Chapter 7. States of Consciousness

Chapter 7 Introduction

Charles Stangor; Jennifer Walinga; and Lee Sanders

An Unconscious Killing

During the night of May 23, 1987, Kenneth Parks, a 23-year-old Canadian with a wife, a baby daughter, and heavy gambling debts, got out of his bed, climbed into his car, and drove 15 miles to the home of his wife’s parents in the suburbs of Toronto. There, he attacked them with a knife, killing his mother-in-law and severely injuring his father-in-law. Parks then drove to a police station and stumbled into the building, holding up his bloody hands and saying, “I think I killed some people…my hands.” The police arrested him and took him to a hospital, where surgeons repaired several deep cuts on his hands. Only then did police discover that he had indeed assaulted his in-laws.

Parks claimed that he could not remember anything about the crime. He said that he remembered going to sleep in his bed, then awakening in the police station with bloody hands, but nothing in between. His defence was that he had been asleep during the entire incident and was not aware of his actions (Martin, 2009).

Not surprisingly, no one believed this explanation at first. However, further investigation established that he did have a long history of sleepwalking, he had no motive for the crime, and despite repeated attempts to trip him up in numerous interviews, he was completely consistent in his story, which also fit the timeline of events. Parks was examined by a team of sleep specialists, who found that the pattern of brainwaves that occurred while he slept was very abnormal (Broughton, Billings, Cartwright, & Doucette, 1994). The specialists eventually concluded that sleepwalking, probably precipitated by stress and anxiety over his financial troubles, was the most likely explanation of his aberrant behaviour. They also agreed that such a combination of stressors was unlikely to happen again, so he was not likely to undergo another such violent episode and was probably not a hazard to others. Given this combination of evidence, the jury acquitted Parks of murder and assault charges. He walked out of the courtroom a free man (Wilson, 1998).

Consciousness is defined as our subjective awareness of ourselves and our environment (Koch, 2004). The experience of consciousness is fundamental to human nature. We all know what it means to be conscious, and we assume (although we can never be sure) that other human beings experience their consciousness similarly to how we experience ours.

Philosophies of human consciousness inform the present study of behaviour and mental processes. Socrates (490–399 BC) argued that free will is limited after he noticed that people often do things they really do not want to do. He called this akrasia or a lack of control over oneself. A few centuries later, the Roman thinker Plotinus (AD 205–270) was presumably the first to allude to the possibility of unconscious psychological processes where he noted that the absence of conscious perception does not necessarily prove the absence of mental activity.

Some philosophers and religious practices argue that the mind (or soul) and the body are separate entities. For instance, the French philosopher René Descartes (1596-1650), shown in Figure 7.1, was a proponent of dualism, the idea that the mind, a nonmaterial entity, is separate from (although connected to) the physical body. In contrast to the dualists, psychologists believe that consciousness (and thus the mind) exists in the brain, not separate from it. In fact, psychologists believe that consciousness is the result of the activity of the many neural connections in the brain, and that we experience different states of consciousness depending on what our brain is currently doing (Dennett, 1991; Koch & Greenfield, 2007).

Figure 7.1 Portrait of René Descartes. The French philosopher René Descartes (1596-1650) was a proponent of dualism, the theory that the mind and body are two separate entities. Psychologists reject this idea, however, believing that consciousness is a result of activity in the brain, not separate from it.

The study of consciousness plays an important role in many important psychological theories. Freud’s personality theories differentiated between the unconscious and the conscious aspects of behaviour. His concept of subconscious accounts for things like memory and motivations that remain outside of the realm of consciousness (Biswas-Diener & Teeny, 2019). As discussed in Chapter 2, the idea of preconscious refers to information that we could pay attention to if desired, and where memories are stored for easy retrieval.

Consciousness is also important to the fundamental psychological question regarding the presence of free will. Although we may understand and believe that some of our behaviours are caused by forces that are outside our awareness (i.e., unconscious), we nevertheless believe that we have control over, and are aware that we are engaging in, most of our behaviours. To discover that we have, or someone else has, engaged in a complex behaviour, such as driving in a car and causing severe harm to others, without being at all conscious of these actions, is so unusual as to be shocking. And yet psychologists are increasingly certain that a great deal of our behaviour is caused by processes of which we are unaware and over which we have little or no control (Libet, 1999; Wegner, 2003).

