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Chapter Three: States of Consciousness

Table of Contents

Part One: Consciousness

Part Two: Sleep

Part Three: Hypnosis

Part Four: Meditation

Part Five: Psychoactive Drugs

Overview of Chapter 3: States of Consciousness

Consciousness was once the main focus of psychology. The field began by defining itself as the science of consciousness.

After decades of fruitless attempts to study consciousness by looking within (introspectio) the discipline of psychology took a radical turn away from introspection in the early 1900s. Behaviorists followed the lead of hard sciences like physics and chemistry, emphasizing observable behavior. By the 1950s few psychologists discussed consciousness.

Fifty to sixty years later, after the cognitive and neuroscience revolutions, the pendulum had swung back. For example, in the late 1990s over 30 scholarly books speculated about the nature of consciousness.

We will address some of the basic issues such as the distinction between conscious and unconscious thought and evidence for automaticity in human action. We will also review some altered states of conscious­ness, such as those associated with sleep, hypnosis, meditation, and psychoactive drugs.

Sleep and dreaming are states of consciousness that can be very strange but are experienced by everybody. If you have peculiar dreams while studying this chapter, do not be surprised; studying sleep and dreaming can have that effect. Some people claim never to remember dreams; we will discuss that, too.

Hypnosis is another "fun" topic that alternately fascinates and annoys psychologists. We will strive for a calm, reasoned discussion of hypnosis, despite suggesting it might be an unnecessary construct in Chapter 1. Even if you just call it suggestibility, the psychological phenomenon is compelling and important.

How this chapter is organized

The chapter begins with a brief discussion of consciousness as a research topic. We will examine the idea of two distinct modes of consciousness: analytic, serial process­ing and holistic, parallel processing.

The next section of the chapter deals with sleep, particularly the findings from the era known as the Golden Age of Sleep Research, such as the discovery of REM sleep and its correlation with dreaming. We will review normal sleep phenomena, and then sleep disorders.

After sleep we discuss hypnosis and meditation, with a review of findings and claims about mindfulness, a modern version of meditation. Then we turn to hypnosis and its relationship to phenomena of suggestion.

The last part of the chapter discusses psychoactive drugs. We will review behavioral and psychological phenomena associated with various drugs.

Related topics in other chapters

Memory distortion and confabulation, raised here in connection with hypnosis, are discussed more detail in Chapter 6 (Memory), Chapter 13 (Therapies) and Chapter 14 (Frontiers of Psychology). Conscious and unconscious thought processes are discussed throughout Chapter 7 (Cognition).

The mental processes of animals are in Chapter 8 (Animal Behavior and Cognition). Emotional states are discussed in Chapter 9 (Motivation and Emotion).

Some disordered and abnormal states of conscious (depersonalization, psychosis, and more) are described in Chapter 12 (Abnormal Psychology). The topic of drug addiction is covered in Chapter 14, Frontiers of Psychology.

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