Consciousness and the Brain

This Ciba Foundation international symposium in 1992, which I proposed to the foundation in 1991, gathered together 25 of the most prominent philosophers and scientists working on consciousness at that time. What is particularly interesting about this collection is that each paper was followed by an in-depth discussion with the participants, which was recorded and then edited for publication as an accompaniment to each paper. Consequently, the collection presents a representative snapshot of the philosophical and scientific problems of consciousness and the varied approaches to their solution at that time.

In everyday life we take it for granted that we have conscious control of some of our actions and that the part of us that exercises control is the conscious mind.  Psychosomatic medicine also assumes that the conscious mind can affect body states, and this is supported by evidence that the use of imagery, hypnosis, biofeedback and other ‘mental interventions’ can be therapeutic in a variety of medical conditions.  However, there is no accepted theory of mind/body interaction and this has had a detrimental effect on the acceptance of mental causation in science, philosophy and in many areas of clinical practice. Biomedical accounts typically translate the effects of mind into the effects of brain functioning, for example, explaining mind/body interactions in terms of the interconnections and reciprocal control of cortical, neuroendocrine, autonomic and immune systems.  While such accounts are instructive, they are implicitly reductionist, and beg the question of how conscious experiences could have bodily effects.  On the other hand, non-reductionist accounts have to cope with three problems: 1) The physical world appears causally closed, which would seem to leave no room for conscious intervention. 2) One is not conscious of one’s own brain/body processing, so how could there be conscious control of such processing? 3) Conscious experiences appear to come too late to causally affect the processes to which they most obviously relate.  This paper suggests a way of understanding mental causation that resolves these problems. It also suggests that “conscious mental control” needs to be partly understood in terms of the voluntary operations of the preconscious mind, and that this allows an account of biological determinism that is compatible with experienced free will.

There have been various attempts to apply Darwinian evolutionary theory to an understanding of the human condition within psychology and the social sciences. This paper evaluates whether Darwinian Theory can explain human consciousness. Starting with a brief definition of phenomenal consciousness and the central features of evolutionary theory, the paper examines whether random variations in the genome that confer a selective, reproductive advantage can explain both the emergence of consciousness and its varied forms. To inform the discussion, the paper reviews what is known about the conditions for consciousness within the human mind/brain, understood in both structural (neural) terms and functional terms (in terms of human information processing), and concludes that “random variations in the genome” provide no explanatory mechanism for why some neural activities (but not others) are accompanied by consciousness. The paper then evaluates the many functional advantages that have been proposed for various forms of phenomenal consciousness once they emerge, and concludes that, on close examination, phenomenal experiences themselves do not carry out the information processing functions attributed to them, which challenges the Darwinian requirement that they could only have persisted (once emergent) it they enhanced reproductive fitness. The paper turns finally to what can be said about wider distribution of consciousness in non-humans, contrasting discontinuity theories with continuity theories. Discontinuity theories argue for a critical functional transition that “switches on consciousness” while continuity theories argue for a gradual transition in consciousness from unrecognisable to recognisable. All theories accept that there is an intimate, natural relationship of conscious experiences with their associated material forms. Consequently, as the material forms evolve, their associated experiences co-evolve—suggesting an indirect mechanism by which the emergence of species-specific forms of consciousness can be influenced by Darwinian evolution. It also allows a non-reductive understanding of human consciousness within the social sciences.

Modern consciousness studies are in a healthy state, with many progressive empirical programmes in cognitive science, neuroscience and related sciences, using relatively conventional third-person research methods. However not all the problems of consciousness can be resolved in this way. These problems may be grouped into problems that require empirical advance, those that require theoretical advance, and those that require a re-examination of some of our pre-theoretical assumptions. I give examples of these, and focus on two problems—what consciousness is, and what consciousness does—that require all three.  In this, careful attention to conscious phenomenology and finding an appropriate way to relate first-person evidence to third-person evidence appears to be central to progress. But we may also need to re-examine what we take to be “natural facts” about the world, and how we can know them. The same appears to be true for a trans-cultural understanding of consciousness that combines classical Indian phenomenological methods with the third-person methods of Western science.

