Wittgenstein shifted from a picture theory of meaning to a use-based theory of meaning in his philosophical work on language. The latter picture is deeply congenial to the view that language and the use of our hands in practical activity are closely related. Wittgenstein's theory therefore offers philosophical support for Corballis's suggestion that the development of spoken language is the basis of dominance phenomena.

The commentaries on our article encourage us to believe that researchers are beginning to take seriously the goal of achieving the broad adequacy that Newell aspired to. The commentators offer useful elaborations to the criteria we suggested for the Newell Test. We agree with many of the commentators that classical connectionism is too restrictive to achieve this broad adequacy, and that other connectionist approaches are not so limited and can deal with the symbolic components of thought. All these approaches, including ACT-R, need to accept the idea that progress in science is a matter of better approximating these goals, and it is premature to be making judgments of true or false.

We propose that the primary cause of schizophrenia is a pathological extension of synaptic pruning involving local connectivity that unfolds ordinarily during adolescence. Computer simulations suggest that this pathology provides reasonable accounts of a range of symptoms in schizophrenia, and is consistent with recent postmortem and genetic studies. NMDA-receptors play a regulatory role in maintaining and/or eliminating cortical synapses, and therefore may play a pathophysiological role.

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.

We focus on the functional specificity of theta and alpha oscillations and show that theta is related to working memory, whereas alpha is related to semantic long-term memory. Recent studies, however, indicate that alpha oscillations also play an important role during short-term memory retention and retrieval. This latter finding provides support for the basic hypothesis suggested by Ruchkin et al.

Studies of neuropsychological patients are relevant to models of how long-term memories are stored. If amnesia is considered a binding deficit and not a difficulty in transferring information from short-term to long-term memory, it is unclear why context-free semantic learning is impaired. Also the model should account for the reverse temporal gradient seen in patients with semantic dementia.

Given the primate propensity to make noise, it is unclear why a manual gestural stage would have been necessary in the development of either language or right-handedness. Cortical asymmetries are present in australopithecines but become clearly human-like with the appearance of Homo about two million years ago, including Broca's cap regions. Stone tool-making is still our only empirical entry into past cognitive processes.

An action-oriented theory of embodied memory is favorable for many reasons, but it will not provide a quick yet clean solution to the grounding problem in the way Glenberg (1997t) envisages. Although structural mapping via analogical representations may be an adequate mechanism of cognitive representation, it will not suffice to explain representation as such.

As the number of computational models of eye-movement control in reading increases, so too will their coverage and complexity. This will make their comparison and testing increasingly challenging. We argue here that there is a need to develop a methodology for constructing and evaluating such models, and outline aspects of a possible methodology.

N-methyl-d-aspartate receptor (NMDAR) dysfunction plays a crucial role in schizophrenia, leading to impairments in cognitive coordination. NMDAR agonists (e.g., glycine) ameliorate negative and cognitive symptoms, consistent with NMDAR models. However, not all types of cognitive coordination use NMDAR. Further, not all aspects of cognitive coordination are impaired in schizophrenia, suggesting the need for specificity in applying the cognitive coordination construct.

Neurophysiological investigations of the past two decades have consistently demonstrated a deficit in sensory gating associated with schizophrenia. Phillips & Silverstein interpret this impairment as being consistent with cognitive coordination dysfunction. However, the physiological mechanisms that underlie sensory gating have not been shown to involve gamma-band oscillations or NMDA-receptors, both of which are critical neural elements in the cognitive coordination model.

Ruchkin et al. make a strong claim about the neural substrates of active information. Some qualifications on that conclusion are: (1) Long-term memories and neural substrates activated for perception of information are not the same thing; (2) humans are capable of retaining novel information in working memory, which is not long-term memory; (3) the content of working memory, a dynamically bound representation, is a quantity above and beyond the long-term memories activated, or the activity in perceptual substrates.

The target article by Corballis presents an interesting and novel theoretical perspective on the evolution of language, speech, and handedness. There are two specific aspects of the article that will be addressed in this commentary: (a) the link between Broca's area and gestural communication in chimpanzees, and (b) the issue of population-level handedness in great apes, notably chimpanzees.

This commentary examines Glenberg's characterization of “suppression” in light of negative priming and related phenomena. After offering a radically different slant on suppression, an attempt is made to weave this alternative version into Glenberg's provocative discussion of embodied memories.

It is argued here that a critical prediction of the E-Z Reader model is that experimental manipulations that disrupt early encoding of visual and orthographic features of the fixated word without affecting subsequent lexical processing should influence the processing difficulty of the fixated word without producing any processing effect on the next word. This prediction is explained and illustrated.

Working-memory retention as activated long-term memory fails to capture orchestrated processing and storage, the hallmark of the concept of working memory. The event-related potential (ERP) data are compatible with working memory as a mental workspace that holds and manipulates information on line, which is distinct from long-term memory, and deals with the products of activated traces from stored knowledge.

Schizophrenics exhibit a deficit in theory of mind (ToM), but an intact theory of biology (ToB). One explanation is that ToM relies on an independent module that is selectively damaged. Phillips & Silverstein's analyses suggest an alternative: ToM requires the type of coordination that is impaired in schizophrenia, whereas ToB is spared because this type of coordination is not involved.

Although the E-Z Reader model accounts well for eye-tracking data, it will be judged by new predictions and consistency with evidence from brain imaging methodologies. The stage architecture proposed for lexical access seems somewhat arbitrary and calculated timings are conservatively slow. There are certain effects in the literature that seem incompatible with the model.

The evolutionary scenario described in this target article parallels developmental patterns observed in human infants. Early vocalizations are largely expressive, manual control develops more rapidly than intentional vocal articulation, and vocal and manual activity are linked. In ontogenetic development, language is strongly rooted in bodily action and gesture.

Arthur M. Glenberg omits discussion of motivation and this leads him to an underestimation of the part played by pleasure and pain and desire and fear in both the clamping and the updating of percepts. This commentary aims at rectifying this omission, showing that mutual correction plays an important role.