Increasing contextual demand modulates anterior and lateral prefrontal brain regions associated with proactive interference.
Using a parametric version of a modified item-recognition paradigm with three different load levels and by means of event-related functional magnetic resonance imaging, this study tested the hypothesis that cerebral activation associated with intratrial proactive interference (PI) during working memory retrieval is influenced by increased context processing. We found activation of left BA 45 during interference trials across all levels of cognitive processing, and left lateralized activation of the dorsolateral prefrontal cortex (DLPFC, BA 9/46) and the frontopolar cortex (FPC, BA 10) with increasing contextual load. Compared with high susceptibility to PI, low susceptibility was associated with activation of the left DLPFC. These results suggest that an intratrial PI effect can be modulated by increasing context processing of a transiently relevant stimulus set. Moreover, PI resolution associated with increasing context load involves multiple prefrontal regions including the ventro- and dorsolateral prefrontal cortex as well as frontopolar brain areas. Furthermore, low susceptibility to PI might be influenced by increased executive control exerted by the DLPFC.
Department of Psychiatry and Psychotherapy III, University of Ulm, Ulm, Germany. christian.wolf@uni-ulm.de
Robert Christian
RC
Wolf
Henrik
H
Walter
Nenad
N
Vasic
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000098:blood supply / Q000502:physiology*; D011334:Proactive Inhibition; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
D010100:Oxygen