This commentary focuses on Findlay & Walker's model and more specifically, on its underestimation of the role of cognitive processes in eye movement control during complex activities such as text scanning. In particular, the issue of the complexity of the subject's task/behavior is discussed to stress the importance of the link between selection for perceptual processing on the one hand, and the selection of a target for a saccade, on the other. Future models will have to account for the fact that the goal of any saccade is to bring the eyes to a relevant object and that the selection of this saccade target is closely related to object recognition.

A distinction is made between structural and semantic knowledge, focusing on the possible influences of the latter. To the extent that early vision may be influenced by object-identity, it would seem necessary to evoke compiled transducers to explain such an influence. Compiled transducers may furnish a way in which vision can be and is penetrated.

We discuss the role of short-term auditory verbal storage within a working memory system. Data from single case studies of patients with left parietal lesions and selective impairment of memory span are discussed in order to address the question of the functions of short-term memory in language processing. The backup resource of auditory verbal short-term memory is required for those tasks that necessitate backtracking in order to integrate a verbal message within a developing central cognitive representation.

We critique five points that impede the target article's far-reaching efforts toward formulating a neurobiological theory of language. Neurolinguistics amounts to no more than neurology in linguistics in this account, because it assumes “perceptual representational isomorphism,” processing autonomy and “meaning,” thereby aiming primarily at justifying modular concepts in terms of associative principles.

The experimental results reported in Clahsen's target article clearly distinguish regular from irregular processes and suggest a basic difference between items that are productively formed and items which are stored in the lexicon. However, these results do not directly implicate any particular combinatory operation (such as affixation), nor do they distinguish inflectional items from other productive formations.

The implicit-explicit distinction is applied to knowledge representations. Knowledge is taken to be an attitude towards a proposition which is true. The proposition itself predicates a property to some entity. A number of ways in which knowledge can be implicit or explicit emerge. If a higher aspect is known explicitly then each lower one must also be known explicitly. This partial hierarchy reduces the number of ways in which knowledge can be explicit. In the most important type of implicit knowledge, representations merely reflect the property of objects or events without predicating them of any particular entity. The clearest cases of explicit knowledge of a fact are representations of one's own attitude of knowing that fact. These distinctions are discussed in their relationship to similar distinctions such as procedural-declarative, conscious-unconscious, verbalizable-nonverbalizable, direct-indirect tests, and automatic-voluntary control. This is followed by an outline of how these distinctions can be used to integrate and relate the often divergent uses of the implicit-explicit distinction in different research areas. We illustrate this for visual perception, memory, cognitive development, and artificial grammar learning.

The distinction between regular and irregular morphology is not clear-cut enough to suggest two distinct modular structures. Instead, regularity is tied directly to the type frequency of a pattern. Evidence from experiments as well as from naturally occurring sound change suggests that even regular forms have lexical storage. Finally, the development trajectory entailed by the dual-processing model is much more complex than that entailed by associative network models.

The Findlay & Walker target article emphasizes the role of the target-nonspecific “fixate” system while downplaying the role of the target-specific “move” system in determining saccade latency. We agree that disengagement of the fixate system is responsible for the target-nonspecific latency reduction associated with the gap effect. However, high target predictability and extensive training at a target location can also result in latency reductions, the culmination of this being express saccades. The target-specificity associated with the latter forms of latency reduction implicate a mechanism involving the move system. Recently discovered neurophysiological correlates underlying these behavioural phenomena reside in the superior colliculus.

Many neuroscientists and philosophers endorse a view about the explanatory reach of neuroscience (which we will call the neuron doctrine) to the effect that the framework for understanding the mind will be developed by neuroscience; or, as we will put it, that a successful theory of the mind will be solely neuroscientific. It is a consequence of this view that the sciences of the mind that cannot be expressed by means of neuroscientific concepts alone count as indirect sciences that will be discarded as neuroscience matures. This consequence is what makes the doctrine substantive, indeed, radical. We ask, first, what the neuron doctrine means and, second, whether it is true. In answer to the first question, we distinguish two versions of the doctrine. One version, the trivial neuron doctrine, turns out to be uncontroversial but unsubstantive because it fails to have the consequence that the nonneuroscientific sciences of the mind will eventually be discarded. A second version, the radical neuron doctrine, does have this consequence, but, unlike the first doctrine, is highly controversial. We argue that the neuron doctrine appears to be both substantive and uncontroversial only as a result of a conflation of these two versions. We then consider whether the radical doctrine is true. We present and evaluate three arguments for it, based either on general scientific and philosophical considerations or on the details of neuroscience itself, arguing that all three fail. We conclude that the evidence fails to support the radical neuron doctrine.

