What is consciousness?

• Three positions on the nature of consciousness

• What we know about consciousness

• The ability to communicate with ourselves symbolically gives rise to consciousness (Direct inner awareness)

The Meanings of Consciousness

Sensory Awareness- Knowledge of the environment through perception of sensory stimulation

Selective Attention- The process that controls our awareness of particular categories of events in the environment

• Controlling Attention• Broadbent (1958) – The brain mechanisms

responsible for consciousness processing have a limited capacity

• Selective Attention – serves as a gatekeeper

Auditory Information• Cherry (1953)- devised a test of selective attention

called dichotic listening, using a process called shadowing.

Exceptions: A person’s name and sexually explicit words.

• Von Wright, Anderson, and Stenman (1975)-information to the unattended ear can produce implicit memories

• McKay (1973)- information to the unattended ear can influence verbal processing even when the listener is not conscious of this information.

• The cocktail-party phenomenon- our ears receive a jumble of sounds, but we are able to pick out the ones we want, stringing them together in a meaningful message and ignoring the rest.

Visual Information

Location of the Information• Sperling (1960)- first to demonstrate the

role of attention in selectively transferring visual information into verbal short-term memory (iconic memory)

• Posner, Snyder, and Davidson (1980)- selective attention can affect the detection of visual stimuli

Nature of the Information

• Rock and Gutman (1981)- people can pay attention to one of two shapes, even when the shapes overlap.

Brain Mechanisms involved in Selective Attention

That some components of the brain’s sensory system are temporarily sensitized, which enhances their ability to detect particular stimuli, is one possible explanation for selective attention.

Biology and Culture

• Control of Consciousness - A craving for at least occasional changes in consciousness seems to be a widespread trait among members of our species

• Means to alter consciousness – drugs, fasting, chants, dancing, religious rites, and meditation

Techniques for withdrawing attention

• The goal of most meditation exercises is to remove attention from all stimuli – to think about absolutely nothing.

• By concentrating on an object, a sound, or a repetitive movement, we can learn to ignore other stimuli.

• Withdraw of attention appears to have two primary goals: to reduce verbal control over nonverbal functions of the brain and to produce a heightening of awareness and an increase in attention.

Increasing and Dishabituating Attention

• The easiest way to do this is to encounter novel stimuli

• Do things differently• Do something

dangerous• Remove yourself

temporarily from your everyday environment

Consciousness and The Brain

• Brain dysfunctions

• Isolation Aphasia – A language disturbance that includes an inability to comprehend speech or to produce meaningful speech, but also includes the ability to repeat speech and to learn new word sequences.

Brain Dysfunctions

• Visual Agnosia – The inability to recognize the identity of an object visually

Brain Dysfunctions

• The split-brain syndrome – people with severe epilepsy undergo an operation that severs their corpus callosum, abolishing the direct connections between the cortex of the two hemispheres

Hypnosis (or “You are now a chicken!”)

• Hypnosis – A specific and unusual form of verbal control that apparently enables one person to control another person’s thoughts, behavior, and perceptions

• Discovered by Franz Anton Mesmer

Hypnosis

• The Induction of Hypnosis

• Hypnotized people have a high degree of suggestibility

Hypnosis

• Posthypnotic suggestibility – A person who is given instructions under hypnosis and follows these instructions after returning to a non-hypnotized state.

• Post-hypnotic amnesia – A failure to remember what occurred during hypnosis; induced by suggestions made during hypnosis.

Hypnosis

• Miller, Hennessy, and Leibowitz (1973) – used the ponzi illusion to test the effects of hypnotically induced blindness

Evolutionary Theory of Hypnosis

• Barber (1979) – Certain aspects of hypnosis are related to events that occur in everyday life

• Hypnosis as a social role

Susceptibility to Hypnosis

• Who gets hypnotized?

• Personality types

• The ability to produce vivid mental images, and a capacity for becoming involved in imaginative activities, increases chances to become hypnotized

• Preference for right-hemisphere tasks

Hypnotic Coercion

• Can people be coerced into doing something dangerous or immoral?

• Some say “yes” and some say “no”

• This issue will probably remain unresolved

Sleep

• Sleep is a state of altered consciousness

• We spend one-third of our lives sleeping

• The evidence for why we sleep is still unclear

Stages of Sleep

• Awake –Beta activity, Alpha Activity

• Stage 1 – Theta activity

• Stage 2, Stage 3

• Stage 4 – Delta activity

• REM – Theta activity and Beta activity

Functions of Sleep (why do we sleep?)

• Sleep – A universal behavior

• Deprivation studies have not obtained persuasive evidence that sleep is needed to keep the body functioning normally

• Sleep may be required for normal brain functioning

Functions of Dreams

• Two approaches – psychological and psychobiological

• Symbolism – Freud’s theory and Hall’s theory

• Hobson’s explanation (1988)

• Sleep Development

Sleep Disorders

• Insomnia – Affects 20% of the population at some time

• Sleep Apnea- “without breathing”• REM sleep behavior disorder – The absence of

paralysis that normally occurs during REM sleep• Cataplexy – A biological disorder, where a person

collapses, becoming temporarily paralyzed but not unconscious

Sleep Disorders

• Sleepwalking

• Sleep talking

• Night terrors

• Enuresis (bed-wetting)

Conclusion of Presentation

Have A Great Weekend!