A meta-analysis of indirect memory tests for novel material in organic amnesics.

A meta-analysis was conducted on studies of implicit memory for novel and familiar information in organic amnesic patients and healthy controls. Across studies, the amnesics performed equivalently to the controls on indirect memory tests for familiar information. However, the controls performed better than amnesics for indirect memory tests for novel item and novel associative information. This is in accord with memory theories which suggest that medial temporal lobe structures are essential for encoding and storing arbitrary associations between items or events.