Functional significance of retrieval-related activity in lateral parietal cortex: Evidence from fMRI and ERPs

• Published in: Human brain mapping Vol. 30; no. 5; pp. 1490 - 1501
• Main Authors: Vilberg, Kaia L., Rugg, Michael D.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.05.2009; Wiley-Liss
• Subjects: Adolescent; Analysis of Variance; Biological and medical sciences; Brain Mapping; Electrodiagnosis. Electric activity recording; Electroencephalography; episodic buffer; episodic memory; event-related potential; Evoked Potentials, Visual - physiology; Female; Humans; Image Processing, Computer-Assisted - methods; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging; Male; Medical sciences; Mental Recall - physiology; Nervous system; Neuropsychological Tests; Oxygen - blood; Parietal Lobe - blood supply; Parietal Lobe - physiology; Photic Stimulation - methods; Psychomotor Performance - physiology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Reaction Time - physiology; recognition memory; remember-know; Time Factors; Young Adult; Nervous system diseases; Recognition memory; remember-know; Radiodiagnosis; Central nervous system; Electrophysiology; event-related potential; Nuclear magnetic resonance imaging; Encephalon; Parietal cortex; episodic buffer; Episodic memory; Event evoked potential
• ISSN: 1065-9471; 1097-0193
• DOI: 10.1002/hbm.20618

The present study addressed the question whether neural activity in left lateral parietal cortex is modulated by amount of information recollected. In two experiments (one using fMRI and the other ERPs), subjects first studied pairs of pictures presented for either 1 or 6 s. They then performed a standard “Remember/Know” recognition memory test in which the old items comprised one of the pictures from each studied pair. In both experiments, a surprise posttest indicated that subjects recollected more details about the study presentation of the items presented for the longer duration. In the fMRI experiment, recollection‐ and familiarity‐based recognition elicited activity in distinct cortical networks. Additionally, recollection‐related activity in left inferior parietal cortex was of greater magnitude for test items presented for 6 s than for 1 s. In the ERP study the “left‐parietal old/new effect”—a putative correlate of successful recollection—was likewise modulated by amount of information retrieved. Together, these findings provide further support for dual‐process models of recognition memory and add weight to the proposal that retrieval‐related activity in left inferior parietal cortex reflects processes supporting the online representation of retrieved episodic information. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.