This introductory chapter was written in 1995, for a new book of review articles on the emerging science of consciousness, specifically aimed at undergraduate and postgraduate students by experts in the relevant fields. Following on a brief history, the chapter moves on to definitions of consciousness and background philosophical issues, and then introduces a unified, non-reductionist scientific approach. It then summarises major issues for studies of consciousness in cognitive psychology, including studies of attention, memory, the extent of preconscious analysis and the relation of consciousness more generally to human information processing. It then turns to the neuropsychology of consciousness, starting with some apparent neural requirements for the transition from preconscious to conscious states, various clinical dissociations of consciousness, conditions for integration (or binding) and, finally, clinical applications, including different forms of mind/body interaction and evidence for the causal efficacy of mental states. The chapter concludes that while some of the ancient problems of consciousness remain unsolved, its study has become the subject of a rapidly developing science.

There are two quite distinct ways in which events that we normally think of as “physical” relate in an intimate way to events that we normally think of as “psychological”. One intimate relation occurs in exteroception at the point where events in the world become events as-perceived. The other intimate relationship occurs at the interface of conscious experience with its neural correlates in the brain. The chapter examines each of these relationships and positions them within a dual-aspect, reflexive model of how consciousness relates to the brain and external world. The chapter goes on to provide grounds for viewing mind and nature as fundamentally psychophysical, and examines similar views as well as differences in previously unpublished writings of Wolfgang Pauli, one of the founders of quantum mechanics.
Added note for 2013 upload: the chapter goes on to give an analysis of how first and third person complementarity in psychology both resembles and differs from complementarity in physics, and also summarises how the dual-aspect monism developed by Pauli/Jung and Velmans resembles and differs from the naturalistic dualism (sometimes referred to as double aspect monism) developed by Chalmers.

This chapter from Understanding Consciousness (2009) provides the fullest account (in my writings) of the function of consciousness, updating the account developed in the first edition of the book and the analyses originally presented in " Is human information processing conscious? " (1991a) (a target article in The Behavioral and Brain Sciences) and my subsequent replies to peer commentaries in Velmans (1991b, 1993, 1996). The chapter describes the different ways in which conscious mental states appear to interact with states of the brain and the apparently paradoxical nature of such causal interactions. After surveying the strengths and weaknesses of dualist and reductionist accounts of such interactions it goes on to develop a form of non-reductionist, dual-aspect monism in which first-and third-person accounts of mental functioning are complementary and mutually irreducible. This specifies some of the functional constraints on how states of consciousness are likely to relate to their neural correlates, how perspectival switching between first-and third person accounts of mental functioning can cross the " explanatory gap " between these to provide a form of compatibilism, and how to fill that explanatory gap with a dual-aspect theory of information processing. The chapter then gives a simple, intuitively plausible account of all forms of mental/physical causal interaction. The chapter then turns to the deeper paradoxes surrounding " conscious causation ". For example, we have little introspective awareness of how " conscious processes " actually operate, which suggests that so-called " conscious processes " largely operate in unconscious fashion. Careful examination of how conscious phenomenology relates to its associated processing also reveals that it generally follows the processing to which it most closely relates—in which case it comes too late to causally affect that processing. Given this, in what sense could " conscious causation " be conscious? At the same time, it seems absurd to deny the central role of consciousness in human mental life. How, without it, could we perceive, think, read, speak, or engage in other complex, novel mental tasks? To resolve such apparent paradoxes the chapter argues that one needs to understand (a) the relationship of phenomenal consciousness to focal-attentive processing, (b) the three distinct senses in which a mental process can be said to be " conscious " and (c) the role of consciousness in both representation and knowledge. Finally, and centrally one needs to understand how phenomenal consciousness enables one to " real-ize " the world—it is through consciousness that existence becomes subjectively real.