Consciousness

by

Bruce Bridgeman

• LAST REVIEWED: 08 May 2015
• LAST MODIFIED: 29 October 2013
• DOI: 10.1093/obo/9780199828340-0068

Introduction

Though consciousness is central to human experience, it has been little studied in psychology. An important part of psychological inquiry in the 19th century, it languished for most of the 20th century with the insistence on quantitative methods and replicability. In the United States, the influential behaviorist movement explicitly rejected study of internal states, basing its psychology instead on relating stimulus to response. New methods in both neurophysiology and cognitive psychology have reopened the study of consciousness, however, relating it to essential functions of human cognition. If we assume that consciousness is a complex enough phenomenon that genes are required to support it, we can conclude from evolutionary theory that consciousness has a function. Since it is universal to all people, like eyes or hearts, the neurological machinery that supports it must rely on genes that are selected for. In contrast, a genetically supported trait that is not useful tends to disappear. Fish trapped in dark caves, for instance, lose their eyes over many generations because mutations in the genes supporting eyes are no longer selected against. If the still-unknown array of genes supporting consciousness is maintained, there must be some essential capabilities that consciousness bestows. Evolutionary theory does not tell us what those capabilities are, however. That is the subject of recent and current research.

General Overviews

There are no general college-level textbooks devoted exclusively to consciousness. The closest approximation is the brief book Friedenberg 2013, though it emphasizes consciousness and attention as applied to vision. Several books, however, include good introductions to a wide variety of approaches. Uncovering the mechanisms of consciousness has been identified as one of the most important problems in science (Crick 1995), yet consciousness has proved paradoxically difficult to define. The common definition invokes awareness, which merely adds a near-synonym without defining either term. Baars and Gage 2010 prominently includes consciousness among the core issues in cognitive neuroscience. Banks 2009 provides a definitive group of chapters by leading scholars on their approaches to consciousness. Block 2004 defines several levels or kinds of consciousness. Another approach is through language: if one can talk about a perception or experience, or at least attempt to do so, then that event is conscious; otherwise, it is not. This approach is related to memory, where consciousness is defined as that which can be recalled. Eagleman 2011 covers it all, basing its approach not on the conscious but on the unconscious that defines most of what the brain does. The sense of agency, that we are in conscious control of our actions, is tested to the extreme in Wegner 2002. Many of these sources also address the so-called mind/brain problem, the relationship between a mind that seems personal and a brain that operates by the biological principles of neurophysiology. Mind, though, is what the brain does, just as digestion is what the stomach does. Opening up the stomach does not reveal digestion any more than opening up the brain reveals mind. Mind is a verb, something the brain does. It won’t be found sitting in some brain module.

• Baars, B. J., and N. M. Gage, eds. 2010. Cognition, brain and consciousness. 2d ed. New York: Elsevier.

  Written primarily as an introduction to cognitive neuroscience, the book reflects the authors’ expertise in but does not call for a neuroscience background.

• Banks, W. P., ed. 2009. Encyclopedia of consciousness. 2 vols. Amsterdam: Elsevier.

  A collection of articles by leading scholars on what consciousness is and what functions it might fulfill.

• Block, N. 2004. Two neural correlates of consciousness. Trends in Cognitive Sciences 9:46–52.

  DOI: 10.1016/j.tics.2004.12.006

  Block, a philosopher, distinguishes access and phenomenal consciousness, asserting that separate neural correlates should be expected for each. Available online for purchase or by subscription.

• Crick, F. 1995. The astonishing hypothesis: The scientific search for the soul. New York: Touchstone.

  In one of the contributions that revived the scientific study of consciousness, Crick’s Nobel Prize gave the field legitimacy.

• Eagleman, D. 2011. Incognito: The secret lives of the brain. New York: Pantheon.

  The brain is conceived as a cluster of semi-autonomous agents, most of them operating unconsciously, each with a specialized job. The book asks among other things whether we are responsible for our actions if those actions are largely driven by unconscious brain mechanisms. A compelling read, with a lot of surprises. Highly recommended.

• Friedenberg, J. 2013. Visual attention and consciousness. New York: Psychology Press.

  The first two chapters treat general problems of consciousness, and the last chapter reviews some of the major theories. The remainder of the book applies these ideas to the visual system.

• Wegner, D. M. 2002. The illusion of conscious will. Cambridge, MA: MIT Press.

  This is a terrifying book. In the laboratory Wegner and colleagues can make people produce actions without being aware that they are producing them, or experience actions that they think they are producing although they are not. Unconscious processing dominates the work of the brain, and people have little knowledge of what is happening there.