Caplan & Waters's arguments for separate working memory subsystems for “interpretive” and “post-interpretive” comprehension processes do not have a solid empirical basis. The likely involvement of a separate phonological loop makes their memory-load data irrelevant to theory evaluation, and the lack of statistical power from nonoptimal experimental designs and analyses unfairly reduces the chances of detecting the relevant interactions.

The target article claimed that although visual apprehension involves all of general cognition, a significant component of vision (referred to as early vision) works independently of cognition and yet is able to provide a surprisingly high level interpretation of visual inputs, roughly up to identifying general shape-classes. The commentators were largely sympathetic, but frequently disagreed on how to draw the boundary, on exactly what early vision delivers, on the role that attention plays, and on how to interpret the neurophysiological data showing top-down effects. A significant number simply asserted that they were not willing to accept any distinction between vision and cognition, and a surprising number even felt that we could never tell for sure, so why bother? Among the topics covered was the relation of cognition and consciousness, the relation of early vision to other modules such as face recognition and language, and the role of natural constraints.

Within the Hebbian paradigm the mechanism for integrating cell assemblies oscillating with different frequencies remains unclear. We hypothesize that such an integration may occur in cortical “interaction foci” that unite synchronously oscillated assemblies through hard-wired connections, synthesizing the information from various functional systems of the brain.

A biological neuroscientific theory must acknowledge that the function of a neurological system is to produce behaviors that promote survival. Thus, unlike what Gold & Stoljar claim, function and behavior are the province of neurobiology and cannot be relegated to the field of psychological phenomena, which would then trivialize the radical doctrine if accepted. One possible advantage of adopting such a (correctly revised) radical doctrine is that it might ultimately produce a successful, evolutionarily based, theory of mind.

Clahsen shows that “combinatorial” inflection is processed differently from “irregular” inflection. However, combinatorially regular affixes need not coincide with “class-default” affixes, that is, affixes shared by more than one inflection class and all of whose rivals are peculiar to one class. This creates a tension that may help to explain the persistence of inflection class systems.

The posterior parietal cortex and frontal eye field contain maps of visual salience on which the decision to choose a saccade may be based. However, an averaging express saccade is not represented by a victorious unimodal representation in the superior colliculus. Normalization as described by Findlay & Walker is not necessary for the generation of saccades.

Pulvermüller's work in extending Hebb's theory into the realm of language is exciting. However, we feel that what he characterizes as a single cell assembly is actually a set of cooperating cell assemblies that form parts of larger cognitive structures. These larger structures account more easily for a variety of phenomena, including the psycholinguistic.

By utilizing new information from both clinical and experimental (lesion, electrophysiological, and gene-activation) studies with animals, the anatomy underlying anterograde amnesia has been reformulated. The distinction between temporal lobe and diencephalic amnesia is of limited value in that a common feature of anterograde amnesia is damage to part of an “extended hippocampal system” comprising the hippocampus, the fornix, the mamillary bodies, and the anterior thalamic nuclei. This view, which can be traced back to Delay and Brion (1969), differs from other recent models in placing critical importance on the efferents from the hippocampus via the fornix to the diencephalon. These are necessary for the encoding and, hence, the effective subsequent recall of episodic memory. An additional feature of this hippocampal–anterior thalamic axis is the presence of projections back from the diencephalon to the temporal cortex and hippocampus that also support episodic memory. In contrast, this hippocampal system is not required for tests of item recognition that primarily tax familiarity judgements. Familiarity judgements reflect an independent process that depends on a distinct system involving the perirhinal cortex of the temporal lobe and the medial dorsal nucleus of the thalamus. In the large majority of amnesic cases both the hippocampal–anterior thalamic and the perirhinal–medial dorsal thalamic systems are compromised, leading to severe deficits in both recall and recognition.

Caplan & Waters propose a dedicated linguistic working memory to handle “interpretive” language comprehension, but there are data suggesting that more general working memory capacity can predict syntactic comprehension difficulty, and their claims depend on the existence of a principled distinction between “interpretive” and “post-interpretive” processes, which seems unlikely. Other conceptions of the source of individual differences also deserve consideration, as more flexible explanations of the phenomena.

Aggleton & Brown argue that the function of the hippocampus and perirhinal cortex can be dissociated along a spatial/nonspatial dimension. They further suggest that this division corresponds to a distinction between episodic and recognition memory. An analysis of the data, however, fails to support the underlying dissociation.

Clahsen proposes two distinct processing routes, for regularly and irregularly inflected forms, respectively, and thus is apparently making a psychological claim. We argue that his position, which embodies a strictly linguistic perspective, does not constitute a psychological processing model.