Publication Type Academic Article
Authors Ragland J, Turetsky B, Gur R, Gunning-Dixon F, Turner T, Schroeder L, Chan R, Gur R
Journal Neuropsychology
Volume 16
Issue 3
Pagination 370-9
Date Published 07/01/2002
ISSN 0894-4105
Keywords Brain, Magnetic Resonance Imaging, Memory
Abstract n-back letter and fractal tasks were administered to 11 participants during functional magnetic resonance imaging to test process specificity theories of prefrontal cortex (PFC) function and assess task validity. Tasks were matched on accuracy, but fractal n-back responses were slower and more conservative. Maintenance (1-back minus 0-back) activated inferior parietal and dorsolateral PFC, with additional activation in right ventrolateral PFC during letter n-back and left lingual gyrus during fractal n-back. Maintenance plus manipulation (2-back minus 0-back) activated inferior parietal, Broca's area, insula, and dorsolateral and ventral PFC, with greater right dorsolateral PFC activation for letter n-back. Manipulation only (2-back minus 1-back) produced additional and equivalent dorsolateral PFC and anterior cingulate activation in both tasks. Results support fractal n-back validity and indicate substantial overlap in working memory functions of dorsal and ventral PFC.
PubMed ID 12146684
PubMed Central ID PMC4332798
Back to Top