Associations between the oxytocin receptor gene (OXTR) rs53576 polymorphism and emotional processing of social and nonsocial cues: an event-related potential (ERP) study

BACKGROUND: Oxytocin receptor (OXTR) gene polymorphisms are related to individual differences in emotional processing of social cues. However, whether OXTR polymorphisms affect emotional processing of nonsocial cues remains unclear. The present study investigated the relationship between the OXTR rs53576 polymorphism and emotional processing of social cues and nonsocial cues. METHODS: Event-related potentials were recorded from 88 male participants while images of humans and images of objects were presented as social cues and nonsocial cues, respectively. RESULTS: First, the results showed that GG carriers of OXTR rs53576 showed more negative N1 (50–200 ms) than AA carriers in response to images of both humans and objects. Second, GG carriers showed more negative N2 (200–320 ms) than AA carriers in response to images of humans but not in response to images of objects. Third, GG carriers showed more negative N2 in response to images of humans than images of objects, whereas AA carriers showed the opposite pattern. Fourth, we observed no difference in late positive potential (600–1000 ms) to images of humans or objects that depended on the OXTR rs53576 polymorphism. CONCLUSIONS: These results suggest that the OXTR rs53576 polymorphism affects emotional processing of not only social cues but also nonsocial cues in the very early stage (reflected in N1); however, the data also suggest that the OXTR rs53576 polymorphism is related specifically to increased emotional processing of social cues in the middle stage (reflected in N2).