title: Event-related potential signatures of perceived and imagined emotional and food real-life photos.
abstract: Although food and affective pictures share similar emotional and motivational characteristics, the relationship between the neuronal responses to these stimuli is unclear. Particularly, it is not known whether perceiving and imagining food and affective stimuli elicit similar event-related potential (ERP) patterns. In this study, two ERP correlates, the early posterior negativity (EPN) and the late positive potential (LPP) for perceived and imagined emotional and food photographs were investigated. Thirteen healthy volunteers were exposed to a set of food photos, as well as unpleasant, pleasant, and neutral photos from the International Affective Picture System. In each trial, participants were first asked to view a photo (perception condition), and then to create a visual mental image of it and to rate its vividness (imagery condition). The results showed that during perception, brain regions corresponding to sensorimotor and parietal motivational (defensive and appetitive) systems were activated to different extents, producing a graded pattern of EPN and LPP responses specific to the photo content - more prominent for unpleasant than pleasant and food content. Also, an EPN signature occurred in both conditions for unpleasant content, suggesting that, compared to food or pleasant content, unpleasant content may be attended to more intensely during perception and may be represented more distinctly during imagery. Finally, compared to LLP activation during perception, as well as imagery and perception of all other content, LPP activation was significantly reduced during imagery of unpleasant photos, suggesting inhibition of unwanted memories. Results are framed within a neurocognitive working model of embodied emotions.
authors.affiliation: Department of Psychology, Stockholm University, Stockholm, Sweden.
authors.forename: Fernando
authors.initials: F
authors.lastname: Marmolejo-Ramos
authors.forename: Kim
authors.initials: K
authors.lastname: Hellemans
authors.forename: Amy
authors.initials: A
authors.lastname: Comeau
authors.forename: Adam
authors.initials: A
authors.lastname: Heenan
authors.forename: Andrew
authors.initials: A
authors.lastname: Faulkner
authors.forename: Alfonso
authors.initials: A
authors.lastname: Abizaid
authors.forename: Amedeo
authors.initials: A
authors.lastname: D'Angiulli
mesh_terms: D000328:Adult; D000339:Affect / Q000502:physiology; D001921:Brain / Q000502:physiology*; D004644:Emotions / Q000502:physiology*; D005071:Evoked Potentials; D005260:Female; D005502:Food; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult