Type-specific proactive interference in patients with semantic and phonological STM deficits

Abstract

Prior neuropsychological evidence suggests that semantic and phonological components of short-term memory (STM) are functionally and neurologically distinct. The current paper examines proactive interference (PI) from semantic and phonological information in two STM-impaired patients, DS (semantic STM deficit) and AK (phonological STM deficit). In Experiment 1 probe recognition tasks with open and closed sets of stimuli were used. Phonological PI was assessed using nonword items, and semantic and phonological PI was assessed using words. In Experiment 2 phonological and semantic PI was elicited by an item recognition probe test with stimuli that bore phonological and semantic relations to the probes. The data suggested heightened phonological PI for the semantic STM patient, and exaggerated effects of semantic PI in the phonological STM case. The findings are consistent with an account of extremely rapid decay of activated type-specific representations in cases of severely impaired phonological and semantic STM.

Keywords:

• Proactive interference
• Semantic short-term memory deficits
• Phonological short-term memory deficits
• Phonological proactive interference
• Semantic proactive inteference

Dr Harris is now working as a postdoctoral researcher at King's College London. This work was supported by grants from the National Institute of Health Research and the Stroke Association (UK). We are indebted to DS and AK for their patient and enthusiastic participation in this work. We are grateful to Professor Randi Martin and an anonymous reviewer for their extremely helpful comments on an earlier draft.

Dr Harris is now working as a postdoctoral researcher at King's College London. This work was supported by grants from the National Institute of Health Research and the Stroke Association (UK). We are indebted to DS and AK for their patient and enthusiastic participation in this work. We are grateful to Professor Randi Martin and an anonymous reviewer for their extremely helpful comments on an earlier draft.