title: Differential patterns of prefrontal MEG activation during verbal & visual encoding and retrieval.
abstract: The spatiotemporal profile of activation of the prefrontal cortex in verbal and non-verbal recognition memory was examined using magnetoencephalography (MEG). Sixteen neurologically healthy right-handed participants were scanned whilst carrying out a modified version of the Doors and People Test of recognition memory. A pattern of significant prefrontal activity was found for non-verbal and verbal encoding and recognition. During the encoding, verbal stimuli activated an area in the left ventromedial prefrontal cortex, and non-verbal stimuli activated an area in the right. A region in the left dorsolateral prefrontal cortex also showed significant activation during the encoding of non-verbal stimuli. Both verbal and non-verbal stimuli significantly activated an area in the right dorsomedial prefrontal cortex and the right anterior prefrontal cortex during successful recognition, however these areas showed temporally distinct activation dependent on material, with non-verbal showing activation earlier than verbal stimuli. Additionally, non-verbal material activated an area in the left anterior prefrontal cortex during recognition. These findings suggest a material-specific laterality in the ventromedial prefrontal cortex during encoding for verbal and non-verbal but also support the HERA model for verbal material. The discovery of two process dependent areas during recognition that showed patterns of temporal activation dependent on material demonstrates the need for the application of more temporally sensitive techniques to the involvement of the prefrontal cortex in recognition memory.
authors.affiliation: York NeuroImaging Centre, University of York, York, United Kingdom.
authors.forename: Garreth
authors.initials: G
authors.lastname: Prendergast
authors.affiliation: Department of Psychology, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Eve
authors.initials: E
authors.lastname: Limbrick-Oldfield
authors.affiliation: Department of Psychology, University of York, York, United Kingdom.
authors.forename: Ed
authors.initials: E
authors.lastname: Ingamells
authors.affiliation: Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Susan
authors.initials: S
authors.lastname: Gathercole
authors.affiliation: Department of Psychology, University of York, York, United Kingdom.
authors.forename: Alan
authors.initials: A
authors.lastname: Baddeley
authors.affiliation: York NeuroImaging Centre, University of York, York, United Kingdom.
authors.forename: Gary G R
authors.initials: GG
authors.lastname: Green
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology; D010364:Pattern Recognition, Visual; D017397:Prefrontal Cortex / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*; D014706:Verbal Learning / Q000502:physiology*; D055815:Young Adult