32220
Effect of Intranasal Oxytocin on Visual Processing and Salience of Human Faces
Poster Presentation
Thursday, May 2, 2019: 5:30 PM-7:00 PM
Room: 710 (Palais des congres de Montreal)
L. Westberg1, D. Hovey2, S. Leknes3, B. Laeng3 and L. Martens3, (1)University of Gothenburg, Gothenburg, Sweden, (2)Department of Pharmacology, University of Gothenburg, Gothenburg, Sweden, (3)Department of Psychology, University of Oslo, Oslo, Norway
Background: There is still no pharmacological treatment available for improving the core symptoms of autism. Promise has emerged from studies showing that treatment with the neuropeptide oxytocin promotes attention to social cues, and alleviates autism symptoms in patients. However, the underlying mechanisms of oxytocin’s actions remain undetermined. Social salience hypothesis suggest that oxytocin increases the salience of social cues, which in turn can modulate the influence of context and inter-individual factors on social behavior. Salience of cues can be manipulated through binocular rivalry, a visual phenomenon that has been extensively used to study visual perception. In a binocular rivalry paradigm the eyes are presented with two discordant images, that compete for visual awareness – i.e. each eye is continuously exposed to only one of two images, but the image that the viewer subjectively perceives is one or the other (“dominant” percept), or a mix of the two (“piecemeal” percept).
Objectives: This study investigates if oxytocin treatment may affect binocular rivalry, a measure of visual perception and interplay of excitation and inhibition in the cortex. Binocular rivalry has been previously shown to be deficient in individuals with autism.
Methods: We recruited 50 male volunteers, and carried out a randomized, double-blinded, cross-over study of the effects of intranasal oxytocin on binocular rivalry. The participants viewed images of social stimuli (faces with different emotional expressions) and non-social stimuli (houses and Gabor patches) as salience of social cues was quantified using duration of dominance for social and non-social stimuli.
Results: We demonstrate a robust effect that intranasal oxytocin increases the salience of human faces in binocular rivalry, such that dominance durations of faces are longer – this effect is not modulated by the facial expression. We tentatively also show that oxytocin treatment increases dominance durations for non-social stimuli.
Conclusions: Our results lend support to the social salience hypothesis of oxytocin, and in addition offer provisional support for the role of oxytocin in influencing excitation-inhibition balance in the brain.
