According to Keven & Akins (K&A), infant orofacial gestures may not reflect imitative responses. Here, we emphasise that these actions nonetheless represent a significant feature of the infant's early sensorimotor experience, and therefore may play a key role in the development of imitative capacities. We discuss how the ideas proposed in the target article could contribute substantially to experiential accounts of imitation.

Metaphors and models involve correspondences between events in separate domains. They differ in the form and precision of how the correspondences are expressed. Examples include correspondences between phylogenic and ontogenic selection, and wave and particle metaphors of the mathematics of quantum physics. An implication is that the target article's metaphors of resistance to change may have heuristic advantages over those of momentum.

Several commentators argue that there remains a gap between cerebellar long-term depression (LTD) studied in vitro and cerebellar functions such as motor learning. Recent developments in a gene-targeting technique for producing mutant mice defective in particular gene products has opened a new era for the study of synaptic plasticity and learning. There are three mutants in which cerebellar LTD are clearly deficient in vitro. Two of these mice show clear impairment in the conditioned eyeblink response, a paradigm known to involve the cerebellum. In contrast, one mutant with apparently normal cerebellar LTD showed no impairment in the conditioned eyeblink response. These new lines of evidence support the view that cerebellar LTD is a cellular basis for discrete motor learning.

We support Ackermann et al.'s proposal that the cortico-basal ganglia circuits may play essential roles in the evolution of spoken language. Here we discuss further evidence indicating that the cortico-basal ganglia circuits may contribute to various aspects of spoken language including planning, learning, and controlling of speech in adulthood.

In offering a detailed view of putative steps towards the emergence of language from a cognitive standpoint, Michael Arbib is also introducing an evolutionary framework that can be used as a useful tool to confront other viewpoints on language evolution, including hypotheses that emphasize possible alternatives to suggestions that language could not have emerged from an earlier primate vocal communication system.

There are three concerns regarding Rachlin's altruism model. First, proximal causal mechanisms such as those identified by cognitive neuroscientists and behavioral neuropharmacologists are not emphasized. Second, there is a lack of clear testable hypotheses. And third, extreme forms of altruism are emphasized rather than common forms. We focus on an overarching theme – proximal mechanisms of individual differences in altruism.

Carruthers’ argument depends on viewing logical form as a linguistic level. But logical form is typically viewed as underpinning general purpose inference, and hence as having no particular connection to language processing. If logical form is tied directly to language, two problems arise: a logical problem concerning language acquisition and the empirical problem that aphasics appear capable of cross-modular reasoning.

We are sympathetic with Bentley et al.’s attempt to encompass the wisdom of crowds in a generative model, but posit that a successful attempt at using big data will include more sensitive measurements, more varied sources of information, and will also build from the indirect information available through technology, from ancillary technical features to data from brain–computer interfaces.

the dynamic developmental theory of attention-deficit/hyperactivity disorder (adhd) proposes that hypodopaminergic functioning results in anomalous delay-of-reinforcement gradients in adhd, which in turn might account for many of the observed behavioral and cognitive characteristics. however, hyperdopaminergic functioning might also impair mnemonic representation of codes for spatial, motoric, and reward information and contribute to the purported shorter delay gradients in adhd.

We focus on two components of Page's argument in favour of localist representations in connectionist networks: First, we take issue with the claim that localist representations can give rise to generalisation and show that whenever generalisation occurs, distributed representations are involved. Second, we counter the alleged shortcomings of distributed representations and show that their properties are preferable to those of localist approaches.

Christiansen & Chater (C&C) make two related and somewhat contradictory claims, namely that the ever abstract language representations built during Chunk-and-Pass processing allow for ever greater interference from extra-linguistic information, and that it is nevertheless the language system that re-codes incoming information into abstract representations. I analyse these claims and discuss evidence suggesting that Gestalt-like representations hijack Chunk-and-Pass processing.

Koriat & Goldsmith (1996t) present two different programs for memory research. Different though they are on the methodological level, on the substantive level the two programs are based on the same view, according to which memory consists of represented information that is permanently stored in the mind (or brain). This view is, I think, wrong. One can support the methodological pluralism Koriat & Goldsmith advocate, but on the substantive level pluralism is not admissible.