VCE Psychology Unit 4 AOS 1

Criticisms of the Evolutionary theory

. Evolutionary theory does not explain why we MUST have sleep . the assumption that sleeping is a way to stay safe - the loss of awareness during sleep may actually make the animal more vulnerable to predators and less likely to be able to respond to danger

Disadvantages of sleep diaries

. a subjective measure that is open to interpretation

Examples of depressants

. alcohol . barbituates . benzodiazepines . opioids . heroin . morphine . codeine

Consciousness is

. an experience . personal (subjective) . selective (can choose to attend to certain things and ignore others) . continuous . constantly changing

Disadvantages of physiological measurements

. cannot describe the person's private and personal conscious experience (thoughts and experience) . changes in physiological events may be due to other reasons, not a change in state of consciousness

Types of responses recorded from video monitoring

. changes in posture or body position . amount of 'tossing and turning' . sleep-related breathing problems . what happens when awakening from a nightmare or night terror . behaviours associated with sleepwalking

Disadvantages of video monitoring

. data can be open to interpretation so requires clear definition for a specific behaviour . may miss important events if only considering still photographs every few seconds/minutes. Otherwise, lots of information to sift through . participant's behaviour may be blocked from view of the camera

Advantages of sleep diaries

. give an important insight into actual thoughts and feelings of participants

In studying an individual's state of consciousness, researchers typically rely on

. information provided by the individual (e.g. self-reports) . behaviour that is demonstrated (e.g. responses during experimental research) . physiological changes that can be measured (e.g. recording brain activity)

Advantages of video monitoring

. insight into observable behaviour during sleep . can be undertaken in sleep laboratory or normal bed (natural setting) . researchers can continuously monitor the behaviour, either at the time of collection or at a later stage or both . data can be recorded alongside the physiological measurements at the time

Contents of consciousness

. internal sensations, e.g. breathing . external surroundings, e.g. perceptions of where you are, what you see, hear, feel or smell . your self as the unique person having these experiences . memories of personal experiences . comments you make to yourself . your beliefs and attitudes . your plans for activities later in the day

Changes in a person's psychological state

. levels of awareness . controlled and automatic processes . content limitations . perceptual and cognitive distortions . emotional awareness . self-control . time orientation

Other techniques to investigate consciousness

. measurement of speed and accuracy on cognitive tasks . subjective reporting of consciousness . sleep diaries . video monitoring

Advantages of physiological measurements

. most objective . most reliable means of indicating different states of consciouness

Restorative theory suggest that sleep

. repairs and replenishes the body and prepares it for the next day . enhances mood . activates growth hormone . increases immunity to disease and increases alertness upon waking . consolidates memories

Role of attention

. the more attention, the higher the degree of awareness and vice versa . NWCs involve more awareness and therefore, more attention than ASCs . internal VS external . intentional VS unintentional

Type of information recorded in sleep diaries

. the time when trying to fall asleep . the time when it is believed sleep onset occurred . the number, the time and the length of awakenings during sleep . the time of waking up in the morning . the time of getting up after waking in the morning . how well rested the individual feels upon awakening . how sleepy the individual feel at different times during the day

Variables that effect the potential effects of drugs

. the type of stimulant or depressant that is taken . the dose (amount) and potency (strength) . personal characteristics of the individual (e.g. body weight, physiology, sex, age, health and wellbeing, prior use, personality, mood, expectations) . method of administration (e.g. oral, injection, inhalation, skin patch) . when administered (e.g. daytime or night time before sleep) . whether other drugs are also taken . context (e.g. alone or with others, social or medical situation)

Theories about the purpose of sleep

1. Evolutionary theory 2. Restorative theory

Dawson & Reid (1997)

40 participants in a repeated measures experiment with counterbalancing . Condition 1 - participants were kept awake for 28 hours (from 8.00 am to 12 noon the following day) . Condition 2 - they were asked to consume 15 grams of alcohol every 30 minutes until their BAC reached 0.10%.

