SAC #6 U4 AOS 1 Test

consciousness

the level of awareness of our thoughts, feelings and perceptions and our own existence at any given moment

why is consciousness referred to as a psychological construct

It is believed to exist, but needs to be constructed to describe it. It cannot be measured directly however can be inferred from self-reports, observed behaviour and physiological measures.

what is the purpose of the continuum of consciousness

consciousness is continuous and changing and the continuum highlights the varying levels of awareness of our internal and external environment. The higher the activity is on the continuum, the higher the level of consciousness

ranking of ASC's on the continuum of consciousness. (high to low)

daydreaming, meditative state, hypnotised, asleep, anaesthetised, coma.

normal waking consciousness (NWC)

a state that is organised, clear and meaningful, and the individual is awake and aware of their thoughts, feelings and perceptions and they have heightened awareness of internal and external environments

altered state of consciousness (ASC)

a state which is distinctly different from normal waking consciousness in terms of level of awareness of thoughts, emotions, and perception and the internal and external environment.

naturally occurring ASCs

sleep and daydreaming

Purposely induced ASCs

meditation, hypnosis, alcohol induced state, drug induced state, anaesthetised and in a coma

attention

it is a concentration of mental activity that involves focusing on specific stimuli, whilst ignoring other stimuli. it can shift consciously or unconsciously to internal or external stimuli

selective attention

it involves choosing and attending to a specific stimuli to the exclusion of others that we choose to ignore.

cocktail party phenomenon

it is the ability to concentrate on one voice amongst a crowd by focusing your attention on selected aspects of the environment and blocking out the rest. (you could be at a party and despite being totally involved in one conversation, you can switch your attention to another conversation after hearing your name.)

divided attention

it involves the ability to distribute attention and undertake two or more activities simultaneously. (e.g. using a stationary bike at the gym which is an automatic procedural memory and at the same time, watching TV which also generally requires little conscious effort)

controlled process

A task that requires conscious alert awareness, a high level of mental effort, and thus selective attention to complete. (e.g. performing brain surgery)

automatic process

a task that can be completed with a relatively lower level of mental effort and thus the individual can divide their attention between multiple tasks and it does not interfere with the performance of other tasks. (e.g. riding an exercise bike at the gym)

electroencephalograph (EEG)

it detects, amplifies and records electrical activity of the brain via a series of electrodes attached to the scalp

electro-oculograph (EOG)

it detects, amplifies and records electrical activity of the eye muscles that control eye movement

electromyograph (EMG)

it detects, amplifies and records electrical activity of the muscles which is indicative of muscle tension or muscle twitching

physiological measures during REM sleep

on an EEG there is higher frequency, lower amplitude beta like waves. on an EOG there is higher electrical activity due to rapid eye movement. on an EMG there is lower electrical activity due to REM paralysis

physiological measures during NREM sleep

on an EEG, there is lower frequency, higher amplitude alpha, theta and delta brain waves. on an EOG there is lower electrical activity due to non rapid eye movement. on an EMG there is higher electrical activity indicating greater muscle tension.

physiological measures during an alert state

on an EEG there is higher frequency, lower amplitude beta brain waves. on an EOG there is higher electrical activity due to activities such as scanning traffic when driving. on an EMG there is moderate to high electrical activity.

advantages of using physiological responses to indicate consciousness

they provide reliable, objective, unbiased, quantitative data that can be used to indicate an individual's state of consciousness.

disadvantages of using physiological responses to indicate consciousness

they do not provide qualitative information about thoughts and feelings or explain why. the observed differences in electrical activity could be due to factors other than a change in consciousness, thus they may lack validity.

beta waves

they are fast and have high frequency but they are small peaks and troughs and thus have low amplitude. they are typically associated with normal waking consciousness, when we are alert, attentive to external stimuli and we are doing intensive mental activity.

alpha waves

they have high frequency but are slower than beta waves, and have low amplitude but the peaks and troughs are higher than beta waves. they are typically associated with a relaxed, calm, internally focused, wakeful state, with our eyes closed, such as daydreaming or early stages of sleep.

theta waves

they have a medium frequency which is slower than beta and alpha waves and they have a mixture of high and low amplitude waves. they are typically associated with drowsiness, falling asleep, awakening from sleep, creative activities, in a meditative state, and when we are drunk

delta waves

they are the slowest and have the lowest frequency. however they have the biggest peaks and troughs and thus the highest amplitude. they are typically associated with the deepest stage of sleep, that is stage 3 and 4 of NREM, as well as a highly meditative state.

