title: The neural bases of the effects of item-nonspecific proactive interference in working memory.
abstract: We reanalyzed the behavioral and fMRI data from seven previously published studies of working memory in order to assess the behavioral and neural effects of item-nonspecific proactive interference (PI; attributable to the accrual of antecedent information independent of the repetition of particular items). We hypothesized that item-nonspecific PI, implicated in age-related declines in working memory performance, is mediated by the same mechanism(s) that mediate item-specific PI (occurring when an invalid memory probe matches a memorandum from the previous trial). Reaction time increased across trials as a function of position within the block, a trend that reversed across the duration of each multiblock experiment. The fMRI analyses revealed sensitivity to item-nonspecific PI during the probe epoch in the left anterior inferior frontal gyrus and the left dorsolateral prefrontal cortex(PFC). They also revealed a negative trend, across trials, in the transient probe-evoked component of the global signal. A common PFC-based mechanism may mediate many forms of PI.
authors.affiliation: University of Wisconsin, Madison, Wisconsin, USA. postle@wisc.edu
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Postle
authors.forename: Lauren N
authors.initials: LN
authors.lastname: Brush
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008606:Mental Processes / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology*; D011334:Proactive Inhibition; D011930:Reaction Time / Q000502:physiology*; D012016:Reference Values; D012189:Retrospective Studies