Consciousness, accessibility, and the mesh between psychology and neuroscience

Ned Block
2007 Behavioral and Brain Sciences  
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 see the problem in stark form if we ask how we can 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
more » ... son 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! This target article 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. I argue that we can find a neural realizer of this overflow if we assume that the neural basis of phenomenal consciousness does not include the neural basis of cognitive accessibility and that this assumption is justified (other things being equal) by the explanations it allows. Abstract: We agree that the relationship between phenomenology and accessibility can be fruitfully investigated via meshing, but we want to emphasise the importance of proper comparison between meshes, as well as considerations that make comparison especially difficult in this Commentary/Block: Consciousness, accessibility, and the mesh BEHAVIORAL AND BRAIN SCIENCES (2007) 30:5/6 Incomplete stimulus representations and the loss of cognitive access in cerebral achromatopsia Abstract: When processing of stimuli occurs without attention, phenomenal experience, as well as cognitive access, may be lost. Sensory representations are, however, constructed by neural machinery extending far beyond sensory receptors. In conditions such as cerebral achromatopsia incomplete sensory representations may still elicit Commentary/Block: Consciousness, accessibility, and the mesh Accessed, accessible, and inaccessible: Where to draw the phenomenal line Abstract: One can distinguish among perceptual states that have been accessed by working memory, states that are accessible, and states that are inaccessible. Block compellingly argues that phenomenology outstrips access but wrongly implies that phenomenology outstrips Commentary/Block: Consciousness, accessibility, and the mesh BEHAVIORAL AND BRAIN SCIENCES (2007) 30:5/6 Abstract: Our aim in this reply is to defend Global Workspace theory (GWT) from the challenge of Block's article. We argue that Block's article relies on an outdated and imprecise concept of access, and perpetuates a common misunderstanding of GWT that conflates the Commentary/Block: Consciousness, accessibility, and the mesh Abstract: Can phenomenality without access occur? We suggest that the crucial issue is not to show phenomenality that cannot be accessed, but whether phenomenality sometimes simply is not accessed. Considering this question leads to positing a distinct, second form of consciousness: Reflective consciousness. The most important form of access is then from phenomenal (first-order) to reflective (second-order) consciousness. Block's primary concern involves whether phenomenal consciousness (henceforth, P-consciousness) is independent of what he calls "cognitive accessibility." He argues yes (e.g., that P-consciousness can "overflow" access), and contrasts this view with that of others (e.g., Baars, Dehaene, Dennett, Naccache, etc.) who argue instead Commentary/Block: Consciousness, accessibility, and the mesh BEHAVIORAL AND BRAIN SCIENCES (2007) 30:5/6 Abstract: If the phenomenality of consciousness admits of degrees and can be partial and indeterminate, then Block's inference to the best explanation may need to be revaluated both in terms of the supposed data on phenomenal overflow and the range of alternatives against which his view is compared. Abstract: In this response to 32 commentators, I start by clarifying the overflow argument. I explain why the distinction between generic and specific phenomenology is important and why we are justified in acknowledging specific phenomenology in the overflow experiments. Other issues discussed are the relations among report, cognitive access, and attention; panpsychic disaster; the mesh between psychology and neuroscience; and whether consciousness exists.
doi:10.1017/s0140525x07002786 pmid:18366828 fatcat:hzmyn3d34rfdrdm5fejczzkufq