Dissociable controlled retrieval and generalized selection mechanisms in ventrolateral prefrontal cortex.
How does ventrolateral prefrontal cortex (VLPFC) control mnemonic processing? Alternative models propose that VLPFC guides top-down (controlled) retrieval of knowledge from long-term stores or selects goal-relevant products of retrieval from among competitors. A paucity of evidence supports a retrieval/selection distinction, raising the possibility that these models reduce to a common mechanism. Here, four manipulations varied semantic control demands during fMRI: judgment specificity, cue-target-associative strength, competitor dominance, and number of competitors. Factor analysis revealed evidence for a metafactor that accounted for common behavioral variance across manipulations and for functional variance in left mid-VLPFC. These data support a generalized control process that selects relevant knowledge from among competitors. By contrast, left anterior VLPFC and middle temporal cortex were sensitive to cue-target-associative strength, but not competition, consistent with a control process that retrieves knowledge stored in lateral temporal cortex. Distinct PFC mechanisms mediate top-down retrieval and postretrieval selection.
Badre
David
D
Department of Psychology and Neurosciences Program, Stanford University, Stanford, California 94305, USA. badred@mit.edu
Poldrack
Russell A
RA
Paré-Blagoev
E Juliana
EJ
Insler
Rachel Z
RZ
Wagner
Anthony D
AD
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D003463:Cues; D005163:Factor Analysis, Statistical; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D005793:Generalization, Psychological / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007600:Judgment / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000098:blood supply / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012660:Semantics
D010100:Oxygen