It has been widely demonstrated that dreaming occurs throughout human sleep. However, we once again are facing new variants of the equation “REM sleep = Dreaming.” Nielsen proposes a model that assumes covert REM processes in NREM sleep. I argue against this possibility, because dream research has shown that REM sleep is not a necessary condition for dreaming to occur.

[Nielson]

Whitehouse's focus on two causes of identity fusion (evolution and shared experiences/biology) deepens understanding of these specific topics. While we applaud his analysis, in his efforts to elaborate these two causes, he has – perhaps unavoidably – produced a narrower conceptualization of identity fusion. This is unfortunate because it undermines his stated goal of developing a more general, encompassing theory.

Davey has failed to clarify the critical evidence that could corroborate the expectancy bias hypothesis and refute preparedness theory. Such a clarification is necessary because each theory could potentially allow for multiple distal and proximal influences on selective associations. Expectancies are not the only proximal mediators. Our recent findings indicate that affective response matching may be an additional factor promoting such associations.

Empirical evidence suggests that high frequency electrographic activity is involved in active representation of meaningful entities in the cortex. Theoretical work suggests that distributed cell assemblies also represent meaningful entities. However, we are still some way from understanding how these two are related. This commentary also makes suggestions for further investigation of the neural basis of language at the level of both words and sentence planning.

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 support Pepper and Nettle's (P&N's) hypothesised adaptive responses to deprivation. However, we argue that adaptive responses to stress shift with age. Specifically, present-oriented behaviours are adaptive for young people (e.g., in terms of mating and reproduction) but costly for older people in deprived communities who would benefit from investing in grandchildren. Epigenetic mechanisms may be responsible for age-related tactical shifts.

We propose an extension to Mahr & Csibra's (M&C's) theory. For successful episodic memory formation, potentially relevant aspects of a situation need to be identified and encoded online and retained for prospective interactions. To be maximally convincing, the communicator not only has to encode not just any contextual detail, but also has to track information in relation to social partners.

We agree with Ramsey et al. regarding the need for new methods and concepts in the study of innovation, and welcome their initiative, but are concerned that their operationalization is over-reliant on subjective judgements.

Byrne & Hilbert are right that it might be an objective fact that a particular tomato is unique red, but wrong that it cannot simultaneously be yellowish-red (not only objectively, but from somebody else's point of view). Sensory categorization varies among organisms, slightly among conspecifics, and sharply across taxa. There is no question of truth or falsity concerning choice of categories, only of utility and disutility. The appropriate framework for color categories is Nominalism and Pluralistic Realism.

The discovery of a quaternary complexity limitation to mature cognitive operations raises important theoretical issues. We propose that cognitive limitations arise naturally in a complex dynamic information processing system, and consider problems such as the distinction between parallel and serial processes and the representativeness of the empirical data base used by Halford et al. to support their relational complexity scheme.

Reichle et al. specify two assumptions as being basic to E-Z Reader: Words are sequentially attended during fixations, and saccades are triggered by a cognitive event. We point out that there is little evidence for the first assumption and counterevidence for the second. Also, the labile/nonlabile stage distinction in saccade preparation seems to be contrary to current evidence. An alternative explanation of saccade onset times in reading assumes that saccades are strategically generated, independent of language processing, but are delayed on a probabilistic basis by processing difficulties.

The purpose of human cognition depends on the problem people try to solve. Defining the purpose is difficult, because people seem capable of representing problems in an infinite number of ways. The way in which the function of cognition develops needs to be central to our theories.

Mahr & Csibra (M&C) propose that episodic memory evolved to support epistemic authority in social communication. We argue for a more parsimonious interpretation whereby episodic memory subserves a broader preparatory function for both social and non-social behavior. We conclude by highlighting that functional accounts of episodic memory may need to consider the complex interrelations between self and subjective time.