Did protolanguage users use discrete words that referred to objects, actions, locations, etc., and then, at some point, combine them; or on the contrary did they have words that globally indexed whole semantic complexes, and then come to divide them? Our answer is: early humans were forming language units consisting of global and discrete dimensions of semiosis in dynamic opposition. These units of thinking-for-speaking, or ‘growth points’ (GPs) were, jointly, analog imagery (visuo-spatio-motoric) and categorically-contrastive (-emic) linguistic encodings. This discrete-global duality (...) was a new mode of embodied cognition that enabled thinking and acting in new ways: the dawn of protolanguage. Where did this mode of cognition come from? We have some suggestions based on the hypothesis that gestures gained the power to orchestrate actions, manual and vocal, with significances other than those of the actions themselves, giving rise to cognition framed in the proposed dual terms. Note, however, our proposal is not one of the ‘gesture-first’ theories of language origins. Such theories predict what did not evolve: a language of pantomime; rather than what did evolve: an integrated system of synchronized gestures and spoken forms. GP theory is an account of the cognition underlying such an integrated system. A scenario for the evolutionary selection of this cognitive mode is ‘Mead’s Loop’, a model in which one’s cognition is enriched by one’s own gestures, insofar as they are objects in social interactions. (shrink)

Early humans formed language units consisting of global and discrete dimensions of semiosis in dynamic opposition, or ‘growth points.’ At some point, gestures gained the power to orchestrate actions, manual and vocal, with significances other than those of the actions themselves, giving rise to cognition framed in dual terms. However, our proposal emphasizes natural selection of joint gesture-speech, not ‘gesture-first’ in language origin.

Cooper et al. (this issue) develop an interactive activation model of spatial and imitative compatibilities that simulates the key results from Catmur and Heyes (2011) and thus conclude that both compatibilities are mediated by the same processes since their single model can predict all the results. Although the model is impressive, the conclusions are premature because they are based on an incomplete review of the relevant literature and because the model includes some questionable assumptions. Moreover, a competing model (Scheutz & (...) Bertenthal, 2012) is introduced that suggests the two compatibilities are not mediated by the same processes. We propose that more research is necessary before concluding that spatial and imitative compatibilities are mediated by the same processes. (shrink)

Three challenges to the sufficiency of the associative account for explaining the development of mirror mechanisms are discussed: Genetic predispositions interact with associative learning, infants show predispositions to imitate human as opposed to nonhuman actions, and early and later learning involve different mechanisms. Legitimate objections to an extreme nativist account are raised, but the proposed solution is equally problematic.

We present two challenges to the fearful ape hypothesis: (1) biobehavioral synchrony precedes and moderates the effects of fear on cooperative care, and (2) cooperative care emerges in a more bidirectional manner than Grossmann acknowledges. We present evidence demonstrating how dyadic differences in co-regulation and individual differences in infants' reactivity shape caregivers' responses to infant affect.

We question the generalizability of Glover's model because it fails to distinguish between different forms of planning. The highly controlled experimental situations on which this model is based, do not reflect some important factors that contribute to planning. We discuss several classes of action that seem to imply distinct planning mechanisms, questioning Glover's postulation of a single “planning system.”.

The empirical support for the shared circuits model (SCM) is mixed. We review recent results from our own lab and others supporting a central claim of SCM that mirroring occurs at multiple levels of representation. By contrast, the model is silent as to why human infants are capable of showing imitative behaviours mediated by a mirror system. This limitation is a problem with formal models that address neither the neural correlates nor the behavioural evidence directly.

Although Arbib's extension of the mirror-system hypothesis neatly sidesteps one problem with the “gesture-first” theory of language origins, it overlooks the importance of gestures that occur in current-day human linguistic performance, and this lands it with another problem. We argue that, instead of gesture-first, a system of combined vocalization and gestures would have been a more natural evolutionary unit.