Amidst the many brain events evoked by a visual stimulus, which are specifically associated with conscious perception, and which merely reflect non-conscious processing? Several recent neuroimaging studies have contrasted conscious and non-conscious visual processing, but their results appear inconsistent. Some support a correlation of conscious perception with early occipital events, others with late parieto-frontal activity. Here we attempt to make sense of those dissenting results. On the basis of a minimal neuro-computational model, the global neuronal workspace hypothesis, we propose a (...) taxonomy which distinguishes between vigilance and access to conscious report, as well as between subliminal, preconscious and conscious processing. We suggest that these distinctions map onto different neural mechanisms, and that conscious perception is systematically associated with a sudden surge of parieto-frontal activity causing top-down amplification. (shrink)

How can we disentangle the neural basis of phenomenal consciousness from the neural machinery of the cognitive access that underlies reports of phenomenal consciousness? We can see the problem in stark form if we ask how we could tell whether representations inside a Fodorian module are phenomenally conscious. The methodology would seem straightforward: find the neural natural kinds that are the basis of phenomenal consciousness in clear cases when subjects are completely confident and we have no reason to doubt their (...) authority, and look to see whether those neural natural kinds exist within Fodorian modules. But a puzzle arises: do we include the machinery underlying reportability within the neural natural kinds of the clear cases? If the answer is ‘Yes’, then there can be no phenomenally conscious representations in Fodorian modules. But how can we know if the answer is ‘Yes’? The suggested methodology requires an answer to the question it was supposed to answer! The paper argues for an abstract solution to the problem and exhibits a source of empirical data that is relevant, data that show that in a certain sense phenomenal consciousness overflows cognitive accessibility. The paper argues that we can find a neural realizer of this overflow if assume that the neural basis of phenomenal consciousness does not include the neural basis of cognitive accessibility and that this assumption is justified by the explanations it allows. (shrink)

The search for neural correlates of consciousness (or NCCs) is arguably the cornerstone in the recent resurgence of the science of consciousness. The search poses many difficult empirical problems, but it seems to be tractable in principle, and some ingenious studies in recent years have led to considerable progress. A number of proposals have been put forward concerning the nature and location of neural correlates of consciousness. A few of these include.

Consciousness is a mongrel concept: there are a number of very different "consciousnesses." Phenomenal consciousness is experience; the phenomenally conscious aspect of a state is what it is like to be in that state. The mark of access-consciousness, by contrast, is availability for use in reasoning and rationally guiding speech and action. These concepts are often partly or totally conflated, with bad results. This target article uses as an example a form of reasoning about a function of "consciousness" based on (...) the phenomenon of blindsight. Some information about stimuli in the blind field is represented in the brains of blindsight patients, as shown by their correct "guesses," but they cannot harness this information in the service of action, and this is said to show that a function of phenomenal consciousness is somehow to enable information represented in the brain to guide action. But stimuli in the blind field are BOTH access-unconscious and phenomenally unconscious. The fallacy is: an obvious function of the machinery of access-consciousness is illicitly transferred to phenomenal consciousness. (shrink)

Since the advent of behaviorism the question of volition or "will" has been largely neglected. We consider evidence indicating that two identical behaviors may be quite distinct with respect to volition: For instance, with practice the details of predictable actions become less and less voluntary, even if the behavior itself does not visibly change. Likewise, people can voluntarily imitate involuntary slips they have just made. Such examples suggest that the concept of volition applies not to visible behavior per se, but (...) to the control system that guides behavior. Involuntary events include both automatisms and counter voluntary actions such as slips. An adequate theory of voluntary control must account for the entire set of such pairs of voluntary/involuntary contrasts. The problem of volition highlights core psychological issues. Voluntary acts are consistent with one′s current dominant goals. Volition and consciousness are intimately related. Consciousness of an action seems to recruit unconscious resources that help in planning, executing, and monitoring a voluntary act. Conversely, losing conscious access to an action seems to produce a loss of voluntary control. However, voluntary actions are not wholly conscious. It appears that we only need conscious access to nonroutine choice-points in the flow of control; routine aspects are handled unconsciously. The goals that guide voluntary acts often encounter conflict, either from reality or from other goals, and emotions are widely believed to result from appraisals of such conflicts. Finally, there is a close connection between countervoluntary slips and the symptoms of clinical pathology, which involve a loss of voluntary control over speech, action, feeling, imagery, or thought. A modern version of William James′ ideomotor theory is proposed, based on Global Workspace theory. The theory shows how a conscious goal image could activate unconscious plans and automatisms that shape a voluntary act. Conscious feedback from the act serves to communicate success or failure to many unconscious routines, which may then adapt cooperatively to shape future actions. (shrink)

Since the advent of behaviorism the question of volition or "will" has been largely neglected. We consider evidence indicating that two identical behaviors may be quite distinct with respect to volition: For instance, with practice the details of predictable actions become less and less voluntary, even if the behavior itself does not visibly change. Likewise, people can voluntarily imitate involuntary slips they have just made. Such examples suggest that the concept of volition applies not to visible behavior per se, but (...) to the control system that guides behavior. Involuntary events include both automatisms and counter voluntary actions such as slips . An adequate theory of voluntary control must account for the entire set of such pairs of voluntary/involuntary contrasts. The problem of volition highlights core psychological issues. Voluntary acts are consistent with one′s current dominant goals. Volition and consciousness are intimately related. Consciousness of an action seems to recruit unconscious resources that help in planning, executing, and monitoring a voluntary act. Conversely, losing conscious access to an action seems to produce a loss of voluntary control. However, voluntary actions are not wholly conscious. It appears that we only need conscious access to nonroutine choice-points in the flow of control; routine aspects are handled unconsciously. The goals that guide voluntary acts often encounter conflict, either from reality or from other goals, and emotions are widely believed to result from appraisals of such conflicts . Finally, there is a close connection between countervoluntary slips and the symptoms of clinical pathology, which involve a loss of voluntary control over speech, action, feeling, imagery, or thought. A modern version of William James′ ideomotor theory is proposed, based on Global Workspace theory . The theory shows how a conscious goal image could activate unconscious plans and automatisms that shape a voluntary act. Conscious feedback from the act serves to communicate success or failure to many unconscious routines, which may then adapt cooperatively to shape future actions. (shrink)