The Role of Inferior Parietal and Inferior Frontal Cortex in Working Memory

• Published in: Neuropsychology Vol. 20; no. 5; pp. 529 - 538
• Main Authors: Baldo, Juliana V, Dronkers, Nina F
• Format: Journal Article
• Language: English
• Published: Washington, DC American Psychological Association 01-09-2006
• Subjects: Adult; Aged; Anatomical correlates of behavior; Aphasia - psychology; Behavioral psychophysiology; Biological and medical sciences; Education; Female; Frontal Lobe; Frontal Lobe - pathology; Frontal Lobe - physiopathology; Fundamental and applied biological sciences. Psychology; Human; Humans; Language; Learning. Memory; Magnetic Resonance Imaging; Male; Memory; Memory, Short-Term - physiology; Middle Aged; Parietal Lobe; Parietal Lobe - pathology; Parietal Lobe - physiopathology; Phonology; Practice; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Reading; Short Term Memory; Stroke - pathology; Stroke - psychology; Verbal Learning - physiology; phonological storage; frontal cortex; parietal cortex; working memory; articulatory rehearsal; Human; Central nervous system; Cognition; Frontal cortex; Encephalon; Storage; Language; Parietal cortex; Phonology; Parietal lobe; Working memory
• ISSN: 0894-4105; 1931-1559
• DOI: 10.1037/0894-4105.20.5.529

Verbal working memory involves two major components: a phonological store that holds auditory-verbal information very briefly and an articulatory rehearsal process that allows that information to be refreshed and thus held longer in short-term memory (
A. Baddeley, 1996
,
2000
;
A. Baddeley & G. Hitch, 1974
). In the current study, the authors tested two groups of patients who were chosen on the basis of their relatively focal lesions in the inferior parietal (IP) cortex or inferior frontal (IF) cortex. Patients were tested on a series of tasks that have been previously shown to tap phonological storage (span, auditory rhyming, and repetition) and articulatory rehearsal (visual rhyming and a 2-back task). As predicted, IP patients were disproportionately impaired on the span, rhyming, and repetition tasks and thus demonstrated a phonological storage deficit. IF patients, however, did not show impairment on these storage tasks but did exhibit impairment on the visual rhyming task, which requires articulatory rehearsal. These findings lend further support to the working memory model and provide evidence of the roles of IP and IF cortex in separable working memory processes.