Chapter 58: States Of Consciousness Flashcards
What is the nature of consciousness
Consciousness is defined as awareness of all sensation thoughts and feelings at a particular time. To be conscious means to be aware and spend most time in waking consciousness which is a state of clear organised alertness.
How is consciousness examined
Done so in terms of level of arousal which can vary from low to high which aren’t seperate but occurs in a continuum of arousal from low to high.
At the lowest level one is unconscious and as you increase arousal they move to deep sleep then light sleep to drowsiness and then wakefulness and at higher level person is highly alert where intense emotional excitement characterises highest state of arousal
Explain nature of sleep
It isn’t a lack of consciousness as brain maintain sleep shown by physiological measurements of brain activity with an electroencephalogram EEG that show different brain waves according to amplitude and frequency.
Delta waves have high amplitude and frequency 0.5-3gz. drowsy and falling asleep
Theta waves have slightly lower and irregular amplitude and frequency 4-8hz
Alpha waves have medium amplitude and frequency of 8-12hz. Awake and relaxed.
Beta waves have low amplitude and frequency of 13-30hz. High level of arousal
What is s-sleep
Wave pattern are Synchronised ( high amplitude and low frequency called restful sleep.
Phase 1 sleep is state of drowsiness or light sleep where EEG shows alpha and Delta waves (3 5-7.5hz) and person can be easily aroused but body is relaxed with slow heart beat and deep regular breathing.
Phase 2: sleep follows approx 10 Min later is a deeper sleep where wave frequency are mixed.
Phase 3: sleep is deep where EEG shows Delta waves person is very relaxed and autonomic activity slows down
Phase 4: sleep is very deep more than half of EEG is Delta waves and hard to rouse person now but if woken are confused slurred speech and poor motor co ordination
Describe D- sleep
Resynchronized wave pattern ( low amplitude and high frequency) sleep where dreams occur.
REM rapid eye movement occurs even though eyes are shut. Muscle tone is low and sleeper is unable to move but when woken are instantly awake and know what’s happening around them.
What are the function of sleep
Believed sleep is essential for normal functioning and sleep deprivation is a form of stress which has negative effect on concentration and coping ability which can also effect physical and mental health.
According to cognitive theory REM sleep allows brain to withdraw from outside world and reorganize info collected to be organised more meaningfully.
The neurobiological perspective believe that cortex holds large interconnections which holds that memory info is encoded in these networks. When aspects of network is triggered by stimulus related info is remembered. When overload of info happen network don’t function well.
REM sleep suggested as mechanisms for cleaning up networks by deleting unnecessary info and that dreams are info brain wants rid of
Explain what insomnia is
Term describing inability to sleep which may refer to difficulties falling asleep or waking in the middle of the night unable to sleep again.
What is narcolepsy
Term used for symptoms of sleep that occurs during wakefulness. A narcoleptic attack is an overwhelming need to sleep and can happen at anytime which lasts a few minutes.
What is catalepsy
A sudden collapse when person is awake but unable to move. Triggered by intense emotional experience or sudden movement. Another symptom being sleep paralysis that occurs before falling asleep or waking up. Person is awake but unable to move and ends when touched or called.
What is sleep apnoea
Refers to condition of breathing difficulties during sleep where you wake up grasping for breath and then falling back asleep.
What is hypnosis
It’s a situation in which people’s behaviour is involuntary or hypnotic and occurs because of increased suggestibility in context of special relationship between person and hypnotist.
What can hypnosis achieve
Produces relaxation concentration and temporary changes in behaviour. It can also decrease pain by altering emotional component of pain.
Posthypnotic suggestion refers to suggestions to do or experience something in particular after coming out of hypnotic state. Behaviour change may persist needing long term help.
What can’t hypnosis do
It cant give you powers or make you do things you couldn’t do while conscious.
Dissociation means hypnosis splits consciousness into 2 streams one communicating with hypnotist and external world and other with person’s inner thoughts
What are stimulants and their effect?
Drugs that increase alertness boost energy and activities while producing pleasant feeling. They activate motivational centre and reduce activity inhibitory centres of brain.
Give examples of stimulants
Amphetamine: increases release of dopamine in brain. They work by preventing neurons from reabsorbing dopamine they release and effects of dopamine are prolonged. They increase activity at norepherphine and serotonin synapses. They increase heart rate blood pressure and body temperature.
Cocaine: stimulant increases heart rate making people excited and interferes with sleep. Cocaine works by decreasing activity of neurons that inhibit other neurons by slowing the neurons that suppose to inhibit others it results in stimulated behaviour.
Caffeine: blocks a chemical that inhibits glutamate synapses. It increases activity of glutamate which is excititory transmitter.
Nicotine: increases wakefulness and arousal ( stimulating acetylcholine receptor) it can cause stress and tension to increase.
