We propose that Bloom's focus on cognitive factors involved in word learning still lacks a broader perspective. We emphasize the crucial relevance of working memory in learning elements of language. Specifically, we demonstrate through our data that in impaired populations knowledge of some linguistic elements can be dissociated according to the subcomponent of working memory (visual or verbal) involved in a task. Further, although Bloom's concentration on theory of mind as a precondition for word learning is certainly correct, theory of mind being a necessary condition does not make it a sufficient one. On the basis of our studies we point out the importance of a theory of mind related goal preference in acquiring spatial language. In general, we claim that more specific cognitive preferences and constraints should be outlined in detail for the preconditions of acquiring linguistic elements.

Brain parts can scale independently of the whole brain, and an example is given to point out that the authors underestimate variation that can exist in brains of equal size.

Computational models of learning provide an alternative technique for identifying the number and type of chunks used by a subject in a specific task. Results from applying CHREST to chess expertise support the theoretical framework of Cowan and a limit in visual short-term memory capacity of 3–4 looms. An application to learning from diagrams illustrates different identifiable forms of chunk.

To account for category-specific semantic deficits, Humphreys and Forde propose to fractionate semantic memory into multiple sensory and functional knowledge stores. There are reasons to doubt the empirical productivity of this proposal, unless theoretically motivated principles of distinguishing and weighting the different kinds of object knowledge can be spelled out in detail.

Hommel et al. propose that high-level perception and action planning share a common representational domain, which facilitates the control of intentional actions. On the surface, this point of view appears quite different from an alternative account that suggests that “action” and “perception” are functionally and neurologically dissociable processes. But it is difficult to reconcile these apparently different perspectives, because Hommel et al. do not clearly specify what they mean by “perception” and “action planning.” With respect to the visual control of action, a distinction must be made between conscious visual perception and unconscious visuomotor processing. Hommel et al. must also distinguish between the what and how aspects of action planning, that is, planning what to do versus planning how to do it.

Shepard has challenged psychologists to identify nonarbitrary principles of mind upon which to build a more explanatory and general cognitive science. I suggest that such nonarbitrary principles may fruitfully be sought not only in the laws of physics and mathematics, but also in the logical entailments of different categories of representation. In the example offered here, conceptualizing mental events as indexical with respect to the events they represent enables one to account parsimoniously for a wide range of empirical psychological phenomena. [Shepard]

Although many aspects of human cognition are likely to be “spandrels” passively affiliated with the primary impetus for hominid brain expansion during the Plio-Pleistocene, that expansion was most likely generated and maintained not by “housekeeping” functions but by improved capacities of reproductive success, especially survivorship.

We note two important problems in the Theory of Event Coding. First, because the representational format of features and events is unspecified, the theory is difficult to test. Second, the theory lacks a mechanism for the integration of features into an event code when the features are shared by different events. Possible ways of solving these problems are suggested.

The perceptual circularity demonstrated by R. Shepard with respect to hue turns out to be a sphericity of color perception based on color excitation vectors of neuronal level. The spherical color model implicitly contains information concerning generalization under color learning. Subjective color differences are “computed” in neuronal nets being represented by amplitudes of evoked potentials triggered by color change. [Shepard]

Measures of retrieval speed for recently presented events show a sharp dichotomy between representations in focal attention and representations that are recently processed but no longer attended. When information is presented over time, retrieval measures show that focal attention and rapid privileged access is limited to the most recently processed unit or chunk, not the last 3–5 chunks that Cowan estimates from various recall procedures.

Bloom's book can be viewed as a long argument for an anti-Whorfian conclusion. According to Bloom, word learning is usually a process of mapping new words to pre-existing concepts. But an exception to this generalization – the learning of words from linguistic context – poses a problem for Bloom's anti-Whorfian argument.

The HIT model comes close to a view suggested by Donald Hebb, that cognitive representations are organized as distributed neuron webs, cell assemblies, whose components are mutually connected and whose internal connections provide continuous information exchange among sub-components of the representation. Two questions are asked related to (1) the organization of internal connections of a concept representation and (2) the conditions under which information exchange between components are assumed in the HIT model.

Cowan postulates that the capacity of short-term memory is limited to the number of items to which attention can be simultaneously directed. Unfortunately, he endows attention with unexplained properties, such as being able to locate the most recent inputs to short-term memory, so his theory does little more than restate the data.

One of the mammalian groups absent from the Finlay et al. study is cetaceans (dolphins, whales, and porpoises). Inclusion of cetaceans would be useful for assessing the generalizability of the authors' conclusions. Recent findings suggest dolphins may differ from the general pattern observed by Finlay et al. I encourage Finlay and her colleagues to include developmental neurobiological data on cetaceans, when available.

We offer additional points that support a distributed semantic memory: (1) the activation of representations that are modality-specific; (2) patients with inferotemporal lesions fail to activate visual object representations in semantic tasks, although normal subjects do; (3) direct activation of action systems from pictorial information, but not from words; (4) patients who demonstrate superiority with abstract words fail to access perceptual representations.

Shepard promotes the important view that evolution constructs cognitive mechanisms that work with internalized aspects of the structure of their environment. But what can this internalization mean? We contrast three views: Shepard's mirrors reflecting the world, Brunswik's lens inferring the world, and Simon's scissors exploiting the world. We argue that Simon's scissors metaphor is more appropriate for higher-order cognitive mechanisms and ask how far it can also be applied to perceptual tasks. [Barlow; Kubovy & Epstein; Shepard]

The Theory of Event Coding deals with brief events but has implications for longer, complex events, particularly goal-directed activities. Two of the theory's central claims are consistent with or assumed by theories of complex events. However, the claim that event codes arise from the rapid activation and integration of features presents challenges for scaling up to larger events.

We propose that in addition to children's requests for word names being a reflection of an understanding of the referential nature of words, they may also be requests for adult's teaching. These possible requests for teaching among toddlers, along with other indications, suggest that teaching may be a natural cognition that may be related to the development of theory of mind.

This commentary questions whether the category properties of an object can be determined independent of the experience of the categorizer. Expertise studies have shown that the judged properties of an object can differ from expert to novice and from expert to expert. The expertise findings indicate that object properties exist not only in the world, but in the mind of the categorizer.

The Kubovy-Epstein proposal for the formalization of the relation between kinematic geometry and perception of motion has formal problems in itself. Motion phenomena are inadequately captured by the relational structures and the notion of isomorphism taken over from measurement theory. [Kubovy & Epstein]