Affective touch during the processing of angry facial expressions: an event-related potential study

It has been shown that affective touch can have stress-buffering effects. The current event-related potential (ERP) study investigated whether affective touch can reduce emotional distress and associated late positivity while viewing angry facial expressions. A total of 122 females (mean age = 23 years) were randomly assigned to one of three groups to either receive slow/soft brushing of their forearm (affective touch), fast brushing (nonaffective touch), or no touch while viewing images depicting angry and neutral facial expressions. The participants rated their affective state (valence, arousal) before and after the experiment. They also rated the perceived intensity of the angry facial expressions and the pleasantness of touch during the experiment. Components of the Late Positive Potential (LPP) in response to the images that are associated with stimulus significance, attention allocation, and emotion regulation (early LPP: 400-1000 ms; late LPP: 1000-3000 ms) were extracted for a frontal and a centroparietal cluster. Affective touch was associated with reduced amplitudes of the late LPP in the frontal cluster but did not affect centroparietal LPPs (early, late). Affective touch was rated as more pleasant than nonaffective touch but did not change reported valence, arousal, and perceived anger intensity. In conclusion, affective touch modulated a neural indicator of stimulus significance but did not influence self-report measures. More naturalistic touch settings might enhance the effects.