B.A.T.D

Beta Alpha Theta Delta

D.A.R.E

Detects, Amplifies and Records Electrical activity

Electrical activity of the brain

Different brain wave patterns are associated with different states of consciousness . brain waves vary in frequency and amplitude

Depressants effect on brain activity/waves

INCREASES . Alpha . Theta . Delta DECREASES . Beta

Stimulants effect on brain activity/waves

INCREASES . Beta DECREASES . Alpha . Theta . Delta

Examples of stimulants

MILD . caffeine (e.g. coffee, tea, chocolate, cola, energy drinks and some non-prescription medications) . nicotine (e.g. cigarettes and other tobacco products) STRONG . amphetamines . ice . cocaine . ecstasy

Extraneous variables in Dawson & Reid (1997)

MOTIVATION and/or MOOD . evidence that sleep deprivation and alcohol consumption influence and are influenced by our mood state . generally, sleep deprivation results in a negative mood state (e.g. irritability, short-tempered) and alcohol consumption results in either a positive or negative mood state, depending on such variables as the amount of sleep deprivation or alcohol, the individual and the context . in turn, our mood state influences our conscious experience and can either enhance or impair concentration and cognitive performance . this can undermine performance on a variety of simple and complex cognitive tasks In sum, sleep deprivation, alcohol, cognition, concentration and mood are intertwined and may interact in complex ways in influencing conscious experience

Restorative theory differentiates between REM & NREM

NREM is believed to be important for restoring and repairing the body . physical growth, tissue repair, etc.

Stages of sleep

NREM stage 1 (lightest) NREM stage 2 NREM stage 3 NREM stage 4 (deepest) REM NREM and REM sleep periods alternate throughout the night in a cyclical way, with one following the other

Self-control

NWC . able to coordinate a sequence of movements and fine motor skills ASC . generally unable to coordinate movements; inhibitions are often lost (although in some ASCs such as hypnosis people may gain more control over habits) . limited ability to complete controlled processes and some automatic processes are impaired

Perceptual and cognitive distortions

NWC . aware of our thoughts which are clear, logical and meaningful . able to complete controlled and automatic processes . perceptions are accurate ASC . Perception: one of two effects on the senses . it either makes them more receptive to external stimuli . dulls them to such an extent that some sensations are not experienced at all . may experience hallucinations . may reduce or heighten experience of pain. . Cognition: thinking may be illogical; individuals may experience difficulty problem solving and decision making . Memory: unable to remember information accurately e.g. gaps, blackouts

Emotional awareness

NWC . experience emotions that are appropriate and are aware of feelings ASC . emotions may be heightened or dulled, and may not be appropriately expressed

Time orientation

NWC . time is perceived as moving at a normal rate ASC . estimation of time is distorted . time may appear to move faster or slower

Content limitations

NWC . able to control thoughts, and selectively restrict the content of consciousness ASC . individuals have less control over the material that enters their consciousness e.g. strange illogical things happen in dreams

Level of awareness

NWC . we are aware of internal thoughts and feelings and of external stimuli. ASC . low level of awareness of internal and external environments.

Degrees of NWC

NWC is not one single state, as there are varying levels or 'degrees' of awareness we shift between when we are awake

Consciousness continuum

TOTAL AWARENESS . Focused attention . Normal wakefulness DIVISION BETWEEN NORMAL WAKING CONSCIOUSNESS AND ALTERED STATES OF CONSCIOUSNESS . Daydreaming . Meditative state . Hypnotised . Asleep . Anaesthetised . Coma COMPLETE LACK OF AWARENESS

Controlled vs Automatic processes

Type of attention - Controlled: selective - Automatic: divided Speed of processing - Controlled: slower - Automatic: faster Task complexity - Controlled: high - Automatic: low Easily multitask - Controlled: no - Automatic: yes

