Our brain's grasp of metaphors grounded in perception?

Theories of grounded cognition suggest that knowledge is represented in modal systems derived from perception (rather than abstract brain codes) and that cognition depends on perceptual simulations. Conceptual metaphor theory is one approach to grounded cognition which suggests that knowledge is structured by metaphorical mappings from sensory experience. Sathian and colleagues do a interesting experiment in which they find that textural metaphors — phrases like "soft-hearted"— turn on a part of the brain (the parietal operculum) that's important to the sense of touch. This doesn't happen with literal counterparts: "he is wet behind the ears" versus "he is naïve," for example, or "it was a hairy situation" versus "it was a precarious situation."

Figure - Touching actives areas shown in yellow and red. Textural metaphors also trigger a reaction (shown in green and, where overlapping, brown) in the parietal operculum.

It would be interesting to see if a subject's appreciation of a tactile metaphor was compromised by transcranial magnetic stimulation that disrupted activity of the parietal operculum.