Handbook of Psychology, Experimental Psychology

Irving B. Weiner, Alice F. Healy, Robert W. Proctor

• Publisher: Wiley
• Year: 2012
• Print ISBN: 9780470649930
• eBook ISBN: 9781118281949
• Edition: 2
• Topic: Psychology
• Subtopic: History & Theory in Psychology
• Index: Psychology

Psychology is of interest to academics from many fields, as well as to the thousands of academic and clinical psychologists and general public who can't help but be interested in learning more about why humans think and behave as they do. This award-winning twelve-volume reference covers every aspect of the ever-fascinating discipline of psychology and represents the most current knowledge in the field. This ten-year revision now covers discoveries based in neuroscience, clinical psychology's new interest in evidence-based practice and mindfulness, and new findings in social, developmental, and forensic psychology.

Part I

Modulatory Processes

Chapter 1

Consciousness

Ilya Farber and William P. Banks

Author's Note: Bill Banks passed away before revisions to this chapter could be completed. His coauthor and volume editors dedicate this work to his memory. Bill did much to bring the scientific study of consciousness to its current state of prominence and respectability, including cofounding the journal Consciousness and Cognition and organizing the inaugural meeting of the Association for the Scientific Study of Consciousness. He was a cheerful and tireless catalyst for scientific progress, and he will be sorely missed.

Brief History of the Study of Consciousness

What We Have Learned From Measures of Cognitive Functioning

Neuroscientific Approaches to Consciousness

Conclusion: The Future of Consciousness

References

Consciousness is an inclusive term for a number of central aspects of our personal existence. It is the arena of self-knowledge, the ground of our individual perspective, the realm of our private thoughts and emotions. It could be argued that these aspects of mental life are more direct and immediate than any perception of the physical world; indeed, it was this view that led Descartes to claim that the fact of our own thinking is the only empirical thing we know with mathematical certainty. Nevertheless, the study of consciousness within science has proven both challenging and controversial, so much so that some have doubted the appropriateness of addressing it within the tradition of scientific psychology. In the last few decades, however, new methods and technologies have yielded striking insights into the nature of consciousness. Neuroscience in particular has begun to reveal detailed connections between brain events, subjective experiences, and cognitive processes. The effect of these advances has been to give consciousness a central role both in integrating the diverse areas of psychology and in relating them to developments in neuroscience. In this chapter, we survey what has been discovered about consciousness; but because of the unique challenges that it poses, we also devote a fair amount of discussion to methodological and theoretical issues and consider ways in which prescientific models of consciousness exert a lingering (and potentially adverse) influence.

Consciousness has two features that pose special methodological challenges for scientific investigation. First, and best known, is its inaccessibility. A conscious experience is directly accessible only to the one person who has it, and even for that person it is often not possible to express precisely and reliably what has been experienced. As an alternative, psychologists have developed indirect measures (such as physiological measurements and reaction time) that permit reliable and quantitative measurement—but at the cost of raising new methodological questions about the relationship between these measures and consciousness itself.

The second challenging feature is that the single word consciousness is used to refer to a broad range of related but distinct phenomena (Farber & Churchland, 1995; Hill, 2009). Consciousness can mean not being knocked out or asleep; it can mean awareness of a particular stimulus, as opposed to unawareness or implicit processing; it can mean the basic functional state that is modulated by drugs, depression, schizophrenia, or REM sleep. It is the higher-order self-awareness that some species have and others lack; it is the understanding of one's own character and motivations that is gained only after careful reflection; it is the inner voice that expresses some small fraction of what is actually going on below the surface of the mind. On one very old interpretation, it is a transcendent form of unmediated presence in the world; on another, perhaps just as old, it is the inner stage on which ideas and images present themselves in quick succession.