Evidence for the Evolutionary theory

VULNERABILITY TO PREDATORS . larger grazing/prey animals like zebras/gazelles sleep only for short periods as they are more vulnerable to attack (can't hide easily, climb trees etc.) so are safer awake . predatory animals (e.g. lions) sleep much more . smaller animals like mice can hide easily from predators, so they sleep for longer periods . humans cannot see in the dark, so sleep at night AVAILABILITY OF FOOD . smaller animals like possums/bats eat less food and need less time to find/digest it - they don't need to be awake for long periods so sleep longer

Attention

a concentration of mental activity that involves focusing on a specific stimulus while ignoring and therefore excluding other stimuli . a measure of awareness to distinguish between different states of consciousness

Psychological construct

a concept that is 'constructed' to describe specific 'psychological' activity, or a pattern of activity, that is believed to occur or exist but cannot be directly observed

Electroencephalograph (EEG)

a device that detects, amplifies and records the electrical activity of the BRAIN in the form of brainwaves

Biological rhythms

a naturally occurring pattern of cyclic changes in a bodily function or state that repeats itself over time

Naturally-occurring ASCs

a normal part of our lives and occur naturally in the course of our everyday activities without the need for any aid e.g. sleep, daydreaming & dreaming

NREM stage 2

a period of light sleep, and during the first cycle some researchers identify this as the point at which someone can be said to be truly asleep PREDOMINATELY theta waves PHYSIOLOGICAL CHANGES include body movements lessen, breathing becomes more regular, blood pressure and temperature continue to fall, heart rate is slower and eye movements stop ACCOUNTS FOR about 45 to 55% of the total sleep episode

BETA waves

a predominantly beta brain wave pattern is associated with alertness and intensive mental activity during NWC . high FREQUENCY (fast) and low AMPLITUDE (small) brain waves

THETA waves

a predominantly theta brain wave pattern is most commonly produced when we are very drowsy, such as when falling asleep or just before waking . medium FREQUENCY and some high-AMPLITUDE (large) waves mixed with some low-AMPLITUDE (small) waves

Sleep

a regularly occurring state of consciousness that typically occurs spontaneously and is primarily characterised by a loss of conscious awareness . Sleep is a CIRCADIAN RHYTHM

NREM (non-rapid eye movement)

a relatively inactive brain in a body that can move

Sleep diaries

a self-reported record of an individual's sleep and waking time activities, usually over a period of several weeks . subjective . usually used in conjunction with polysomnographic tests

Alcohol

a very commonly used depressant. Initially, it seems to stimulate the CNS but the major effect is inhibitory Consumption of alcohol affects . mood . thought . perception . attention . judgement . memory . sleep . coordination alcohol dampens the motor and sensory brain areas and makes perceptual judgements, co-ordination and balance more difficult

Controlled processes

actions that involve conscious, alert awareness and mental effort focused on achieving a particular goal (serial) e.g. playing tetris, learning to drive

Automatic processes

actions that require little conscious awareness or mental effort, minimal attention, and do not interfere with other tasks (parallel) e.g. talking, stirring a pot, listening to radio, buttoning shirt

REM (rapid eye movement)

an active brain in a paralysed body

Altered State of Consciousness (ASC)

any state of consciousness that is distinctly different from normal waking consciousness in terms of level of awareness and experience . mental processing of internal and external stimuli shows measurable changes . e.g. self-awareness, emotional awareness and perceptions of time, place and one's surroundings may change. In addition, normal inhibitions or self-control may weaken

Drugs

any substance that can change a person's physical and/or mental functioning

Procedure for Dawson & Reid (1997)

both groups of participants were assessed on 'cognitive psychomotor performance' at half-hourly intervals . computer-administered test of eye-hand coordination involving an unpredictable tracking task . as well as visual-motor integration, the eye-hand task used in the experiment requires concentration (i.e. selective attention), speed, accuracy and decision making

