title: Electrophysiological evidence for enhanced representation of food stimuli in working memory.
abstract: Studies from our laboratory have shown that, relative to neutral objects, food-related objects kept in working memory (WM) are particularly effective in guiding attention to food stimuli (Higgs et al. in Appetite, 2012). Here, we used electrophysiological measurements to investigate the neural representation of food versus non-food items in WM. Subjects were presented with a cue (food or non-food item) to either attend to or hold in WM. Subsequently, they had to search for a target, while the target and distractor were each flanked by a picture of a food or non-food item. Behavioural data showed that a food cue held in WM modulated the deployment of visual attention to a search target more than a non-food cue, even though the cue was irrelevant for target selection. Electrophysiological measures of attention, memory and retention of memory (the P3, LPP and SPCN components) were larger when food was kept in WM, compared to non-food items. No such effect was observed in a priming task, when the initial cue was merely identified. Overall, our electrophysiological data are consistent with the suggestion that food stimuli are particularly strongly represented in the WM system.
authors.affiliation: School of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK, f.rutters@vumc.nl.
authors.forename: Femke
authors.initials: F
authors.lastname: Rutters
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kumar
authors.forename: Suzanne
authors.initials: S
authors.lastname: Higgs
authors.forename: Glyn W
authors.initials: GW
authors.lastname: Humphreys
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001245:Association Learning / Q000502:physiology; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D003463:Cues; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D005502:Food; D007839:Functional Laterality; D006801:Humans; D007600:Judgment / Q000502:physiology; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012153:Retention, Psychology; D013997:Time Factors; D064232:Visual Analog Scale; D055815:Young Adult