Retrieval failure, rehearsal deficiency, and short-term memory loss in the aphasic adult

Studies show that aphasic patients typically are grossly impaired in short-term memory performance. Since aphasics generally experience difficulty in word retrieval, it is conceivable that short-term memory loss is partially the result of verbal rehearsal deficiency which, in turn, is caused by the word retrieval problem. This paper reports an experiment in which five aphasic adults were nonverbally to recall individualized lists of pictures they could easily name and lists of pictures they could not name. Final items in the two lists were recalled with equal accuracy; this was expected in that the recency effect usually reflects sensory rather than verbal storage. Initial items were recalled with greater accuracy than middle-list items in the nameable sets but not in the unnameable sets. This primacy effect suggests the aphasics rehearsed the nameable pictures, but both lists were recalled so poorly that rehearsal deficit was considered responsible for no more than a fraction of the aphasics' reduction in short-term memory.