Kemmerer’s critical review of my book The Myth of Mirror Neurons raises some important points regarding the relation between motor-centric and motor-modulatory models of perception and understanding. In addressing his critiques I hope to clarify that there is growing agreement that motor-centric models are untenable, while motor-modulatory models are viable but still face theoretical and empirical hurdles.

Expressives like damn convey a negative attitude toward an entity or toward a situation. What is particularly interesting about such expressions is the looseness of the relation between their syntax, which is the syntax of normal attribute adjectives, and their interpretation (Potts 2005, 2007). An experiment on various negative expressives manipulated the placement of the expressive as a prior utterance, or inside the subject or inside an object of the verb or preposition. Experimental participants were asked what the speaker was most likely to have a negative attitude towards − the subject, the object, or the entire situation. The test items were of two types, ‘non-causal’ and ‘causal’, exemplified by The holiday is on the damn weekend and The dog is on the damn couch. In the non-causal items, the subject (holiday) cannot plausibly be taken as being responsible for the state of affairs described. However, in the causal items, the subject might be responsible for the state of affairs described. The same range of interpretations was observed for all placements of damn. The prior utterance condition (Damn. The dog is on the couch.) yielded more entire situation interpretations than the sentence-internal damn items. Overall, subject damn items yielded more subject interpretations than object damn items. However, as predicted by the hypothesis that blame would devolve on a potentially responsible agent (the culprit hypothesis), there were more subject interpretations in the causal items than in the non-causal items. The results suggest that considerable pragmatic inferencing is involved in the interpretation of expressives, consistent with a proposal that an expressive constitutes a separate speech act.

Embodied theories of cognition propose that humans use sensorimotor systems in processing language. The Action-Sentence Compatibility Effect (ACE) refers to the finding that motor responses are facilitated after comprehending sentences that imply movement in the same direction. In sign languages there is a potential conflict between sensorimotor systems and linguistic semantics: movement away from the signer is perceived as motion toward the comprehender. We examined whether perceptual processing of sign movement or verb semantics modulate the ACE. Deaf ASL signers performed a semantic judgment task while viewing signed sentences expressing toward or away motion. We found a significant congruency effect relative to the verb’s semantics rather than to the perceived motion. This result indicates that (a) the motor system is involved in the comprehension of a visual–manual language, and (b) motor simulations for sign language are modulated by verb semantics rather than by the perceived visual motion of the hands.