Why Language Processing Recruits Modality Specific Brain Regions: It Is Not About Understanding Words, but About Modelling Situations

Abstract

Whether language comprehension requires the participation of brain structures that evolved for perception and action has been a subject of intense debate. While brain-imaging evidence for the involvement of such modality-specific regions has grown, the fact that lesions to these structures do not necessarily erase word knowledge has invited the conclusion that language-induced activity in these structures might not be essential for word recognition. Why language processing recruits these structures remains unanswered, however. Here, we examine the original findings from a slightly different perspective. We first consider the 'original' function of structures in modality-specific brain regions that are recruited by language activity. We propose that these structures help elaborate 'internal forward models' in motor control (c.f. emulators). Emulators are brain systems that capture the relationship between an action and its sensory consequences. During language processing emulators could thus allow accessing associative memories. We further postulate the existence of a linguistic system that exploits, in a rule-based manner, emulators and other nonlinguistic brain systems, to gain complementary (and redundant) information during language processing. Emulators are therefore just one of several sources of information. We emphasize that whether a given word-form triggers activity in modality-specific brain regions depends on the linguistic context and not on the word-form as such. The role of modality-specific systems in language processing is thus not to help understanding words but to model the verbally depicted situation by supplying memorized context information. We present a model derived from these assumptions and provide predictions and perspectives for future research.

Factives at hand: When presupposition mode affects motor response.

“…Again, this challenges the claim that action word meaning automatically recruit motor semantic features and that sensorimotor processing is necessary for conceptual or language processing. Our results are thus compatible with an account that assumes context dependency of language-induced motor activity (see Cayol and Nazir, 2020). The The implications of the studies presented in this paper go beyond the debate on embodiment, and directly address questions that are relevant to linguistics theories.…”

“…Overall, independently of the fact that the Asserted Action, the Non-Action, and the Presupposed conditions differ on several dimensions (see the previous discussion section), the results of the two experiments together confirm that action-related verbs in themselves are not sufficient to generate a motor response and that the linguistic environment plays a crucial role (e.g. Cayol & Nazir, 2020;Willems & Casasanto, 2011).…”

“…Tomasino & Rumiati, 2013, for a meta-analysis regarding the neuroscientific evidence, see e.g., Watson, Cardillo, Ianni, & Chatterjee, 2013). However, as recently proposed by Cayol & Nazir (2020), the activation of modality-specific brain regions during language processing may not be necessary, but can aide to optimize simulations, in cases "in which the action/perception is 'veridical' and/or the 'linguistic focus' of the verbally depicted situation" (p. 14 In short, while there is little doubt that under certain contextual conditions language processing recruits sensorimotor structures of the brain, the function of this activity is yet to be specified. For a better understanding, it is therefore worth expanding these findings and examining further linguistic conditions that make use of motor brain structures in order to uncover the underlying mechanisms.…”

Brain Responses to Hypnotic Verbal Suggestions Predict Pain Modulation

“…To explain language processing in situation modeling, Cayol and Nazir ( 10 ) proposed that the brain acts as an emulator that “captures the relationship between an action and its sensory consequences.” Anchored in feedforward models of motor control ( 11 ), this emulator generating predictions that guide the processing of sensory input provides a model of the mechanisms underlying the neural activity behind verbal integration that we may observe in hypnosis. By illustrating how language affects perception processes, this model provides a potential basis for relating semantic processing to learning optimization ( 12 ).…”

Imaginary Worlds and Their Borders: An Opinion Article

“…Another vivid example comes from research on embodied cognition. Sensorimotor areas of the brain are active in processing longer narratives (for review, see Meteyard et al, 2012; see also Fischer and Zwaan, 2008;Cayol and Nazir, 2020)-the so-called mental simulation. By exposing their readers to a long narrative, describing physical sensations from different modalities (such as vision, touch, smell, taste, or even interoception-see Connell et al, 2018), the author activates embodied experiential traces in readers' brains as if the readers see, hear or act in the described environment.…”