Focal retrograde amnesia and the attribution of causality: An exceptionally benign commentary.

Kopelman offers an invaluable and comprehensive review of empirical and theoretical issues relating to focal retrograde amnesia and related conditions. He makes two main points: (1) That many of the published cases of focal retrograde amnesia in fact showed significant anterograde memory impairment, and thus should strictly not be classified as cases of focal retrograde amnesia; (2) that there are hazards in attributing causality in patients with retrograde amnesia, especially those with a major autobiographical component. In the case of his first point, I suggest that his observations are a matter of interpretation, essentially revolving around the defining criteria for the selection of memories to be compared and for regarding one set of memories as "disproportionately impaired" compared to the other. With regard to the second point, however, I largely concur with his observations, adding some reservations of my own. I conclude that although some patients with focal retrograde amnesia may represent a diagnostic dilemma when it comes to attributing causality, those who are shown to have a clear neural basis to their memory loss provide an avenue for exploring the brain's plasticity in accommodating the formation of new memories despite the loss of equivalent old memories.