Consciousness what is consciousness ? Different concepts of consciousness why do we sleep? Why do we dream? Sleep stages and EEG changes Altered states of consciousness Substance abuse

Consciousness Sensory awareness of environment. State of being awake and aware of what

is going on around you Clear perception Proper orientation Attention and concentration Comprehension Ability to respond and communicate

Consciousness- Consciousness as direct inner awareness Direct inner awareness : Knowledge of ones own thoughts, feelings, and

memories without use of sensory organs. Sigmund Freud’s concept :

Unconscious : ideas and feelings that are not available to awareness by simple focusing of attention Preconscious : ides and feelings that are not in awareness but can be brought into awareness by focusing ones attention Conscious : Thoughts and feelings, we are aware of.

Why Do We Sleep? Two main theoretical approaches : Recuperation theories suggest that wakefulness

somehow disturbs some aspect the body’s balance or homeostasis and some aspect of sleep helps to restore it

Circadian theories suggest that a neural mechanism has developed to encourage sleep during those periods of the day when an animal is least active to conserve energy and to make them less vulnerable during this time.

Dreams We dream in color and/or Black & White Dreams are more frequently disturbing and unpleasant rather

than pleasant. The most common setting for dreams is indoors rather than

outdoors. Dreams usually involve motion and action. Can increase awareness with recordings or immediate writing

of them to a note pad. 1st dream is about 10 minutes, they increase length over time

last one is about 60 minutes. They must be close to REM to remember them.

Why do we dream?

Freud - Road to unconscious, symbolic representations of wishes and fears we cannot express in consciousness. Manifest Content - obvious but superficial meaning of dreams Latent Content - true meaning of dreams

Why do we dream?Why do we dream?

Activation-Synthesis Theory (Hobson & Activation-Synthesis Theory (Hobson & McCarley, 1977)McCarley, 1977)1. Brainstem bombards higher brain centers 1. Brainstem bombards higher brain centers with random neural activitywith random neural activity2. Cerebral cortex interprets activity and 2. Cerebral cortex interprets activity and creates a dream.creates a dream.

Why do we dream? Information Processing (Cartwright)-

.Dreams are an Extension of Waking Life and that in our dreams we express our emotional concerns and most private thoughts.

 

Sleep disorders InsomniaInsomnia: Chronic difficulty in falling : Chronic difficulty in falling

asleepasleep NarcolepsyNarcolepsy: Sudden, uncontrollable : Sudden, uncontrollable

sleep attackssleep attacks Sleep apneaSleep apnea: Breathing stops and : Breathing stops and

restarts during sleeprestarts during sleep SleepwalkingSleepwalking

Stages of Sleep During the various stages of sleep, the

brain emits waves with different frequencies (number of waves per second) which can be recorded in EEG.

AWAKE: --beta waves , high frequency, low

amplitude JUST BEFORE SLEEP: alpha waves, medium frequency, medium

amplitude

Stages of sleep NON RAPID EYE MOVEMENT SLEEP (NREM): Stages of sleep 1 through 4. Stage 1 : low frequency, some theta waves

(higher amplitude) Stage 2—4 : lower frequency, higher amplitude.

Delta waves at stage 4. Very low frequency and high

amplitude RAPID EYE MOVEMENT SLEEP (REM) : A stage of sleep characterized by rapid eye

movements, which have been linked to dreaming. Return to awake like condition

Brain WavesBrain Waves

Stage 3

Awake

Stage 1

Stage 2

Stage 4

Stages of Sleep

REM sleep Slow wave/non-REM sleep

Eye movement rapid Slow/no eye movement

Loss of core muscle tone (i.e. paralysis) Muscle tonus moderate

EEG desynchronised EEG synchronised

Cerebral energy use equal to or higher than waking

Cerebral energy use below that of waking

Increased ANS activity ANS unchanged

Penile/clitoral erection No genital activity

"Typical" dream contact No Dreams

Altered states of consciousness Hypnosis A condition in which people appear to be highly

suggestible and behave as though they are in a trance.

Meditation Thinking deeply Rituals and exercises or activities that alter the

normal relationship between the person and his or her environment.

Substance abuse and dependence

Substance Abuse : Persistent use of a substance even though it is causing problems in meeting the demands of life

Tolerance : Habituation to a drug, with the result that increasingly higher doses of the drug are needed to achieve similar effects

Substance dependence : Normal functioning of body and mind depends on regular intake of drug

Substance withdrawal Syndrome : A characteristic cluster of symptoms that results from sudden decrease in an addictive drug level of usage

Common drugs of abuse Opiates Alcohols Cannabis Stimulants Tranquilizers Nicotine Caffeine Hallucinogens