How should we characterize the functional role of conscious visual experience? In particular, how do the conscious contents of visual experience guide, bear upon, or otherwise inform our ongoing motor activities? According to an intuitive and (I shall argue) philosophically influential conception, the links are often quite direct. The contents of conscious visual experience, according to this conception, are typically active in the control and guidance of our fine-tuned, real-time engagements with the surrounding three-dimensional world. But this idea (which I (...) shall call the Assumption of Experience-Based Control) is hostage to empirical fortune. It is a hostage, moreover, whose safety is in serious doubt. Thus Milner and Goodale (1995) argue for a deep and abiding dissociation between the contents of conscious seeing, on the one hand, and the resources used for the on-line guidance of visuo-motor action, on the other. This ‘dual visual systems’ hypothesis, which finds many echoes in various other bodies of cognitive scientific research, poses a prima facie challenge to the Assumption of Experience-Based Control. More importantly, it provides (I shall argue) fuel for an alternative and philosophically suggestive account of the functional role of conscious visual experience. (shrink)

In Enchanted Looms , Rodney Cotterill defends the hypothesisthat conscious sensory experience depends on motor response. Thepositive evidence for this hypothesis is inconclusive, andnegative evidence can be marshaled against it. I present analternative hypothesis according to which consciousness involvesintermediate level sensory processing, attention, and workingmemory. The circuitry of consciousness can be dissociated fromaction systems and may mark an evolutionary advance from a priorphylogenetic stage in which motor outputs and sensory inputswere more intimately bound.

The prefrontal cortex has long been suspected to play an important role in cognitive control, in the ability to orchestrate thought and action in accordance with internal goals. Its neural basis, however, has remained a mystery. Here, we propose that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them. They provide bias signals to other brain structures whose net effect is to guide the flow of (...) activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task. We review neurophysiological, neurobiological, neuroimaging, and computational studies that support this theory and discuss its implications as well as further issues to be addressed. (shrink)

In _Action in Perception _Alva No develops and presents a sensorimotor account of vision and of visual consciousness. According to such an account seeing (and indeed perceiving more generally) is analysed as a kind of skilful bodily activity. Such a view is consistent with the emerging emphasis, in both philosophy and cognitive science, on the critical role of embodiment in the construction of intelligent agency. I shall argue, however, that the full sensorimotor model faces three important challenges. The first is (...) to negotiate a path between two prima facie unsatisfactory readings of the central claim that conscious perceptual experience is constituted by knowledge of patterns of sensorimotor dependence. The second is to convince us that the sensorimotor contribution, in such cases, is actually constitutive of perceptual experience rather than merely causally implicated in the origination of such experience.² And the third is to respond to the important challenge raised by what I will dub 'sensorimotor summarizing' models of the relation between conscious experience and richly detailed sensorimotor routines. According to such models³ conscious perceptual experience only rather indirectly reflects the rich detail of our actual sensorimotor engagements, which are instead lightly sampled as a coarse guide, optimized for planning and reasoning, and geared and filtered according to current needs and purposes. (shrink)

Milner and Goodale review a wealth of evidence, much of it from their own research, showing that visually guided behavior and perception are controlled by two separate and quasi-independent 'visual brains'. Early evidence showed that motor ability was sometimes preserved despite simultaneous perceptual illusions, and work with patients has differentiated the two systems neurologically. Of the two visual systems, the motor system is less well known: it has a body-based frame of reference, but no memory and limited pattern-recognition capacity.

The character of computational modelling of cognition depends on an underlying theory of representation. Classical cognitive science has exploited the syntax/semantics theory of representation that derives from logic. But this has had the consequence that the kind of psychological explanation supported by classical cognitive science is " _conceptualist_: " psychological phenomena are modelled in terms of relations that hold between concepts, and between the sensors/effectors and concepts. This kind of explanation is inappropriate for the Proper Treatment of Connectionism.

We seem, or so it seems to some theorists, to experience a rich stream of highly detailed information concerning an extensive part of our current visual surroundings. But this appearance, it has been suggested, is in some way illusory. Our brains do not command richly detailed internal models of the current scene. Our seeings, it seems, are not all that they seem. This, then, is the Grand Illusion. We think we see much more than we actually do. In this paper (...) I shall (briefly) rehearse the empirical evidence for this rather startling claim, and then critically examine a variety of responses. One especially interesting response is a development of the so-called ‘skill theory’, according to which there is no illusion after all. Instead, so the theory goes, we establish the required visual contact with our world by an ongoing process of active exploration, in which the world acts as a kind of reliable, interrogable, external memory (Noe, Pessoa and. (shrink)