PET evidence for an amodal verbal working memory system.
Current models of verbal working memory assume that modality-specific representations are translated into phonological representations before entering the working memory system. We report an experiment that tests this assumption. Positron emission tomography measures were taken while subjects performed a verbal working memory task. Stimuli were presented either visually or aurally, and a visual or auditory search tasks, respectively, was used as a control. Results revealed an almost complete overlap between the active memory areas regardless of input modality. These areas included dorsolateral frontal, Broca's area, SMA, and premotor cortex in the left hemisphere; bilateral superior and posterior parietal cortices and anterior cingulate; and right cerebellum. These results correspond well with previous research and suggest that verbal working memory is modality independent and is mediated by a circuit involving frontal, parietal, and cerebellar mechanisms.
Schumacher
E H
EH
Department of Psychology, University of Michigan, Ann Arbor 48109, USA. eschu@umich.edu
Lauber
E
E
Awh
E
E
Jonides
J
J
Smith
E E
EE
Koeppe
R A
RA
D000328:Adult; D001931:Brain Mapping / Q000295:instrumentation*; D002531:Cerebellum / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology; D010700:Phonetics; D012016:Reference Values; D012153:Retention, Psychology / Q000502:physiology; D013067:Speech Perception / Q000502:physiology; D014055:Tomography, Emission-Computed / Q000295:instrumentation*; D014706:Verbal Learning / Q000502:physiology*