title: Brain responds to another person's eye blinks in a natural setting-the more empathetic the viewer the stronger the responses.
abstract: An observer's brain is known to respond to another person's small nonverbal signals, such as gaze shifts and eye blinks. Here we aimed to find out how an observer's brain reacts to a speaker's eye blinks in the presence of other audiovisual information. Magnetoencephalographic brain responses along with eye gaze were recorded from 13 adults who watched a video of a person telling a story. The video was presented first without sound (visual), then with sound (audiovisual), and finally the audio story was presented with a still-frame picture on the screen (audio control). The viewers mainly gazed at the eye region of the speaker. Their saccades were suppressed at about 180 ms after the start of the speaker's blinks, a subsequent increase of saccade occurence to the base level, or higher, at around 340 ms. The suppression occurred in visual and audiovisual conditions but not during the control audio presentation. Prominent brain responses to blinks peaked in the viewer's occipital cortex at about 250 ms, with no differences in mean peak amplitudes or latencies between visual and audiovisual conditions. During the audiovisual, but not visual-only, presentation, the responses were the stronger the more empathetic the subject was according to the Empathic Concern score of the Interpersonal Reactivity Index questionnaire (Spearman's rank correlation, 0.73). The other person's eye blinks, nonverbal signs that often go unnoticed, thus elicited clear brain responses even in the presence of attention-attracting audiovisual information from the narrative, with stronger responses in people with higher empathy scores.
authors.affiliation: Brain Research Unit, Department of Neuroscience and Biomedical Engineering, and MEG Core, Aalto NeuroImaging, Aalto University, P.O. Box 15100, 00076, Aalto, Finland.
authors.forename: Anne
authors.initials: A
authors.lastname: Mandel
authors.affiliation: Brain Research Unit, Department of Neuroscience and Biomedical Engineering, and MEG Core, Aalto NeuroImaging, Aalto University, P.O. Box 15100, 00076, Aalto, Finland.
authors.forename: Siiri
authors.initials: S
authors.lastname: Helokunnas
authors.affiliation: Brain Research Unit, Department of Neuroscience and Biomedical Engineering, and MEG Core, Aalto NeuroImaging, Aalto University, P.O. Box 15100, 00076, Aalto, Finland.
authors.forename: Elina
authors.initials: E
authors.lastname: Pihko
authors.affiliation: Brain Research Unit, Department of Neuroscience and Biomedical Engineering, and MEG Core, Aalto NeuroImaging, Aalto University, P.O. Box 15100, 00076, Aalto, Finland.
authors.forename: Riitta
authors.initials: R
authors.lastname: Hari
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001307:Auditory Perception / Q000502:physiology; D001767:Blinking; D001921:Brain / Q000502:physiology*; D004645:Empathy / Q000502:physiology*; D053483:Eye Movement Measurements; D005133:Eye Movements / Q000502:physiology; D000066499:Facial Recognition / Q000502:physiology; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D033262:Narration; D009483:Neuropsychological Tests; D010775:Photic Stimulation / Q000379:methods; D012938:Social Perception; D014741:Video Recording; D055815:Young Adult
keywords: cortex; eye movements; magnetoencephalography; social cognition; visual evoked responses