Embodied Semantics

Embodiment holds that cognition is rooted in physical interactions with the environment, and that abstract mental representations are both formed out of, and retain their

connections to, lived experiences, perceptions, and actions. A key feature of grounded or embodied cognition is that it opposes the assertion that abstract thought exists amodally, or separately from physical perceptions and experiences, in semantic memory (Barsalou, 2008; Casasanto, 2011; Glenberg, 1997; Meteyard et al., 2012; van Dam, van Dijk, Bekkering, & Rueschmeyer, 2012). Wilson (2002) explored embodiment as an update of

the Piagetian view that the maturation of cognitive abilities can be traced throughout sensorimotor development, emphasizing the vital roles of sensory, perceptual, and motor systems in offline reasoning when the physical things to which they refer are temporally or physically removed. Wilson’s observation that offline embodied cognition downloads information to these systems from working memory suggests that deficits in perceptual systems that are seen in NLD would have cascading effects, even in the absence of working memory deficits11.

Piaget’s theory was one source for Rourke’s contention (1989) that children with NLD have impoverished semantic representations as a consequence of sensorimotor deficits, as outlined at the outset of this chapter. This suggestion was supported even in an adult sample, where differences in semantic depth coincided with perceptual deficits; current theories of embodiment provided a conceptual link. Gibbs (2013) presented a detailed account of the contribution of embodiment to language, in particular metaphor

perception. He reviewed brain imaging studies, largely with adults, which found activation in appropriate motor and somatosensory brain regions to the presentation of action and sensory words, either singly or embedded in sentences; this is known as semantic somatotopy. For example, known neural correlates of movement of the legs were seen with written presentation of kicking a ball and kicking a habit in a cortical area known as the pre-motor cortex, using fMRI (Boulenger, Hauk, & Pulvermüller, 2009). Regional patterns of neural activation also distinguished between arm and leg activations for grasping an idea and kicking a habit, demonstrating a link between perceptual neural systems and their linguistic incarnations that has supported the embodied account of language comprehension (Aziz-Zadeh & Damasio, 2008; Barsalou, 2008), and extending that account to metaphors (Boulenger et al., 2009).

Not all imaging studies have found semantic somatotopy effects for metaphorical language. Aziz-Zadeh and colleagues speculated that an absence of the effect in their

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Working memory tests were not included in this set of studies. Verbal working memory has not been implicated as a weakness in NLD, although visual working memory impairments are common

research may have been related to the familiarity of metaphors that were used, such as bite the bullet or kick the bucket, in which over-learned associations may no longer activate motor cortex, but instead be accessed directly as stored linguistic conventions (Aziz-Zadeh & Damasio, 2008). As noted previously, these idiomatic, possibly amodal representations have been termed collocations in other research (Molinaras & Carreiras, 2010). Gibbs also cautioned that the overall question of how well embodied aspects of conceptual metaphor theory account for metaphor comprehension cannot be summarized simply. Experimental results have depended on choice of participants, materials,

experimental task, and the ways in which metaphor understanding is operationalized. Similarly, a review by Louwerse and colleagues (Louwerse, Hutchinson, Tillman, & Recchia, 2015) found that the use of perceptually based semantic representations was based in part on individual preferences, as well as experimental contingencies. According to these authors, accessing and manipulating semantic representations has been shown to rely on statistical properties (e.g., how often does this word occur with another), and on underlying modal or embodied relationships. The Symbol

Interdependency Hypothesis emphasized the coordination of symbolic with modal perspectives, proposing that the former view holds during quick processing when “good- enough representations” (p. 432) are used, and the latter is necessary for detailed, in- depth understanding. This hypothesis more easily allowed the application of embodiment to the present results. Frequent use of collocations, in concert with shallow semantic representations for polysemous words, supports the interpretation that individuals with lower scores for gestalt perception and Estimation relied more heavily on amodal, or good-enough, representations than did controls, whose scores for these variables indicated no difficulty interacting with and making inferences about the environment. An observational example illustrated how an embodied perspective would function here. A participant with NLD named river bank as a meaning for bank, tracing its shape with her hands, but could not articulate a synonym such as slope, or edge. This participant felt that she could not find the word that she believed she had stored for this feature.

Alternatively, it was possible that the participant had not actually formed a modal semantic representation for river bank, and only had the noun phrase river bank in her memory. She may not have connected disparate exposures to the term slope, for example

in a mathematics class, or judging the angle of a hill to climb, and thus did not have a full semantic representation of the gradual incline at the edge of a river. In another instance, a participant could not retrieve a synonym for a “point in sports”, rejecting his own suggestion of tally and not being able to name others. It was possible that this participant had filed separate meanings for discrete words like point, score, goal, and tally. This suggested another way in which the word knowledge in these participants may vary, in which representations are more definitive or categorical, and less linked than may be typical1. In these and other cases, participants believed that they knew the words for which they were searching, but they may have been relying on either impoverished or overly restricted semantic representations. The application of embodied semantics, particularly as described by Louwerse et al. (2015), fits the pattern of quantitative results and qualitative observations in the present work.