Deferred Imitation of Action Sequences in Developmental Amnesia

Abstract

Abstract& The aims of this study were to investigate whether patients with developmental amnesia (DA) associated with bilateral hippocampal volume reduction show an impairment in incidental nonverbal recall of action sequences, and whether the severity of this memory impairment is influenced by the sequence structure (causal vs. arbitrary). Like adult-onset cases of amnesia (McDonough, Mandler, McKee, & Squire, 1995), patients 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 delay. This difference in severity of memory impairment might reflect differences in extent of pathology and/or age at injury. &

Exploring memory in infancy: deferred imitation and the development of declarative memory

“…Temporal lobe amnesics perform normally on procedural memory tasks, but perform poorly on declarative memory tasks (for review see Squire, 2004), suggesting that the temporal lobe is crucial to declarative memory. The finding that patients with temporal lobe amnesia or developmental amnesia associated with a reduction in hippocampal volume also have difficulty with an adultappropriate version of the deferred imitation task provides support for the idea that deferred imitation tasks are a non-verbal measure of declarative memory (McDonough et al, 1995;Adlam et al, 2005). Furthermore, the pattern of retention exhibited in the deferred imitation paradigm conforms closely to that seen in declarative memory paradigms.…”

Accounting for change in declarative memory: A cognitive neuroscience perspective

“…While controls produced more target actions spontaneously and during cued testing than during the baseline phase, amnesic patients were no more likely to use the objects to produce target actions than were inexperienced controls, who had not seen the target actions demonstrated the previous day. Patients with "developmental amnesia", who incurred hippocampal damage early in life, also exhibit impairments on the deferred imitation task, although their impairment is restricted to the recall of the temporal order of actions (Adlam, Vargha-Khadem, Mishkin, & de Haan, 2005). Infants who are at risk for damage to the medial temporal lobe memory system because of adverse fetal environments, also exhibit impairments in recalling the temporal order of imitation sequences (DeBoer, Wewerka, Bauer, Georgieff, & Nelson, 2005).…”

Timely sleep facilitates declarative memory consolidation in infants

“…Deferred imitation procedures assess memory by presenting the infant with a model who demonstrates a series of actions with objects, and measuring the infant's ability to reproduce these actions after a delay (i.e., at test). Deferred imitation is a widely recognized measure of nonverbal declarative memory (22)(23)(24)(25). In Experiment (Exp.)…”