Computational functionalism claims that executing certain computations is sufficient for consciousness, regardless of the physical mechanisms implementing those computations. This view neglects a compelling alternative: that subcomputational biological mechanisms, which realize computational processes, are necessary for consciousness. By contrasting computational roles with their...
Visual experience can sometimes depart from visual performance, providing a powerful lens into the mechanisms generating conscious perception. In one proposed dissociation—subjective inflation—unattended locations in the periphery appear stronger than attended ones despite equated performance. Subjective inflation has played a central role in motivating theories of consciousness that reject the...
Abstract Brain waves driven by electrochemical processing may be necessary for consciousness, and if so, that will challenge consciousness in artificial intelligence (AI) and perhaps in some invertebrates.
Disputes between rival theories of consciousness have often centered on whether perceptual contents can be decoded from the prefrontal cortex (PFC). Failures to decode from the PFC are taken to challenge 'cognitive' theories of consciousness such as the global workspace theory and higher-order monitoring theories, and decoding successes have been taken to confirm these theories. However, PFC...
Abstract This chapter is about experiments that aim to isolate the neural basis of conscious perception, but in line with the methodology discussed in Chapter 1, I am putting the issues of consciousness to one side, focusing on the neural basis of perception itself as contrasted with the neural basis of perceptual judgment. The chapter discusses the “no-report” paradigm not from the point of...
Experiments suggest that conscious decisions to act may be initiated by unconscious neural events that precede the decision. Some have concluded that unconscious neural events are sufficient to cause both the decision to act and the action, so consciousness has no causal efficacy in producing the action. Here, I explain why this reasoning is fallacious in terms that apply to all mental events,...
A central debate in philosophy and neuroscience pertains to whether PFC activity plays an essential role in the neural basis of consciousness. Neuroimaging and electrophysiology studies have revealed that the contents of conscious perceptual experience can be successfully decoded from PFC activity, but these findings might be confounded by postperceptual cognitive processes, such as thinking,...
Scientific research on consciousness is critical to multiple scientific, clinical, and ethical issues. The growth of the field could also be beneficial to several areas including neurology and mental health research. To achieve this goal, we need to set funding priorities carefully and address problems such as job creation and potential media misrepresentation.
The success of the Bayesian perspective in explaining perceptual phenomena has motivated the view that perceptual representation is probabilistic. But if perceptual representation is probabilistic, why does normal conscious perception not reflect the full probability functions that the probabilistic point of view endorses? For example, neurons in cortical area MT that respond to the direction...
In their Review “What is consciousness, and could machines have it?” (27 October 2017, p. [486][1]), S. Dehaene et al. argue that the science of consciousness indicates that we are not on the verge of creating conscious machines. However, Dehaene et al. ask and answer the wrong questions. To
In our ASSC20 symposium, “Does unconscious perception really exist?”, the four of us asked some difficult questions about the purported phenomenon of unconscious perception, disagreeing on a number of points. This disagreement reflected the objective of the symposium: not only to come together to discuss a single topic of keen interest to the ASSC community, but to do so in a way that would...
A recent fMRI study by Webb et al. (Cortical networks involved in visual awareness independent of visual attention, Proc Natl Acad Sci U S A 2016;113:13923-28) proposes a new method for finding the neural correlates of awareness by matching attention across awareness conditions. The experimental design, however, seems at odds with known features of attention. We highlight logical and...
Nobel Laureate Paul Krugman once remarked that engaging the public about economic theories is hard, partly because everybody feels they are entitled to opine about the economy even if they have no formal training in economics (see: http://web.mit.edu/krugman/www/virus.html). Perhaps because we are all conscious, the same sometimes happens in the field of consciousness research. Like Krugman, we...
Can we consciously see more items at once than can be held in visual working memory? This question has eluded resolution because the ultimate evidence is subjects' reports in which phenomenal consciousness is filtered through working memory. However, a new technique makes use of the fact that unattended 'ensemble properties' can be detected 'for free' without decreasing working memory capacity.
The Anna Karenina theory says: all conscious states are alike; each unconscious state is unconscious in its own way. This paper argues that many components have to function properly to produce consciousness, but failure in any one of many different ones can yield an unconscious state in different ways. In that sense the Anna Karenina theory is true. But in another respect it is false: kinds of...
Abstract Much of recent philosophy of perception is oriented towards accounting for the phenomenal character of perception—what it is like to perceive—in a non‐mentalistic way—that is, without appealing to mental objects or mental qualities. In opposition to such views, I claim that the phenomenal character of perception of a red round object cannot be explained by or reduced to direct...
There are two concepts of consciousness that are easy to confuse with one another, access-consciousness and phenomenal consciousness. However, just as the concepts of water and H 2 O are different concepts of the same thing, so the two concepts of consciousness may come to the same thing in the brain. The focus of this paper is on the problems that arise when these two concepts of consciousness...
This article concerns the interplay between two issues that involve both philosophy and neuroscience: whether the content of phenomenal consciousness is 'rich' or 'sparse', whether phenomenal consciousness goes beyond cognitive access, and how it would be possible for there to be evidence one way or the other.
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...
Professor Block has written extensively on a number of topics in the philosophy of mind, from consciousness to cognitive science, and is particularly known for his work on Functionalism. Many of his papers are collected in Consciousness, Functionalism, and Representation (2007). This interview was conducted in New Haven on March 6th, 2007.
AbstractThere are many problems of consciousness, but the most significant of them is: how is it possible to explain consciousness in terms of its neural basis?
Neuroscientists continue to search for "the" neural correlate of consciousness (NCC). In this article, I argue that a framework in which there are at least two distinct NCCs is increasingly making more sense of empirical results than one in which there is a single NCC. I outline the distinction between phenomenal NCC and access NCC, and show how they can be distinguished by experimental...
T. H. Huxley famously said ‘How it is that anything so remarkable as a state of consciousness comes about as a result of irritating nervous tissue, is just as unaccountable as the appearance of Djin when Aladdin rubbed his lamp.’ We do not see how to explain a state of consciousness in terms of its neurological basis. This is the Hard Problem of Consciousness. The aim of this paper is to...
Abstract The concept of H2O and the concept of water are two concepts of the same thing, as are the concepts of temperature and mean molecular kinetic energy. But something like the converse case is also common. In the seventeenth century, there were two concepts whose referents did not coincide, both denoted by the ambiguous phrase now translated as ‘degree of heat’. When they measured “degree...
The greatest chasm in the philosophy of mind -maybe even all of philosophydivides two perspectives on consciousness. The two perspectives differ on whether there is anything in the phenomenal character of conscious experience that goes beyond the intentional, the cognitive and the functional. A convenient terminological handle on the dispute is whether there are qualia. Those who think that the...