PSY100-consciousness10

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Introduction to Psychology

Consciousness

Consciousness

• William James (1890): – Consciousness is a constantly moving stream of thoughts, feelings, and emotions • Consciousness can be viewed as our subjective awareness of mental events • Functions of consciousness: – Monitoring mental events – Control: consciousness allows us to formulate and reach goals • Consciousness may have evolved to direct or control behavior in adaptive ways

Cortex and Consciousness

• The dorsolateral prefrontal cortex is activated during conscious control tasks – Subjects asked to name the ink color in the Stroop task below have difficulty when the word name and color are different – This color-naming task was associated with activation of the dorsolateral prefrontal cortex

Attention

• Our conscious awareness is limited in capacity and we are aware of only a small amount of the stimuli around us at any one time • Attention refers to the process by which we focus our awareness • Three functions of attentional processes: – Orienting function toward the environment – Control of the content of consciousness • I will think about this issue but not that one… – Maintaining alertness

Subliminal Perception

• Notion that brief exposure to sub-threshold stimuli can influence awareness • Study: subjects are shown aggressive (A) or positive (B) stimuli – and then rate a neutral stimulus (C) – Subjects shown panel A first subsequently rated the boy in panel C more negatively (Figure adapted from Eagle, 1959)

Unconscious Cognitive Processes

• Information-processing view can be extended to analyses of unconscious processes • Notion is that many brain mechanisms operate in parallel – Some of these mechanisms operate outside of the level of consciousness • Functional significance of unconscious mechanisms: – Are efficient and rapid – Can operate simultaneously – Operate in the absence of consciousness?

Neurology of Consciousness

• Consciousness is distributed throughout the brain – Hindbrain and midbrain are important for arousal and for sleep – Damage to the reticular formation can lead to coma – Prefrontal cortex is key for conscious control of information processing

Sleep and Dreaming

• Behavioral characteristics of sleep – Minimal movement – Stereotyped prone posture – Require a high degree of stimulation to arouse organism • Physiological characteristics of sleep – Brain wave activity (seen in the EEG) – Paralysis of muscles (seen in the EMG) – Cardiovascular changes (alternating cycles of arousal)

Function of Sleep

• Memory consolidation • Energy conservation • Preservation from predators • Restoring bodily functions – Sleep deprivation can alter immune function and lead to early death – Sleep deprivation can also lead to hallucinations and perceptual disorder

EEG Stages of Sleep

(Figure adapted from Cartwright, 1978)

REM Sleep

• Characteristics of REM sleep – Presence of rapid-eye-movements – Presence of dreaming – Increased autonomic nervous system activity – EEG resembles that of awake state (beta wave) – Motor paralysis (except for diaphragm)

Dreaming

• Psychoanalytic view: Dreams represent a window into the unconscious – The latent content (meaning) can be inferred from the manifest content (the actual dream) • Cognitive view: Dreams are constructed from the daily issues of the dreamer • Biological view: Dreams represent the attempt of the cortex to interpret the random neural firing of the brain during sleep

Dreaming

• Evolutionary view: on-line threat simulation and behavioral rehearsal system • Virtual reality training center • Problem solving Perspective

Lucid Dreaming

1) Dream journaling – note dream signs 2) Reality testing 3) Relaxation techniques 4) Pre-sleep suggestions 5) Sleep in a different place or position

Lucid Dreaming Suggested Readings

Garfield, P. (1974). Creative Dreaming. New York: Ballantine.

LaBerge, S. (1985). Lucid Dreaming. Los Angeles: J. P. Tarcher.

LaBerge, S. & Rheingold, H. (1990). Exploring the World of Lucid Dreaming. New York: Ballantine.

Zadra, A.L., Donderi, D.C. & Pihl, R.O. (1992) Efficacy of lucid dream induction for lucid and non-lucid dreamers. Dreaming, 2, 85-97.

Zadra, A.L., & Pihl, R.O. (1997). Lucid dreaming as a treatment for recurrent nightmares. Psychotherapy Psychosomatics, 66, 50-55.

Altered States of Consciousness

• Changes in consciousness can be brought on by – Meditation – Hypnosis – Drug ingestion – Religious experiences

Meditation

• Focused Breathing • Physiological responses • Cognitive responses • Attentional Focus • Quieting the mind (self-talk) • Alpha waves (EEG)

Hypnosis

• Hypnosis is a state of consciousness characterized by – Deep relaxation – Suggestibility • Effects observed during hypnotic state: – Age regression – Change in pain perception – Ability to recall memories into consciousness • Dissociation?

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