Control processes in verbal working memory: an event-related potential study.
Event-related potentials (ERPs) were recorded using a large electrode array while subjects engaged in tasks designed to dissociate control from storage/maintenance processes in verbal working memory (WM). Increased ERP negativity (450-900 ms post-stimulus onset) over left frontal regions emerged only when required dynamic updating/revision of WM stores was initiated, with augmentation of right frontal negativity in the same epoch relative to more general overall task demands. Increased ERP positivity in a similar time window over parietal regions reflected initiation of required rehearsal/maintenance of memory set contents, with progressive amplitude increases with repeated dynamic updating/revision of memory stores, suggesting increased effortful activity to resist proactive interference effects. These findings are consistent with a left frontal-parietal network for process control in verbal working memory.
Kiss
Ivan
I
Lakeridge Health Corporation, Oshawa, ON, Canada. ivankiss@rogers.com
Watter
Scott
S
Heisz
Jennifer J
JJ
Shedden
Judith M
JM
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D004569:Electroencephalography / Q000379:methods; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D014706:Verbal Learning / Q000502:physiology*