Studies of the classic exteroceptive sensory systems (e.g., vision, touch) consistently demonstrate that
vividly imagining a sensory experience of the world – simulating it – is associated with increased
activity in the corresponding primary sensory cortex. We hypothesized, analogously, that simulating
internal bodily sensations would be associated with increased neural activity in primary interoceptive
cortex. An immersive, language-based mental imagery paradigm was used to test this hypothesis (e.g.,
imagine your heart pounding during a roller coaster ride, your face drenched in sweat during a
workout). During two neuroimaging experiments, participants listened to vividly described situations
and imagined “being there” in each scenario. In Study 1, we observed significantly heightened activity
in primary interoceptive cortex (of dorsal posterior insula) during imagined experiences involving
vivid internal sensations. This effect was specific to interoceptive simulation: it was not observed
during a separate affect focus condition in Study 1, nor during an independent Study 2 that did not
involve detailed simulation of internal sensations (instead involving simulation of other sensory
experiences). These findings underscore the large-scale predictive architecture of the brain and reveal
that words can be powerful drivers of bodily experiences