Where scientists are not careful to focus their inquiry or to be explicit about what aspect of consciousness they are studying, this diversity can lead to confusion and talking at cross purposes. On the other hand, careful decomposition of the concept can point the way to a variety of solutions to the first problem, the problem of access. As it has turned out, the philosophical problems of remoteness and subjectivity need not always intrude in the study of more specific forms of consciousness such as those already mentioned; some of the more prosaic senses of consciousness have turned out to be quite amenable to scientific analysis. Indeed, a few of these, such as “awareness of stimuli” and “ability to remember and report experiences,” have become quite central to the domain of psychology, and must now by any measure be considered well studied.

In what follows, we provide a brief history of the early development of scientific approaches to consciousness, followed by more in-depth examinations of the two major strands in 20th-century research: the cognitive and the neuroscientific. In this latter area especially, the pace of progress quickened in the mid-1990s and then accelerated dramatically in the 2000s. Although no single model has yet won broad acceptance, it has become possible for theorists to advance hypotheses with a degree of empirical support and fine-grained explanatory power that was undreamed of 20 years ago (see, e.g., Welshon, 2011). In the concluding section, we offer some thoughts about the relationship between this scientific progress and everyday understanding.

Brief History of the Study of Consciousness

Ebbinghaus (1908, p. 3) remarked that psychology has a long past and a short history. The same could be said for the study of consciousness, except that the past is even longer and the scientific history shorter. The concept that the soul is the organ of experience and, hence, the organ of consciousness is ancient. This is a fundamental idea in the Platonic dialogues, as well as in the Upanishads, written about 600 years before Plato wrote and recording thinking that was then already ancient.

We could look at the soul as part of a prescientific explanation of mental events and their place in nature. In the mystical traditions, the soul is conceived as a substance different from the body that inhabits the body, survives its death (typically by traveling to a supernatural realm), and is the seat of thought, sensation, awareness, and usually the personal self. This doctrine is also central to Christian belief, and, for this reason, it has had enormous influence on Western philosophical accounts of mind and consciousness. The doctrine of soul or mind as an immaterial substance separate from body is not universal. Aristotle considered but did not accept the idea that the soul might leave the body and re-enter it (De Anima, 406; see Aristotle, 1991). His theory of the different aspects of “soul” is rooted in the functioning of the biological organism. The pre-Socratic philosophers for the most part had a materialistic theory of soul, as did Lucretius and the later materialists, and the conception of an immaterial soul is foreign to the Confucian tradition. The alternative prescientific conceptions of consciousness suggest that many problems of consciousness being faced today are not inevitable consequences of a scientific investigation of awareness. Rather, they may result from the specific assumption that mind and matter are entirely different substances.

The mind–body problem is the legendary and most basic problem posed by consciousness (Dardis, 2008). The question asks how subjective experience can be created by matter, or in more modern terms, by the interaction of neurons in a brain. Descartes (1596–1650; see Descartes, 1951) provided an answer to this question, and his answer formed the modern debate. Descartes's famous solution to the problem is that body and soul are two different substances. Of course, this solution is a version of the religious doctrine that soul is immaterial and has properties entirely different from those of matter. This position is termed dualism, and it assumes that consciousness does not arise from matter at all. The question then becomes not how matter gives rise to mind, because these are two entirely different kinds of substance, but how the two different substances can interact. If dualism is correct, a scientific program to understand how consciousness arises from neural processes is clearly a lost cause, and, indeed, any attempt to reconcile physics with experience is doomed. Even if consciousness is not thought to be an aspect of “soul-stuff,” its concept has inherited properties from soul-substance that are not compatible with our concepts of physical causality. These include free will, intentionality, and subjective experience. Further, any theorist who seeks to understand how mind and body “interact” is implicitly assuming dualism. To those who seek a unified view of nature, consciousness under these conceptions creates insoluble problems. The philosopher Schopenhauer called the mind–body problem the “worldknot” because of the seeming impossibility of reconciling the facts of mental life with deterministic physical causality. Chalmers (1996) termed the problem of explaining how brains give rise to subjective experience the “hard problem,” to distinguish it from the supposedly easier problem of explaining particular functions of consciousness.

