Imitation research has been hindered by (1) overly molecular analyses of behaviour that ignore hierarchical structure, and (2) attempts to disqualify observational evidence. Program-level imitation is one of a range of cognitive skills for scheduling efficient novel behaviour, in particular, enabling an individual to purloin the organization of another's behaviour for its own. To do so, the individual must perceive the underlying hierarchical schedule of the fluid action it observes and must understand the local functions of subroutines within the overall goal-directed process. Action-level imitation, copying strings of actions linearly without any such understanding, is less valuable for acquiring complex behaviour and may often have other, social functions. At present, we lack a mechanistic understanding of the abilities underlying program-level imitation that make it possible for the underlying structure of complex actions to be dissected visually and recreated in behaviour.

The cultural group selection (CGS) approach provides a compelling explanation for recent changes in human societies, but has trouble explaining why our ancestors, rather than any other great ape, evolved into a hyper-cooperative niche. The cooperative breeding hypothesis can plug this gap and thus complement CGS, because recent comparative evidence suggests that it promoted proactive prosociality, social transmission, and communication in Pleistocene hominins.

Gilead et al. raise some fascinating issues about representational substrates and structures in the predictive brain. This commentary drills down on a core theme in their arguments; namely, the structure of models that generate predictions. In particular, it highlights their factorial nature – both in terms of deep hierarchies over levels of abstraction and, crucially, time – and how this underwrites agency.

Roger Shepard's proposals and supporting experiments concerning evolutionary internalized regularities have been very influential in the study of vision and in other areas of psychology and cognitive science. This paper examines issues concerning the need, nature, explanatory role, and justification for postulating such internalized constraints. In particular, I seek further clarification from Shepard on how best to understand his claim that principles of kinematic geometry underlie phenomena of motion perception.

My primary focus is on the ecological validity of Shepard's kinematic constraint in the context of ordinary motion perception. First, I explore the analogy Shepard draws between internalized circadian rhythms and the supposed internalization of kinematic geometry. Next, questions are raised about how to interpret and justify applying results from his own and others' experimental studies of apparent motion to more everyday cases of motion perception in richer environments. Finally, some difficulties with Shepard's account of the evolutionary development of his kinematic constraint are considered.

I defend the claim that in psychological theories concerned with theoretical or practical rationality there is a constitutive relation between normative and descriptive theories: Normative theories provide idealized descriptive accounts of rational agents. However, we need to resist the temptation to collapse descriptive theories with any specific normative theory. I show how a partial separation is possible.

Cimpian & Salomon (C&S) propose that the inherence heuristic, a tendency to explain the behavior and other properties of things in terms of their intrinsic characteristics, precedes and explains “essentialist thinking” about natural kinds. This commentary reviews evidence that it is rather essentialism (or something like it) that precedes the assumption of inherence, and suggests that essentialism can do without the inherence heuristic altogether.

According to Davey, generalized expectancy biases cause fearrelevant behavior and may complement Seligman's biological preparedness model. Expectancy biases do not explain the preparedness phenomenon, because such cognitive (or covert behavioral) processes are themselves controlled by social and other environmentally based contingencies. Davey's own examination of the importance of cross-cultural factors can show the relationship between FR stimuli and behavior without needing cognitive agency to explain the behavioral phenomenon.

Images of mind marks a new era in human cognitive neuroscience. Despite the difficult conceptual problems associated with using group-averaged data and paired subtractions, human PET images converge well with existing data from other areas of cognitive neuroscience while opening up new theoretical and experimental possibilities. However, greater attention to individual differences might prove necessary in the study of culturally driven adaptations such as literacy.

Neurally inspired models of human cognition exude explanatory power without necessarily making predictions that can be verified behaviorally. This is the case for Tsuda's dynamic model. It is suggested that a simpler principle based on the nonlinear dynamic interaction between modules based on control of chaos, can achieve a similar theoretical goal in a cognitively verifiable way.

Defending first-person introspective access to own mental states, we argue against Carruthers' claim of mindreading being prior to meta-cognition and for a fundamental difference between how we understand our own and others' mental states. We conclude that a model based on one mechanism but involving two different kinds of access for self and other is sufficient and more consistent with the evidence.

Heyes's attempt to reinterpret research on primate cognition from the standpoint of radical behaviorism is strong on dialogue and debate but weak on evidence. Recent evidence concerning self-recognition, for example, shows that her arguments about differential recovery from anesthetization and species differences in face touching as alternative accounts of the behavior of primates in the presence of mirrors) are invalid.

Because, as Palmer shows, the only kinds of differences that can be detected are differences in relational structure, and relational structure is precisely what is preserved by isomorphism, his own arguments can be used to expose the incoherent motivation behind the traditional idea of “intrinsic qualities” of experience.

Applying the framework proposed by Jeffery et al. to nonhuman primates moving in multilayer arboreal and terrestrial environments, we see that these animals must generate a mosaic of many bicoded spaces in order to move efficiently and safely through their habitat. Terrestrial light detection and ranging (LiDAR) technology and three-dimensional modelling of canopy movement may permit testing of Jeffery et al.'s framework in natural environments.

The driving force in the evolution of language and the human mind was the advantage gained in courtship by efficient communicators. Ontogeny recapitulating phylogeny may offer an alternative to Donald's picture of the relative origins of language and mimesis. Very recent evidence is pertinent to dating the origin of language.

Motor processes cannot be modeled by a single (unified) model. Instead, a number of models at different levels of description are needed. The concepts of control and control variable only make sense at the functional level. A clear distinction must be made between external models and internal models. General Systems Theory provides the framework for a proper treatment of these issues.

Pickering & Garrod's (P&G's) mechanistic account of dialogue assumes that linguistic alignment between interlocutors takes place automatically, without using cognitive resources. However, even the most basic processes of speech perception depend on resource use. The lack of invariant mapping between input patterns and interpretations in dialogue, as in speech perception, may require controlled, rather than automatic, processing.

Richerson et al. argue that relatively large cultural FST values provide evidence for group structure and therefore scope for group selection. However, recent research on spatial patterns of cultural variation demonstrates that, as in the genetic case, apparent group structure can be a consequence of geographic clines, not group barriers. Such a pattern limits the scope for cultural group selection.