“While this story seems plausible, it is by no means proven. However, it suggests several directions for future research" (84). They are providing a base upon which to test their hypothesis with neuroscientific falsibility criteria.
Also see Rohrer’s chapter beginning at 165. His abstract is more assertive than the previous reference:
"A focus on the brain as an organic biological entity that grows and develops as the organism does is a prerequisite to a neurally-plausible theory of how image schemata structure language. Convergent evidence from the cognitive neurosciences has begun to establish the neural basis of image schemata as dynamic activation patterns that are shared across the neural maps of the sensorimotor cortex. First, I discuss the numerous experimental studies on normal subjects that, coupled with recent neurological studies of body-part language deficits in patients, have begun to establish that the sensorimotor cortices are crucial to the semantic comprehension of bodily action terms and sentences. Second, by tracing the cognitive and neural development of image schemata through both animal neuroanatomical studies and human neuroimaging studies, I review the neurobiologically plausible bases for image schemata. I propose that Edelman’s theory of secondary neural repertoires is the likeliest process to account for how integrative areas of the sensorimotor cortex can develop both sensorimotor and image schematic functions. Third, I assess the evidence from recent fMRI and ERP experiments showing that literal and metaphoric language stimuli activate areas of sensorimotor cortex consonant with the image schemata hypothesis. I conclude that these emerging bodies of evidence show how the image schematic functions of the sensorimotor cortex structure linguistic expression and metaphor.”
He concludes: “Taken together, the converging results of these studies show that we now have an emerging body of compelling evidence which supports that the hypothesis that our semantic understanding takes place via image schemata located in the same cortical areas which are already known to map sensorimotor activity” (186).