title: Competition and representation during memory retrieval: roles of the prefrontal cortex and the posterior parietal cortex.
abstract: In this functional-MRI study we examined the hypothesis that the prefrontal cortex responds differently to the extent of competition during retrieval, whereas the parietal cortex is responsible for problem representation that should not be directly related to the competition. Participants mastered arbitrary person-location pairs, and their recognition memory was tested in a functional-MRI session. The pairs were constructed such that a person was associated with one, two, or three different locations and vice versa. The recognition time increased with the number of associations, reflecting increased competition. A confirmatory analysis of imaging data with prespecified prefrontal and parietal regions showed that, although both regions were highly involved during memory retrieval, only the prefrontal region responded to the levels of competition. This result was consistent with predictions of an information-processing model as well as with an exploratory identification of regions of interest.
authors.affiliation: Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213, USA. mhsohn@andrew.cmu.edu
authors.forename: Myeong-Ho
authors.initials: MH
authors.lastname: Sohn
authors.forename: Adam
authors.initials: A
authors.lastname: Goode
authors.forename: V Andrew
authors.initials: VA
authors.lastname: Stenger
authors.forename: Cameron S
authors.initials: CS
authors.lastname: Carter
authors.forename: John R
authors.initials: JR
authors.lastname: Anderson
mesh_terms: D000328:Adult; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D008959:Models, Neurological; D008960:Models, Psychological; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*
chemical_list: D010100:Oxygen