Consciousness as a psychological construct

cannot be directly observed or measured, thus, it is referred to as a psychological (or hypothetical) construct

NREM stage 4 (deepest)

deepest stage of sleep with the highest arousal threshold . when the EEG shows that delta waves comprise more than 50% of the brain wave activity, the person has entered stage 4 PREDOMINATELY delta waves PHYSIOLOGICAL CHANGES include our muscles are completely relaxed, we barely move and there are no eye movements . heart rate, blood pressure and body temperature are at their lowest and most regular ACCOUNTS FOR about 10 to 15% of total sleep time

REM

defined by spontaneous bursts of rapid eye movement during which the eyeballs quickly move beneath the closed eyelids, darting back and forth and up and down in jerky, but coordinated movements PREDOMINATELY beta-like waves PHYSIOLOGICAL CHANGES include body's internal functioning is more active; thus, heart rate is faster and more irregular, blood pressure rises, and breathing is quicker and more irregula ACCOUNTS FOR approximately 20-25% of our total sleep time

DELTA waves

delta waves are most commonly associated with deep, dreamless sleep or anaesthesia/coma.In the deepest sleep, there is a predominantly delta brain wave pattern . low FREQUENCY (slow) and high (large) AMPLITUDE

Electromyograph (EMG)

detects, amplifies and records the electrical activity of MUSCLES \ . indicates changes in muscle activity (movement) and muscle tone (tension)

Induced ASCs

do not occur naturally and are instead induced (intentionally achieved by the use of some kind of aid) e.g. meditation, hypnosis, alcohol ingestion, medications or illegal drugs

Depressants

drugs that decrease activity in the central nervous system and the rest of the body . can induce ASC

Stimulants

drugs that increase activity in the central nervous system and the rest of the body . have an alerting, activating effect . can induce ASC

Measurements of physiological responses

enable researchers to obtain data on bodily changes and responses during various states of consciousness

Generalising for Dawson & Reid (1997)

generalising the findings to real-life settings from computer simulations often involving relatively simple tasks under controlled laboratory conditions requires careful consideration of a wider range of variables that also impact on human performance including the interactions between sleep deprivation and alcohol consumption combined . although there are exceptions, similar results have since been obtained by other researchers on a variety of cognitive and concentration tasks

Amplitude

intensity/how big the peaks and troughs are from a baseline of zero activity

REM as 'paradoxical sleep'

internally, the brain and body are active, while, externally, the body appears calm and inactive

Circadian rhythm

involve changes in bodily functions or activities with a duration of 24 hours

REM rebound

involves catching up on REM sleep immediately following a period of lost REM sleep by spending more time than usual in REM sleep when next asleep

Selective attention

involves choosing and attending to a specific stimulus to the exclusion of others . more likely to attend to stimuli that are important to us, that change or are novel . can still process some information outside conscious awareness e.g. internal (pain in your foot) or external (watching a car drive by)

Blood-alcohol concentration (BAC)

measure of alcohol in the body expressed as grams of alcohol/100 mL of blood

Electro-oculargraph (EOG)

measures eye movements/positions by detecting, amplifying and recording electrical activity in the EYE MUSCLES that control eye movements . has clarified distinction between rapid eye movement and non-rapid eye movement sleep

Accuracy

number of correct responses and incorrect responses (errors) made

Ultradian rhythms

occur multiple times within a 24-hour period

NREM stage 1 (lightest)

occurs as we drift into and out of a true sleep state . tend to gradually lose awareness of ourselves and our surroundings, but some of the time we may be aware of faint sounds in our environment PREDOMINATELY alpha waves PHYSIOLOGICAL CHANGES include a decrease in heart rate, respiration, body temperature and muscle tension ACCOUNTS FOR about 4 or 5% of the total sleep time

Sleep: key characteristics

on average we go through ONE CYCLE of NREM (not necessarily all 4 stages) and REM every 90 MINUTES . most adults experience 5-6 NREM/REM cycles per night . the amount of time spent in REM sleep increases and NREM sleep decreases as the night progresses