self-reporting to investigate consciousness

the data is provided by the individual via a sleep diary, survey or questionnaire and it can include qualitative data such as a description of the quality of sleep or quantitative data such as number of night-time awakenings

advantages of self-reporting to investigate consciousness

they can provide rich qualitative data about thoughts, feelings and behaviours and they may help researchers to find things such as causes of insomnia.

disadvantages of self-reporting to investigate consciousness

the accuracy and reliability can be limited due to the subjectivity of the recording process.

video monitoring to investigate consciousness

It uses infrared cameras to monitor sleep patterns to investigate observable sleep phenomena such as sleepwalking.

advantages of video monitoring to investigate consciousness

it doesn't disrupt the sleeper because no wires need to be connected to the individual and it produces quantitative data that provides insight into observable behaviours during sleep.

disadvantages of video monitoring to investigate consciousness

it doesn't provide any qualitative information on thought processes and it is open to experimenter bias of interpretation of observed behaviour.

measurement of speed and accuracy of cognitive tasks

information is gathered by testing a task for speed and the time taken to complete a task and then measuring for accuracy and the number of accurate and inaccurate responses

advantages of measuring speed and accuracy of cognitive tasks

it provides objective data that is more reliable than self-reporting and it provides useful information on the effects of different physiological states on levels of alertness

disadvantages of measuring speed and accuracy of cognitive tasks

it only provides quantitative data, it does not indicate thought processes or feelings

level of awareness during an ASC

level of awareness of internal state and external environment is generally diminished

level of awareness during a NWC

the level of awareness is relatively heightened as we are awake and typically aware of our internal state and the external environment and we have a relatively sound sense of self, reality and time

content limitations during a NWC

the information and other stimuli that we are aware of is more limited, and our thoughts tend to be more logical and organised and certain stimuli is repressed

content limitations during an ASC

the information and other stimuli that we are aware of is less restricted and less limited and so we are prone to more bizarre and unrealistic or creative thoughts

controlled processes during a NWC

we can competently complete a task that requires a high level of conscious awareness and at times we can complete an automatic process simultaneously

controlled processes during an ASC

it can impair our ability to complete a controlled process more than an automatic process

automatic processes during a NWC

we can competently complete a task that requires minimal conscious awareness and mental effort and we can complete multiple automatic processes at once

automatic processes during an ASC

it can impair our ability to complete a task that requires minimal conscious awareness and mental effort

perceptual distortions during a NWC

we can make clear and rational sense of sensory input

perceptual distortions during an ASC

ASCs such as daydreams or alcohol induced states can reduce our perceptions or dull individuals to an extent that some sensations are not experienced at all. however some stimulant drugs can enhance our perception and make us more receptive to external stimuli

cognitive distortions during a NWC

our thoughts are rational, clear and organised and we can store new memories and readily access memories from LTM when required

cognitive distortions during an ASC

it can cause distorted, illogical thoughts and can impair decision making and problem solving. it can also affect our ability to store new memories or retrieve existing memories

emotional awareness during a NWC

we can monitor our emotions and we generally exhibit predictable emotional reactions to events.

emotional awareness during an ASC

we are more likely to have reduced emotional awareness and less control over our emotions. we may feel emotionless or produce unpredictable emotional responses

self-control during a NWC

we can monitor and control our behaviour as well as maintaining coordination of movements

self-control during an ASC

generally self-control is reduced and we have a reduction in our coordination and inhibitions. however hypnosis may help us to gain greater self-control over addictions

time orientation during a NWC

time is perceived relatively accurately and we can shift our attention from past to present to future

time orientation during an ASC

our time orientation is reduced and we perceive time less accurately

stimulants

they increase central nervous system activity and thus they increase the level of alertness. (e.g. caffeine, cocaine).

effects of stimulants on brain wave activity

they increase the frequency and decrease amplitude of brain waves, resulting in increased beta waves and a decrease in alpha, theta and delta waves in comparison to a normal waking consciousness.

