I argue that O'Regan & Noë's (O&N's) theory is in a no better position than any other theory to solve the “hard problem” of consciousness. Getting rid of the explanatory gap by exchanging sensorimotor contingencies for neural representations is an illusion.

Theories that make action central to perception are plausible, though largely untried, for space perception. However, explaining object recognition, and high-level perception generally, will require reference to representations of the world in some form. Nonetheless, action is central to cognition, and explaining high-level perception will be aided by integrating an understanding of action with other aspects of perception.

O'Regan & Noë (O&N) fail to address adequately the two most historically important reasons for seeking to explain visual experience in terms of internal representations. They are silent about the apparently inferential nature of perception, and mistaken about the significance of the phenomenology accompanying dreams, hallucinations, and mental imagery.

The target article proposes that visual experience arises when sensorimotor contingencies are exploited in perception. This novel analysis of visual experience fares no better than the other proposals that the article rightly dismisses, and for the same reasons. Extracting invariants may be needed for recognition, but it is neither necessary nor sufficient for having a visual experience. While the idea that vision involves the active extraction of sensorimotor invariants has merit, it does not replace the need for perceptual representations. Vision is not just for the immediate controlling of action; it is also for finding out about the world, from which inferences may be drawn and beliefs changed.

O'Regan & Noë (O&N) are pessimistic about the prospects for discovering the neural correlates of consciousness. They argue that there can be no one-to-one correspondence between awareness and patterns of neural activity in the brain, so a project attempting to identify the neural correlates of consciousness is doomed to failure. We believe that this degree of pessimism may be overstated; recent empirical data show some convergence in describing consistent patterns of neural activity associated with visual consciousness.

The research program defended by O'Regan & Noë (O&N) cannot give any plausible explanation for the fact that during REM-sleep the brain regularly generates subjective experiences (dreams) where visual phenomenology is especially prominent. This internal experience is almost invariably organized in the form of “being-in-the-world.” Dreaming presents a serious unaccountable anomaly for the sensorimotor research program and reveals that some of its fundamental assumptions about the nature of consciousness are questionable.

Two cross-modal experiments provide partial support for O'Regan & Noë's (O&N's) claim that sensorimotor contingencies mediate perception. Differences in locating a target sound accompanied by a spatially disparate neutral light correlate with whether the two stimuli were perceived as spatially unified. This correlation suggests that internal representations are necessary for conscious perception, which may also mediate sensorimotor contingencies.

Although O'Regan & Noë (O&N) claim that the world may serve as the viewers' external visual memory, findings from the field of memory research have demonstrated the existence of internal visual representations. These representations are stored in the viewer's brain, contain information regarding visual objects and their relations, guide subsequent exploration of the visual world and promote change detection.

The sensorimotor account of vision proposed by O'Regan & Noë (O&N) challenges the classical view of visual cognition as a process of mentally representing the world. Many infant cognition researchers would probably disagree. I describe the surprising ability of young infants to represent and reason about the physical world, and ask how this capacity can be explained in non-representational terms. As a first step toward answering this question, I suggest that recent models of embodied cognition may help illustrate a way of escaping the representational trap.

We suggest that the sensorimotor “theory” of vision is really an unstructured collection of separate ideas, and that much of the evidence cited in its favor at best supports only a subset of these ideas. As an example, we note that work on change blindness does not “vindicate” (or even speak to) much of the sensorimotor framework. Moreover, the ideas themselves are not always internally consistent. Finally, the proposed framework draws on ideas initially espoused by James Gibson, but does little to differentiate itself from those earlier views. For even part of this framework to become testable, it must specify which sources of evidence can support or contradict each of the component hypotheses.

In their target article, O'Regan & Noë (O&N) give convincing arguments for there being no elaborate internal representation of the outside world. We show two more categories of empirical results that can easily be understood within the view that the world serves as an outside memory that is probed only when specific information is needed.

O'Regan & Noë (O&N) present the most radical departure yet from traditional approaches to visual perception. However, internal representation cannot yet be abandoned. I will discuss: (1) recent evidence for very short-term pictorial representation of each fixation; (2) the possibility of abstract representation, largely unconsidered by the authors; and (3) that sensorimotor contingency theory requires internal visual retention and comparison.

One can support O'Regan & Noë's (O&N's) commitment to the active nature of vision and the importance of sensorimotor contingencies without joining them in rejecting any significant role for neurally realized visual representations in the process.

The sensorimotor account of perception is akin to Gibsonian direct realism. Both emphasize external properties of the world, challenging views based on the analysis of internal visual processing. To compare the role of distal and retinotopic parameters, distractor effect – an optomotor reaction of midbrain origin – is considered. Even in this case, permanence in the environment, not on the retina, explains the dynamics of habituation.

Perceptual phenomena reviewed by O'Regan & Noë (O&N) cannot be explained by bottom-up activity alone, but conventional interpretations suffice if perceptions are seen as activations of memory models of the outside world and its events. Motor involvement is necessary only during the phylogenetic and ontogenetic development of perceptual mechanisms.

The authors O'Regan & Noë (O&N) have ignored the case for the visual field as being non-epistemic evidence internal to the brain, having no pictorial similarity to the external input, and being material in ontological status. They are also not aware of the case for the evolutionary advantage of learning as the perceptual refashioning of such non-epistemic sensory evidence via motivated feedback in sensorimotor activity.

The most important clarification we bring in our reply to commentators concerns the problem of the “explanatory gap”: that is, the gulf that separates physical processes in the brain from the experienced quality of sensations. By adding two concepts (bodiliness and grabbiness) that were not stressed in the target article, we strengthen our claim and clarify why we think we have solved the explanatory gap problem, – not by dismissing qualia, but, on the contrary, by explaining why sensations have a “feel” and why “feels” feel the way they do. We additionally clarify our views on: internal representations (we claim internal representations cannot explain why sensation has a feel), on behaviorism (we are not behaviorists), on perception and action (we believe there can be perception without action), and on the brain (we believe the brain does do something important in perception).