Gustav Fechner, a physicist and philosopher, attempted to establish (under the assumption of dualism) the relationship between mind and body by measuring mathematical relations between physical magnitudes and subjective experiences of magnitudes (see, e.g., Dzhafarov & Colonius, 2011). Although no one would assert that he solved the mind–body problem, the methodologies he devised to measure sensation helped to establish the science of psychophysics.

The tradition of structuralism in the 19th century, in the hands of Wundt, Titchener, and many others (see Boring, 1942), led to very productive research programs. The structuralist research program could be characterized as an attempt to devise laws for the psychological world that have the power and generality of physical laws, clearly a dualistic project. Nevertheless, many of the “laws” and effects they discovered are still of interest to researchers (see, e.g., Day & Kimm, 2010).

The publication of John Watson's (1925) book Behaviorism marked the end of structuralism in the United States. Methodological and theoretical concerns about the current approaches to psychology had been brewing, but Watson's critique, essentially a manifesto, was thoroughgoing and seemingly definitive. For some 40 years afterwards, it was widely accepted that psychological research should study only publicly available measures such as accuracy, heart rate, and response time; that subjective or introspective reports were valueless as sources of data; and that consciousness itself could not be studied. Watson's arguments were consistent with views of science being developed by logical positivism, a school of philosophy that opposed metaphysics and argued that statements were meaningful only if they have empirically verifiable content. They were also consistent with ideas (later expressed by Wittgenstein, 1953, and Ryle, 1949) that people do not have privileged access to the inner workings of our minds through introspection, and, thus, that subjective reports were questionable sources of data. The mind (and the brain) were considered a black box, an area closed to investigation, and all theories were to be based on examination of observable stimuli and responses.

Research conducted on perception and attention during World War II, the development of the digital computer and information theory, and the emergence of linguistics as a scientific study of mind led to changes in every aspect of the field of psychology. It was widely concluded that the behavoristic strictures on psychological research had led to narrow theories of little relevance to interesting aspects of human performance. Chomsky's blistering attack on behaviorism (reprinted as Chomsky, 1996) might be taken as the 1960s equivalent of Watson's earlier behavioristic manifesto. Henceforth, researchers in psychology had to face the very complex mental processes demanded by linguistic competence, which were beyond the reach of methods countenanced by behaviorism. The mind was no longer a black box; theories based on a wide variety of techniques were used to develop rather complex theories of what went on in the mind. New theories and new methodologies emerged with dizzying speed, in what was termed the “cognitive revolution” (Gardner, 1985; Proctor & Vu, 2006).

We could consider ourselves to be in a second phase of this revolution, or possibly a new revolution built on the shoulders of the earlier one. This second revolution results from the progress that has been made by techniques that allow researchers to observe processing in the brain, including encephalography (EEG and ERP) and imaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). This last black box, the brain, is now being opened.

Our best chance of resolving the difficult problems of consciousness, including the “world knot” of the mind–body problem, would seem to come from the increasing depth and breadth of scientific methods available for relating matter (neural structure and function) to mind (psychological measures of perception and cognition). A true solution to the problem of consciousness may await conceptual change, or it may remain always at the tantalizing boundary where science intersects with philosophy; but at the very least, we must count it as progress that we have now entered an era in which the pursuit of questions about awareness, volition, and metacognition can be considered a task of normal science, and can be conducted with increasingly sophisticated technological tools.

What We Have Learned From Measures of Cognitive Functioning

Research on consciousness using strictly behavioral data has a history that long predates the present explosion of knowledge derived from neuroscience. This history includes sometimes-contr...

Table of contents

• Cover
• Title Page
• Copyright
• Editorial Board
• Handbook of Psychology Preface
• Volume Preface
• Contributors
• Part I: Modulatory Processes
• Part II: Sensory Processes
• Part III: Perceptual Processes
• Part IV: Attention and Action Processes
• Part V: Elementary Learning and Memory Processes
• Part VI: Complex Learning and Memory Processes
• Part VII: Language and Information Processing
• Part VIII: Thought Processes
• Part IX: Applications
• Author Index
• Subject Index