title: The cerebral correlates of subliminal emotions: an eleoencephalographic study with emotional hybrid faces.
abstract: In a high-resolution electroencephalographic study, participants evaluated the friendliness level of upright and inverted 'hybrid faces', i.e. facial photos containing a subliminal emotional core in the low spatial frequencies (< 6 cycles/image), superimposed on a neutral expression in the rest of the spatial frequencies. Upright happy and angry faces were judged as more friendly or less friendly than neutral faces, respectively. We observed the time course of cerebral correlates of these stimuli with event-related potentials (ERPs), confirming that hybrid faces elicited the posterior emotion-related and face-related components (P1, N170 and P2), previously shown to be engaged by non-subliminal emotional stimuli. In addition, these components were stronger in the right hemisphere and were both enhanced and delayed by face inversion. A frontal positivity (210-300 ms) was stronger for emotional than for neutral faces, and for upright than for inverted faces. Hence, hybrid faces represent an original approach in the study of subliminal emotions, which appears promising for investigating their electrophysiological correlates.
authors.affiliation: Department of Neuroscience, Imaging and Clinical Science, 'G. d'Annunzio' University of Chieti-Pescara, Blocco A, Via dei Vestini 31, I-66013, Chieti, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Prete
authors.affiliation: Department of Neuroscience, Imaging and Clinical Science, 'G. d'Annunzio' University of Chieti-Pescara, Blocco A, Via dei Vestini 31, I-66013, Chieti, Italy.|Institute for Advanced Biomedical Technologies, 'G. d'Annunzio' University of Chieti-Pescara, Chieti, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Capotosto
authors.affiliation: Department of Neuroscience, Imaging and Clinical Science, 'G. d'Annunzio' University of Chieti-Pescara, Blocco A, Via dei Vestini 31, I-66013, Chieti, Italy.|Institute for Advanced Biomedical Technologies, 'G. d'Annunzio' University of Chieti-Pescara, Chieti, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Zappasodi
authors.affiliation: Department of Psychology, University of Oslo, Oslo, Norway.
authors.forename: Bruno
authors.initials: B
authors.lastname: Laeng
authors.affiliation: Department of Psychological Science, Health and Territory, 'G. d'Annunzio' University of Chieti-Pescara, Chieti, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Tommasi
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology*; D005071:Evoked Potentials; D005145:Face; D005149:Facial Expression; D000066499:Facial Recognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology; D008297:Male; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D011930:Reaction Time; D055815:Young Adult
keywords: consciousness; event-related brain potentials; face processing; spatial frequencies; subliminal emotions