortica l damage on the left side was much smaller. There was an additional le ft temporo-parietal lesion. The patient was of average intelligence. H is attention, short term memory and learning ability were average or s omewhat below average. His old memories were severely affected for the personal-episodic domain and less so for semantic remote memory abili ties. Therefore an anatomical dissociation between anterograde and ret rograde amnesia is possible at the anterior temporal regions, possibly interacting with the prefrontal cortex; these regions seem necessary for the retrieval of old episodic memories.