Consciouness

our awareness of objects and events in the external world, and of our sensations, mental experiences and own existence at any given moment

Measurement of speed and accuracy on cognitive tasks

participants complete one or more cognitive tasks across a number of trials and mean scores are calculated . both (speed and accuracy) considered objective measures because their scores are not subject to interpretation e.g. cognitive tasks can involve learning, memory, spatial processing, reasoning, decision making or problem solving

Research findings (24 hours)

performance following 24 hours of sustained wakefulness was equivalent to that of someone with a BAC of 0.10%

Research findings (17 hours)

performance on cognitive tasks following 17 hours of full sleep deprivation ('sustained wakefulness') decreases to a level equivalent to that of a person with a blood-alcohol concentration (BAC) of 0.05% (legal driving limit in Australia)

Sleep episode

period from sleep onset to awakening

Slow wave sleep

primarily because of their similarities in relation to physiological responses, stages 3 and 4 are now commonly combined and described as one stage . important for memory consolidation . DELTA waves

Effects of depressants

reduces . alertness . environmental awareness . responsiveness to sensory stimulation . cognitive functioning . physical activity SMALL DOSES = feeling more relaxed and less inhibited LARGE DOSES = loss of control (so 'distinctly different' characteristics of consciousness appear) LARGER DOSES = unconsciousness and death

Speed

response or reaction time to a stimulus

Restorative theory

sleep allows us to recharge our bodies, recover from physical and psychological work during the day, and allows our body's growth to occur

Frequency

speed/number of waves produced in a cycle of activity

Effects of stimulants

stimulants can affect our conscious experiences by changing the CHARACTERISTICS of consciousness (attention, mood, emotional awareness, self-control, time orientation, thinking, memory, judgement...) . we might feel more alert, focussed, confident, motivated, 'well' and be more happy and sociable . amphetamines stimulate or EXCITE the sympathetic NS, producing similar physiological changes as in FFF to a threat or stressor

Evolutionary theory

suggest sleep evolved to enhance survival by making organisms inactive when they are most vulnerable to attack . animals are less likely to attract predators when they are not awake and interacting with the environment

Divided attention

the ability to distribute our attention and undertake two or more activities simultaneously . Easier when the tasks are sufficiently similar, not complex, well known . often we may think we are using divided attention, but we are actually shifting attention from one task to another . generally reduces performance on both tasks e.g. washing a car while listening to the radio

Long-term effects of stimulants

the more potent the stimulant, the longer the changes are likely to go for and vice-versa . psychological impairments . psychosis (total lack of connection to reality) . hallucinations . paranoia . aggressive or violent behaviour . cognitive impairments.

NREM stage 3

the start of the deepest period of sleep . an interim or transitionary stage between the shallow sleep of stage 2 and the deep sleep of stage 4 PREDOMINATELY delta waves (20% - 50%) and theta waves PHYSIOLOGICAL CHANGES include heart rate, blood pressure and body temperature continue to drop, and the breathing rate continues to be slow and steady ACCOUNTS FOR about 3 to 8% of total sleep time

Normal Waking Consciousness (NWC)

the states of consciousness associated with being awake and aware of objects and events in the external world, and of one's sensations, mental experiences and own existence . organised clear thoughts . perceive the world as real, accurate perception of time and place

Video monitoring

video cameras use infrared technology so that recordings can be made in conditions of little or no light . subjective . records externally observable physiological responses

ALPHA waves

when we are awake and alert but mentally and physically relaxed and internally focused, the EEG shows a predominantly alpha brain wave pattern . medium to relatively high FREQUENCY (but slower than beta waves) with low AMPLITUDE (but a slightly larger amplitude than beta waves)

Sleep cycle vs Sleep stages

while the overall sleep-wake cycle is a circadian rhythm, the different stages within it are ultradian rhythms