The effect of social proximity on fear conditioning: A virtual reality study

Invasions of personal space automatically trigger fearful responses and yet little is known about the relationship between personal space and fear conditioning. We hypothesized that fear extinction would be weakened and fear renewal would be strengthened for a human avatar invading participants’ personal space as compared to a human avatar safely outside of participants’ personal space. We tested this hypothesis using a within-subject (n = 15) design wherein four human avatars, two close and two far, appeared in front of participants while they traveled down a virtual reality environment that appeared like a long hallway. During the acquisition phase, one human avatar from each distance was paired with mild electrical stimulation. The context of the virtual reality environment changed during the extinction phase and then returned to its original state in order to test contextual renewal after extinction. We found no significant differences in skin conductance responses between human avatars in the extinction phase, but we did find a main effect of distance ((F(1,14) = 13.043, p = 0.003) and a significant interaction effect between distance and CS type (F(1,14) = 8.66, p = 0.012) during renewal. Thus context and personal space interact during return of fear phenomena. These findings have implications for our understanding and treatment of PTSD.