depressants

they decrease central nervous system activity and thus they reduce the level of alertness. (e.g. alcohol, opiates, marijuana)

effects of depressants on brain wave activity

they decrease frequency and increase amplitude of brain waves, resulting in a decrease in beta wave activity and an increase in alpha, theta or delta waves compared to a normal waking consciousness

compare one night of full sleep deprivation vs a legal BAC in terms of cognition

a full night of sleep deprivation will have a more significant impact on cognition than a legal BAC, as a lack of sleep will result in more illogical thought processes and difficulty with decision making in comparison to a legal BAC of 0.049 or less

compare one night of full sleep deprivation vs a legal BAC in terms of concentration

sleep deprivation will diminish the attention span, making it more difficult to concentrate and use selective attention compared to a legal BAC

compare one night of full sleep deprivation vs a legal BAC in terms of mood

sleep deprivation negatively impacts mood and generally makes the individual more moody and irritable. Alcohol can enhance mood and generally increases our confidence but it can sometimes negatively impact mood.

compare one night of full sleep deprivation vs a legal BAC in terms of recovery

recovery from a full night of sleep deprivation may take a couple of nights of full sleep to recover the sleep debt. recovery from a legal BAC will only take a few hours for the alcohol to be removed from bodily systems

sleep deprivation vs blood alcohol concentrations

there will be similar effects on cognition and concentration for an individual who has not slept for 24 hours and someone with an illegal BAC of 0.1. The effects would also be similar for a driver with a BAC of 0.05 and a person who has been awake for 17 hours.

sleep

it is a naturally occurring altered state of consciousness which is characterised by a loss of awareness of our internal state and external surroundings

circadian rhythm

it is a biological rhythm spanning 24 hours and it regulates physiological and behavioural processes. (e.g. the sleep-wake cycle)

ultradian rhythm

it is a recurrent biological cycle that is repeated during a 24 hour period. (e.g. NREM-REM sleep cycles)

Exogenous zeitgebers

they are cues that are external to the body that regulate our sleep-wake cycle (e.g. light-dark)

endogenous pacers

they are internal cues that regulate our sleep-wake cycle (e.g. melatonin levels)

role of SCN

It is an area of the hypothalamus that receives information about the amount of light present in the environment from the eyes. Based on this information, it will adjust the sleep wake cycle accordingly by sending neural messages to the pineal gland to release melatonin.

role of melatonin

It is a sleep inducing hormone that is released into the bloodstream from the pineal gland when it is dark to make us drowsy. It will remain high during the night and then be reduced during the day when it is light.

role of cortisol

it is a source of energy that is released by the adrenal gland when it is light and our body temperature will increase which will make us more alert

distinguish between REM and NREM

REM has 1 stage, NREM has 4 stages. For an adult 20-25% of sleep is REM and 75-80% is NREM. In REM we have high frequency waves and in NREM there is relatively lower frequency brain waves. you cannot move in REM due to cataplexy but you are able to move in NREM. nightmares occur in REM whereas night terrors occur in NREM.

REM sleep

Rapid eye movement sleep constitutes about 20-25% of a typical night's sleep and it is a period where most dreaming occurs. it is called paradoxical sleep because internally the brain is active and externally the body appears calm and inactive due to muscle atonia

NREM stage 1 sleep

it is where sleep onset typically starts and it's the lightest stage of sleep, where we have low arousal threshold and a hypnic jerk may be experienced. in general brain waves are alpha waves as well as some theta waves.

NREM stage 2

it is still a light sleep and the body is more relaxed than stage 1. we spend more time in it than any other state. brain waves are predominately theta waves with some alpha waves

NREM stage 3

it is the start of deep sleep and so it is hard to wake the sleeper. it's known as slow wave sleep as on a EEG delta waves start to appear and more than 50% of the brain waves are theta waves

NREM stage 4

it is the deepest stage of sleep, and if woken we experience sleep inertia. more than 50% of this stage is characterised by delta brain waves on an EEG.

hypnagogic state

it is the transition from being awake to being asleep that generally lasts for 1-2 minutes and it is characterised by slow eye rolling movements and occasionally a floating feeling and a sudden jerk and images flashing briefly in our mind.

hypnic jerk

it is a brief involuntary muscle twitch or spasm of the body that occurs as we fall asleep during stage 1 of REM.

slow wave sleep

it is a period of sleep characterised by slower frequency delta brain waves that occur predominantly during NREM stage 3 and 4 and it indicates a low level of brain activity.

sleep inertia

it is a sleep to wake transition effect that occurs after being awakened from a deep sleep and it is characterised by grogginess, low alertness and disorientation, that can interfere with behavioural and cognitive functioning. if an individual is woken during stage 4 NREM, it will take up to 10 minutes for the individual to orient themselves.

