lecture6

States of Consciousness
ZahbiaSarfrazLahore School of Economics
PSYCHOLOGY – SSC 210
A state of awareness of:The sights and sounds of the outside worldOur feelingsOur thoughtsOur own consciousnessConsciousness is:PersonalCan be selectiveContinuous and ever-changing
What isConsciouness?
Wide awake and thinkingDaydreamingHypnosisHigh on drugsDreaming
Common States of Consciousness
Dividedconsciousness: the splitting off of two conscious activities that occursimultaneouslyThe ability to focus awareness on a single stimulus to the exclusion of otherstimuli
Divided Consciousness
Unconscious mind: mental processes that occur without conscious awarenessCocktail party phenomenon- you are in a room with more than one person talking and you mostly listen to one person tuning out other voicesEvidence that other noises reach your brain even though we are never consciously aware of it
The Unconscious Mind
Andrew Mathews and ColinMaclead(1986):Participants listen to 2 messages – 1 in each earphoneAsked to ignore messages from 1 & repeat the otherNonthreatening words (friend) and threatening words (e.g. assault) presentedAsked to keep eye on screen & press key when the word ‘press’ appeared on screenResults: when threatening word presented in the earphone that was being ignored, subjects pressed key less quickly than otherwiseConclusion: ignored words were being processed without conscious awareness
The Unconscious Mind
5 stages of sleepFirst four stages are non-REMFifth and final stage is REMStage 1Brain activity: betato alpha to theta (by end of stage)Hypnagogic state: relaxed state of dreamlike awareness between wakefulness and sleep‘twilight’ state: neither daydreaming nor dreamingMyoclonia: abrupt movement sometimes occurs during this state; sleeper experiences a sense of fallingLasts about ten minutesBegin to lose voluntary control over body movements, sensitivity to outside stimuli diminishes, thoughts less bound by reality.
Stages of Sleep
Stage 2EEG pattern: even slower and larger waves; periodic short bursts of activity called ‘sleep spindles’More relaxedRolling eye movements stopLess easily disturbedIf someone makes noise, brain will register but probably will not wake upAbout 20 minutes
Stages of Sleep
Stage 3 & 4Hard to distinguish from each other - differ only in degreeEEG: onset of very slow waves with large peaks – ‘delta waves’ – last for about 30 minutesSleep walking or talking occurs during thisstageAfter stage 4 – go back to 3 and 2 and then go to stage 5
Stages of Sleep
Stage 5EEG: short, high frequency beta waves (similar to those when you are awake)Blood flow to the brain increasesBreathing and pulse rates speed upMuscles are totally relaxedRapid eye movements: eyelids shut but eyeballs moving frantically back and forthSubjects sleeping awakened during:- non REM stages report dreams about half the time- REM stages report dreams about 80% of the timeREM dreams are visual, vivid, detailed andstorylike.
Stages of Sleep
Restorative theoriesSleep rejuvenates usAmount of slow wave sleep depends on how long we’ve been awakeCircadian theoriesEvolutionarily, it has survival valueREMsleep plays an essential role in consolidation of newly learned information from the day before
Why do we sleep?
Dreams are electrochemical events that involve the brainstem, the cortex and the eyesWhy do we have dreams?What, if anything, do they mean?Can you guess the three most common themes?
What are Dreams?
Common themesFallingBeing chased or attackedRepeatedly trying but failing to do something
Content of Dreams
What influences the dreams we have?Day residue: events and concerns about the person’s waking lifeStimulus incorporation: stimuli occurring during sleep incorporated directly or in altered formThe dreamer himself: lucid dreaming
Content of Dreams
Why do we dream?
Wish fulfillment (Freud)Manifest contentLatent contentActivation-synthesis (Hobson &McCarley)Activation: random neural signals firing in the brainstem that spread up to the cortexSynthesis: the brain then creates images and stories in an effort to make sense out of these random signalsSo who’s right?
InsomniaSleep-onset insomniaEarly-awakening insomniaNarcolepsyPerson suddenly falls asleep during activities usually performed when fully awakeSleep apneaThe sudden interruption of breathing during sleep
Sleep Disorders
Common characteristics:Distortion of perceptionIntense positive emotionsIllogicalIndescribableCan you suggest other characteristics?
Altered States of Consciousness
MeditationA method of focusing concentration away from thoughts and feelings and generating a sense of relaxingMindfulnessThe state of focusing conscious awareness completely on what is going on at the present momentHypnosisAltered state of consciousness in which the individual is highly relaxed and susceptible to suggestionsDepersonalizationThe perceptual experience of one’s body or surroundings becoming distorted or unreal
Altering Consciousness
Psychotropic drugsVarious classes of drugs that alter conscious experience.Induce changes in thinking, perception and behavior by affecting neural activity in the brainFour general categoriesDepressantsStimulantsHallucinogensInhalants
Drugs and Altered Consciousness
Reduce the activity of inhibitory centers of the central nervous systemCreate a sense of relaxationReduce inhibitionsE.g. alcohol, sedatives, valium, morphine
Depressants
Activate motivational centersReduce activity in inhibitory centers of the central nervous systemProvide a sense of energy and well beingE.g. caffeine, cocaine, MDMA (ecstasy), nicotine
Stimulants
Most powerfully alters consciousnessAlter perceptual experienceLarge doses lead to vivid hallucinationsE.g. LSD
Hallucinogens
Common chemicals that are put to dangerous use when inhaled to produce feelings of intoxicationE.g. gasoline, glue, nail polish remover
Inhalants