5.1—biological rhythms of consciousness: wakefulness and sleep Flashcards
1
Q
Consciousness
A
a person’s subjective awareness, including thoughts, perceptions experiences of the world, and self-awareness.
2
Q
Biological Rhythms
A
- Different types of Biological Rhythms:
- circannual rhythm: a cycle that happens yearly (e.g. hibernation)
- infradian rhythm: rhythm that occurs longer than a day (e.g. menstrual cycle)
- ultradian rhythms: extremely frequent cycles (e.g. urination, hearth rate, breathing)
- circadian rhythms: (are the most important) internally driven daily cycles of approximately 24 hours affecting physiological and behavioural processes (e.g. hunger and sleep)
3
Q
Suprachiasmatic Nucleus (SCN)
A
- a key brain structure of the hypothalamus.
- relays light levels in the environment to the pineal gland which in turn, releases melatonin.
- explains why we are more awake during the daytime and sleepy during nighttime.
4
Q
Stages of Sleep
A
- awake
- stages 1-4
- REM sleep
5
Q
Polysomnography and Electronecephalogram (EEG)
A
- polysomnography: a set of objective measurements used to examine physiological variables.
- electronecephalogram: a device that measures brain waves.
6
Q
Stages 1-4 or Non-REM (NREM)
A
brain waves decreases in frequency and increases in amplitude as sleep progresses through the four stages.
7
Q
REM Sleep
A
- REM sleep: a stage of sleep characterized by quickening brain waves, inhibited body movement, and rapid eye movements.
- brain waves increases in frequency and decreases in amplitude (the same level as when we are awake), despite being asleep.
- affects our ability to learn and is extremely important.
- lack of REM sleep can impair ability to learn.
8
Q
Sleep Cycle
A
- go through the 4 stages of sleep into REM, then go through 4 stages again.
- happens multiple times throughout the night.
- the duration of REM increases with each cycle.
9
Q
Restore and Repair | Theory of Sleep
A
the idea that the body needs to restore energy levels and repair any wave and tear experienced during the day’s activity.
10
Q
Preserve and Protect Hypothesis | Theories of Sleep
A
suggests that two more adaptive functions of sleep are preserving energy and protecting the organism from harm.
11
Q
Sleep Deprivation
A
- occurs when an individual cannot or does not sleep.
- can cause multiple impairments including difficulties with multitasking, maintaining attention for long periods of time and assessing risk.
12
Q
Sleep Displacement
A
- occurs when an individual is prevented from sleeping at the normal time although she may be able to sleep earlier or later in the day than usual.
- e.g. jet lag and daylight savings
13
Q
Freud’s Theory of Dreaming
A
- dreams represented our desires.
- two forms of imagery in dreams:
- manifest content: involves the images and storylines that we dream about.
- latent content: the actual symbolic meaning of a dream built on suppressed sexual or aggressive urges.
14
Q
Activation-Synthesis Hypothesis
A
- suggests that dreams arise from brain activity originating from bursts of excitation messages from the pons (a part of the brain stem).
- imagine having a dozen different people each provide you with one randomly selected word, with your task being to organize these words to look like a single message; this is essentially what your cortex is doing every time you dream.
15
Q
Insomnia
A
- a disorder characterized by an extreme lack of sleep.
- different types of insomnia:
- onset insomnia: when a person has difficulty falling asleep (30 minutes or more).
- maintenance insomnia: when an individual cannot easily return to sleep after waking in the night.
- terminal insomnia or early morning insomnia: a situation in which a person wakes up too early (sometimes hours too early) and cannot return to sleep.
- for a sleep disorder to be labelled insomnia, the cause of lack of sleep must be internal (i.e. trying to sleep in a loud environment does not count).
- secondary insomnia: insomnia caused by depression, pain, too much caffeine etc.
- insomnia disorder: insomnia in which insomnia is the only symptom and all other causes are ruled out.
16
Q
Nightmares and Night Terrors
A
- nightmares: particularly vivid and disturbing dreams that occur during REM sleep.
-
night terrors: intense bouts of panic and arousal that awaken the individual, typically in a heightened emotional state.
- a person experiencing a night terror may call out or scream, fight back against imaginary attackers, or leap from the bed and start to flee before waking up.
17
Q
Restless Legs Syndrome and Somnambulism | Movement Disturbances
A
-
restless legs syndrome: a persistent feeling of discomfort in the legs and the urge to continuously shift them into different positions.
- is linked to the dopamine system and to an iron deficiency.
-
somnambulism: (or sleepwalking) a disorder that involves wandering and performing other activities while asleep.
- there are no medicine that treats sleepwalking.
18
Q
Sexomnia and REM Behaviour Disorder | Movement Disturbances
A
-
sexomnia: a disorder in which individuals engage in sexual activity such as the touching of the self or others while in stages 3 and 4 sleep.
- the cause is unknown although stress, fatigue, and a history of trauma are all possible factors
-
REM behaviour disorder: a condition in which individuals act out the content of their dreams (unlike sleepwalking).
- can be treated with medication such as benzodiazepines.
19
Q
Sleep Apnea
A
- sleep apnea: a disorder characterized by the temporary inability to breathe during sleep.
- prevalent amongst overweight and obese individuals.
- is usually caused by blockage to the airway but can also be caused by the brain’s failure to regulate breathing (this is more rare).
20
Q
Narcolepsy
A
- narcolepsy: a disorder in which a person experiences daytime sleepiness and even sleep attacks.
- medications are available to treat narcolepsy.
21
Q
Overcoming Sleep Problems
A
- practicing good sleep hygiene (healthy sleep-related habits) are the most beneficial.
- medication can also help but should be used as a last ditch effort.
