Sleep Flashcards
why is sleep a psychological construct?
because it is an entity we believe to exist because we can measure its effects but not the entity itself
what is a psychological construct?
an agreed upon description and understanding of psychological phenomena which cannot be overtly measured or observed
what are the states of consciousness?
- normal waking consciousness
- altered states of consciousness
what is normal waking consciousness?
the state of consciousness that most people spend the majority of their time in
- Characterised by the ability to be aware of both internal and external stimuli
what is altered states of consciousness?
a broad term that covers any state of consciousness that differs from normal waking consciousness
what are the types of ASCs?
- induced altered state of consciousness
- naturally occurring states of consciousness
what is consciousness?
the awareness of internal and external stimuli
what are the characteristics of sleep?
- reduced ability to control behaviour
- less accurate understanding of the passage of time
- reduction in the control we have over thoughts
characteristics of REM sleep
- highly active brain & less active body
- virtually paralysed from the neck down
- relatively light stage and the sleeper can be woken fairly easily
- vivid dreaming that can be frequently recalled
- time spent in REM increases as the sleep episode goes on
characteristics of NREM sleep
- sleeper is considered to have a less active brain
- physical movement is possible as the body is more active
- movement decreases as NREM progresses
- dreams are non-vivid and not frequently recalled
- approx 75-80% of a sleep episode is spent in NREM
What are the key characteristics of NREM 1?
- sleeper transitions from being awake into a light sleep
- signified by the hypnagogic state where people experience a sudden jerk
- sleeper looses awareness of themselves and their surroundings
- still aware of faint sounds and can be easily woken
what are the key characteristics of NREM 2?
- sleeper is in a relatively light sleep
- in this stage the sleeper is considered truely asleep due to the type of brain waves occurring
what are the key characteristics of NREM 3?
- sleeper is considered in a deep sleep and difficult to wake
- sleepwalking and sleep talking most likely to occur
what is an electroencephalograph (EEG)?
a device that detects, amplifies and records the electrical activity of the brain
what are the key characteristic of an EEG?
- Electrical impulses are detected by the EEG and then presented as brain wave patterns
- Measure the electrical impulses made by the neurons
- In Normal waking consciousness the EEG will show higher frequency and a lower amplitude
- In an altered state of consciousness the EEG will show lower frequency and a higher amplitude
what is an advantage of EEGS?
useful for sleep studies or diagnoses of patients with brain damage or a neurological or mental disorder, such as tumours, sleep disorders and Alzheimer’s
what is a disadvantage of EEGS?
it measures neural activity underneath a thick skull and therefore is no entirely precise, and it cannot pinpoint or identify dysfunctional areas of the brain like an MRI
what is an electromyograph (EMG)?
a device that detects, amplifies and records the electrical activity of the bodys muscles by attaching electrodes to the skin
What are the key characteristics of an EMG?
-Muscle movement and tension used to identify the different stages of sleep
- REM sleep the EMG will show low activity due to low levels of physiological activity
- During NREM sleep the EMG will show medium/moderate activity as there is some physiological activity
- As NREM progresses an EMG will show lower levels of activity
what is an electro-oculograph (EOG)?
a device that detects, amplifies and records the electrical activity of the muscles around the eye responsible for eye movement
What are the key characteristics of an EOG?
-Movement of eye muscles is measured by electrodes that are attached to the skin above the muscles
- REM an EOG is likely to show high activity
- During NREM sleep an individual doesn’t experience rapid eye movement- EOG is likely to show low activity
what is a sleep diary?
a record containing self-reported descriptions from an individual about their sleeping periods
what type of data is a sleep diary?
subjective, qualitative & quantitative, primary
what is an advantage of sleep diaries?
they provide qualitative information with extensive detail and description
what is a limitation of sleep diaries?
as the patient is responsible for recording the information, it is subjective and therefore may not be accurate
what is video monitoring?
involves the use of camera and audio technologies to record an individual as they sleep
what are circadian rhythms?
biological and behavioural changes that occur as part of a cycle that lasts around 24 hours eg: sleep-wake cycle
what is the sleep wake cycle?
a type of circadian rhythm that is made up of a 24 hour period that an individual spends sleeping and being awake and alert
what are ultradian rhythms?
biological and behavioural changes that occur in a cycle that lasts less than 24 hours
how many sleep cycles to individuals have in an episode?
approximately 5-6
what is the superchiasmatic nuclear?
area of the hypothalamus that is responsible for regulating an individuals sleep-wake patterns, an internal body clock.