Our experience of consciousness is functional because we use it to guide and control our behaviour, and to think logically about problems (DeWall, Baumeister, & Masicampo, 2008). Consciousness allows us to plan activities and to monitor our progress toward the goals we set for ourselves. And consciousness is fundamental to our sense of morality — we believe that we have the free will to perform moral actions while avoiding immoral behaviours.

Present-day psychologists distinguish between automatic (unconscious) and controlled (conscious) behaviours and between implicit (unconscious) and explicit (conscious) memory (Petty, Wegener, Chaiken, & Trope, 1999; Shanks, 2005).  Awareness operates on two levels and humans fluctuate between the high and low thinking states. Low awareness of subtle and even subliminal influences can become conscious as a result of cues or stimulus of significant meaning. High awareness refers to our consciousness of what is going on around us. Mindfulness is a state of heightened awareness, focus, and evaluation of our thoughts. Attention is what William James (1890) referred to as a concentration of consciousness. It is a mental resource that can be vigilant and sustained or divided and selective (Biswas-Diener & Teeny, 2019).

Priming studies aim to activate certain concepts and associations in people’s memory below conscious awareness in order to understand the effect on subsequent behaviour. Researchers engage the implicit associations test (IAT) to study unconscious motives and beliefs.  The Flexible Correction Model suggests that humans have an ability to correct or change beliefs and evaluations that have been influenced or biased by an undue, outside source.

Because the brain varies in its current level and type of activity, consciousness is transitory. If we drink too much coffee or beer, the caffeine or alcohol influences the activity in our brain, and our consciousness may change. When we are anesthetized before an operation or experience a concussion after a knock on the head, we may lose consciousness entirely as a result of changes in brain activity. We also lose consciousness when we sleep.

Sleep is unique because while we lack full awareness in this state of consciousness, the brain is still active. Sleep serves the function of mental and physical restoration. Dreams are an interesting aspect of sleep. Theories suggest that dreaming is our nonconscious attempt to make sense of daily experience and learning (Biswas-Diener & Teeny, 2019).  According to Freud, dreams represent troublesome wishes and desires.

Hypnosis is a mental state characterized by reduced peripheral awareness (Kihlstrom, 2003). It is usually induced by a procedure known as hypnotic induction, which consists of heightened suggestibility, deep relaxation, and intense focus (Nash & Barnier, 2008). Sensory deprivation is the intentional reduction of stimuli affecting one or more of the five senses, with the possibility of resulting changes in consciousness. Meditation refers to techniques in which the individual focuses on something specific, such as an object, a word, or one’s breathing, with the goal of ignoring external distractions, focusing on one’s internal state, and achieving a state of relaxation and well-being. A trance state involves a dissociation of the self where people are said to have less voluntary control over their behaviors and actions.

In some cases, consciousness may become aversive — for instance, when we become aware that we are not living up to our own goals or expectations, or when we believe that other people perceive us negatively. In these cases, we may engage in behaviours that help us escape from consciousness, through the use of psychoactive drugs for example (Baumeister, 1998).

Some substances can have a powerful effect on perception and on consciousness. A psychoactive drug is a chemical that changes our states of consciousness, and particularly our perceptions and moods. Opioids are chemicals that increase activity in opioid receptor neurons in the brain and in the digestive system. Opioids produce euphoria, analgesia, slower breathing, and constipation. Hallucinogens are substances that alter a person’s perceptions, often by creating visions or hallucinations that are not real. Depressants reduce the activity of the CNS and slow down the body’s physiology and mental processes.  Stimulants speed up the body’s physiological and mental processes and operate by blocking the reuptake of dopamine, norepinephrine, and serotonin in the synapses of the CNS. Stimulants are highly addictive, and we will discuss why in terms of their effect on the brain further along in this chapter.

Even when we know the potential costs of using drugs, we may engage in using them anyway because the rewards from using the drugs are occurring right now, whereas the potential costs are abstract and only in the future. And drugs are not the only things we enjoy or can abuse. It is normal to refer to the abuse of other behaviours, such as gambling, sex, overeating, and even overworking, as “addictions” to describe the overuse of pleasant stimuli.

Image Attributions

Figure 7.1: Portrait of René Descartes by André Hatala, (é_Descartes.jpg) is in the public domain.


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