Dienes & Perner propose a theory of implicit and explicit knowledge that is not entirely complete. It does not address many of the empirical issues, nor does it explain the difference between implicit and explicit learning. It does, however, provide a possible unified explanation, as opposed to the more binary theories like the systems and the processing theories of implicit and explicit memory. Furthermore, it is consistent with a theory in which implicit learning is viewed as based on the mechanisms of the cognitive architecture, and explicit learning as strategies that exploit these mechanisms.

Empathy is a developmental process whereby individuals come to understand the emotional states of others. While the exact nature of this process remains unknown, PAM's utility is that it establishes empathy along a continuum of behavior ranging from emotional contagion to cognitive forms, a very useful distinction for understanding the phylogeny and ontogeny of this important process. The model will undoubtedly fuel future research, especially from comparative domains where data are most problematic.

It is suggested (1) that motivation must not be overlooked, (2) that most social imitation does not involve novel behaviors, and (3) that newborn babies do imitate.

Research only alluded to by Preston & de Waal (P&deW) indicates the disproportionate involvement of some brain regions in the perception and experience of certain emotions. This suggests that the neural substrate of primitive emotional contagion has some emotion-specific aspects, even if cognitively sophisticated forms of empathy do not. Goals for future research include determining the ways in which empathy is emotion-specific and dependent on overt or covert perception.

Rips et al. appear to discuss, and then dismiss with counterexamples, the brain-based theory of mathematical cognition given in Lakoff and Núñez (2000). Instead, they present another theory of their own that they correctly dismiss. Our theory is based on neural learning. Rips et al. misrepresent our theory as being directly about real-world experience and mappings directly from that experience.

Although humans are endowed with domain-specific constraints for acquiring informal biology, its construction requires considerable experience with living things and their cultural representations. Less experienced adults may not know what constitutes generic species, and young children may rely on personification rather than category-based inference. Atran's postulate of the living-kind module that promptly produces universal folk taxonomy does not seem tenable.

Wynn shows that intentionally standardized artifacts (handaxes) provide evidence of the ability to conceptualize form (symmetry). However, such conceptual ability is not sufficient for the actual production of these forms. Stone knapping is a concrete skill that is acquired in the real world. Appreciation of its perceptual-motor foundations and the broader issues surrounding skill acquisition may lead to further important insights into human cognitive evolution.

The analogy between the rules that subtend ventriloquism and bimodal neurons responding suggests a possible neural mechanism for audiovisual interactions in spatial scene analysis. Perinatal data, such as those on synesthesia, sensory deprivation, and sensory surstimulation, as well as neuroanatomical evidence for transitory intersensory connections in the brain support the view that audition and vision are bound together at birth.

Byrne & Russon propose that priming can account for the imitation of simple actions, but they fail to explain how the behavior of another can prime the observer's own behavior. They also propose that imitation of complex skills requires a sequence of acts tied together by a program, but they fail to rule out the role of trial-and-error learning and perceptual/motivational mechanisms in such task acquisition.

This commentary focuses on the “olfactory cortices–hippocampal formation” axis, proposed by Aboitiz et al. to be that network which allowed the first mammals to create elaborate representations of space. I argue here that this neural axis can be extended to a triangle of structures which also includes the orbital cortex.

Four extensions of Carruthers’ arguments are given. (1) Specifics of the Vygotskyan tradition can enhance his claims. (2) Linguistic relativity might be seen as variation in how logical form (LF) and phonetic form (PF)serve working memory. (3) Language aids intermodular thinking because it makes representations maximally visible. (4) Language for intermodular thinking is not hardwired but opportunistic.

Perception and cognition can be understood either as conscious experience, thought, and behaviour or as bodily functions executed at the level of information processing. Whether or not they are cognitively penetrable depends on the level referred to. Selective attention is the mechanism by which cognition affects perception, theory influences observation and observational reports, culture biases experience, and current knowledge determines what inferences are made. Seeing must be distinguished from seeing as.

We address two major limitations of Schyns et al. First, we clarify their concept of “features” by postulating several levels for processing. The composition of the feature set at each level determines the set at the next higher level, following simple structural guidelines. Second, we show that our proposed framework reconciles feature-creation and fixed-feature approaches.

With regard to social-cognitive deficits in autism and psychosis, Crespi & Badcock's (C&B's) theory does not incorporate the developmental context of the disorders. We propose that there is significant overlap in social-cognitive impairments, but that the exact manifestation of social-cognitive deficits is highly dependent on the dynamics of cognitive development and hence different in autism as compared to psychosis.

Medical education provides many examples of the development of functional features, but as a response to deliberate instruction. These features require so much specificity and context sensitivity that they seem likely to require the development of new categories of appearances rather than just reweighting old features. A suggested implication is that feature development may help to explain the problematic noticing of features in diagnosis.

Blair makes a strong case that fluid cognition and psychometric g are not identical constructs. However, he fails to mention the development of the prefrontal cortex, which likely makes the Gf–g distinction different in children than in adults.1 He also incorrectly states that current IQ tests do not measure Gf; we discuss several recent instruments that measure Gf quite well.

Is there any ecological purpose in assuming that perception for action exists only through a global array of energy? Unlike Stoffregen & Bardy, who assume that behavior consists of movements, we would argue that behavior consists of a stable coupling between perception and action achieved through experience in an adaptive context. Determining target position in an aiming manual task and temporal control of impact movement illustrate that patterns of energy used for action are task-dependent.

E-Z Reader 7 is a processing model of eye-movement control. One constraint imposed on the model is that high-level cognitive processes do not influence eye movements unless normal reading processes are disturbed. I suggest that this constraint is unnecessary, and that the model provides a sensible architecture for explaining how both low- and high-level processes influence eye movements.

This commentary questions the applicability of the Newell Test for evaluating the utility of connectionism. Rather than being a specific theory of cognition (because connectionism can be used to model nativist, behaviorist, or constructivist theories), connectionism, we argue, offers researchers a collection of computational and conceptual tools that are particularly useful for investigating and rendering specific fundamental issues of human development. These benefits of connectionism are not well captured by evaluating it against Newell's criteria for a unified theory of cognition.

Although an excellent review, the target article displays a bias in favor of reciprocity-based explanations and against alternatives. Tolerated scrounging is more subtle and pervasive than portrayed here. Costly signaling need not be limited to public displays and generalized sharing. The theoretical basis for extensive sharing and other forms of collective action remains unresolved, and standard reciprocity-based explanations are insufficient.