Deferred imitation of action sequences in developmental amnesia. Paper presented at the Cognitive Neuroscience Society

& The aims of this study were to investigate whether patients with developmental amnesia (DA) associated with bilateral hippocampal volume reduction show an impairment in in-cidental nonverbal recall of action sequences, and whether the severity of this memory impairment is influenced by the se-quence structure (causal vs. arbitrary). Like adult-onset cases of amnesia (McDonough, Mandler, McKee, & Squire, 1995), pa-tients with DA did not differ significantly from their age-, sex-, and IQ-matched controls in spontaneous production of the sequences prior to modeling but recalled fewer target actions and action pairs than the control group after a 24-hour delay, independent of sequence structure. Unlike the patients with adult-onset amnesia, however, the patients with DA showed some memory for both types of sequences after a 24-hour de-lay. This difference in severity of memory impairment might reflect differences in extent of pathology and/or age at injury. &amp