sleep cycles (adults and adolescents)

we typically have 4-6 sleep cycles per night which last for 90-100 minutes

sleep cycles in terms of REM and NREM

from adolescence onwards we tend to only have deep sleep during the first two sleep cycles early in the night. the duration of each REM period increases with each cycle, and they occur closer together.

restoration theory of sleep

it is a theory on the purpose and function of sleep, proposing that sleep provides time out to help the body recover from activities that may have used up the body's physical and mental resources during the day

what is the purpose of NREM sleep according to the restorative theory

it is important in restoring physiological processes and energy stores within the body. it restores hormone levels and the immune system, as well as repairing damaged cells and tissue and enabling growth and development.

What is the purpose of REM sleep according to the restorative theory

it assists with learning and memory, through aiding the consolidation of new memories and it helps our wellbeing and mental health through dreams that enable us to deal with conflict and issues in our lives.

what are some of the potential symptoms of NREM sleep deprivation according to the restorative theory

an individual can become vulnerable to illness as the body becomes less resilient against infectious organisms and other invaders. it can also result in aches and pains as the body doesn't recover from wear and tear.

what are some of the potential symptoms of REM sleep deprivation according to the restorative theory

a lack of REM sleep can lead to moodiness and irritability as noradrenaline levels remain high. it can also impair memory processes, particularly the consolidation of learned material into long term memory.

evidence for the restoration theory of sleep

it is supported by the experiences most people have of feeling tired before they sleep and feel refreshed and more energetic upon waking. furthermore people usually sleep for longer periods of time during an illness, suggesting sleep may have something to do with the recovery process. REM sleep is also significantly higher for newborns, showing the role sleep plays in rapid brain development.

limitations of the restoration theory

quadriplegics still spend similar proportions of sleep in NREM, despite their lack of movements, indicating sleep may have other functions other than repairing wear and tear from physical activities. in addition, more active people do not necessarily sleep more and the amount of sleep doesn't necessarily decrease when our level of daytime activity decreases.

evolutionary theory

a theory on the purpose and function of sleep, proposing that sleep evolved to enhance survival by protecting an organism through making it active in order to fulfil vital functions and then inactive at the time of day when it is more risky and dangerous to move about.

according to the evolutionary theory why have humans evolved to sleep at night

humans have evolved to sleep at night because in the past, the absence of light caused visual limitations, thus increasing our risk of harm, and so it was safer to be asleep during the night.

evidence for the evolutionary theory

animals that have less predators such as lions, sleep considerably more than animals that have multiple predators and difficulty hiding, such as giraffes. smaller animals that eat less food and are able to hide themselves from predators more easily, spend less time searching for food and more time sleeping

Limitations of the evolutionary theory

it doesn't explain the need for sleep, just the timing of sleep. furthermore our loss of awareness at night can be maladaptive for our survival, as it makes us highly vulnerable to predators when we are physiologically the least prepared to respond due to our relaxed muscles.

why do infants have more REM sleep

REM sleep is important for brain development, so for newborn babies about 50% of sleep is REM sleep due to the rapid developmental plasticity of the brain that occurs during this early part of life.

why do elderly people have less deep sleep

they experience less growth and development and there may be a decline in melatonin levels so fragmented sleep prevents them from reaching deep sleep. slow wave sleep continues to decline by around 2% every decade.

sleep-wake shift for adolescents

they experience a delayed sleep onset by 1-2 hours, and melatonin is released later so they tend to stay up later than adults and tend to sleep in later than adults.

normal proportions of REM/NREM for adolescents and adults

they have roughly 20% of time in REM and 80% of time in NREM

sleep requirements for newborns

they sleep 15-18 hours per day, half of this is REM sleep due to the rapid brain development during infancy. their sleep patterns are generally irregular and they only experience circadian rhythms at around 2-3 months

sleep requirements for young children

they sleep an average of 11-13 hours per day and roughly half of their NREM sleep is comprised of deep sleep, however this ratio diminishes as they get older and older children tend to skip the first REM episode.

Sleep requirements for adolescents

They require 8.5-9.5 hours of sleep per night, 20% of this is REM sleep. they often experience delayed sleep onset by 1-2 hours and tend to have erratic sleep patterns due to school and their lifestyle