Fear in action: Fear conditioning and alleviation through body movements

Fear memories enhance survival especially when the memories guide
defensive movements to minimize harm. Accordingly, fear memories and body
movements have tight relationships in animals: Fear memory acquisition
results in adapting reactive defense movements, while training active
defense movements reduces fear memory. However, evidence in humans is
scarce because their movements are typically suppressed in experiments.
Here, we tracked adult participants’ body motions while they underwent
ecologically-valid fear conditioning in a 3D virtual space. First, with
body motion tracking, we revealed that distinct spatiotemporal body
movement patterns emerge through fear conditioning. Second, subsequent
training to actively avoid threats with naturalistic defensive actions led
to a long-term (24 hrs) reduction of physiological and embodied
conditioned responses, while extinction or vicarious training only
transiently reduced the responses. Together, our results highlight the
role of body movements in human fear memory and its intervention.