- The SCN receives information from both external and internal cues to help moderate the circadian rhythm
what are external cues?
involve information from the environment such as the presence or absence of light
what are internal cues?
involve information that originates from within the body (such as the presence or suppression of genes known as clock genes)
what is the SCN process?
1.The SCN receives external cues and internal cues
2.After receiving both external and internal cues the SCN sends neural messages (signals) to the pineal gland to produce and release melatonin
3.The pineal gland releases melatonin into the bloodstream, which promotes feelings of calm and relaxation, therefore promoting sleep
what is full sleep deprivation?
when an individual has no sleep in a 24-hour period-
what is partial sleep deprivation?
when an individual sleeps for some duration within a 24-hour period, but the sleep is too short, or the quality of sleep is poor.
what is an affective effect of sleep deprivation?
- Poor emotional regulation resulting in amplified emotional responses
- A reduced ability to cope with stress internally
what is a behavioural effect of sleep deprivation?
- Excessive sleepiness during the day and taking micro sleeps throughout the day
what is a cognitive effect of sleep deprivation?
- Lapses in attention and a short attention span
- Impaired decision-making processes and problem-solving abilities
what is the BAC for partial sleep deprivation?
0.05
what is the BAC for full sleep deprivation?
0.10
what are circadian rhythm sleep disorders?
sleep disorders that interfere with the typical regulation of the circadian rhythm of sleep, leading to a change in the sleep wake cycle
what is delayed sleep phase syndrome?
a type of circadian rhythm sleep disorder in which sleeping and waking occur later than usual
what is advanced sleep phase disorder?
a type of circadian rhythm disorder in which sleep and waking occur earlier than usual
what is shift work?
working at unusual hours, such as working overnight which means having to sleep at unusual times
What is bright light therapy?
a method used to adjust a persons circadian rhythm through exposure to a high-intensity light source
what is the process of bright light therapy?
- an individual is exposed to the light source
- SCN receives this as an external cue which acts as a biological mechanism to regulate the sleep-wake cycle
- readjusts the circadian rhythm and ensures that sleeping and waking occur at the desired time
what are zeitgebers?
external cues from the environment that influence the circadian rhythm
what is a sleep episode
A sleep episode is the full duration of time spent asleep. Made up of multiple 90-minute (approx.) repeated cycles of REM and NREM sleep called sleep cycles
how can time contribute to sleep hygiene?
sleeping and waking at a time that enables an adequate amount of sleep, and doing so at a consistent time each day (social factors may pose a risk)
what is sleep hygiene?
a term used to describe the practices and habits that promote an individual’s sleep patterns, improving the quality and quantity of sleep
how can light contribute to sleep hygiene?
sleeping in a dark space and reducing bright light exposure close to sleeping time
how can association with bed contribute to sleep hygiene?
avoiding doing activities other than sleeping in bed (like watching tv and studying)
how can light act as a zeitgeber?
Therefore, exposure to daylight/blue light at nighttime can reduce sleepiness
how can temperature act as a zeitgeber?
Link between having a cool room temperature and experiencing improved quality and quantity of sleep. Believed because body temperature drops during sleep and therefore a cool room helps to cool body temperature
how can eating and drinking act as a zeitgeber?
Types of food and drink that individuals consume can impact the quality and quantity of sleep (timing and amount)
what foods/drinks act as a zeitgeber for sleep?
caffeine, alcohol, high sugar/high fat foods, spicy foods
