Variations in Consciousness & Sleep Flashcards
consciousness, sleep, sleep disorders, dreams
Consciousness
Consciousness is the awareness of internal and external stimuli.
*it is stream-like in nature (William James; “stream of consciousness”)
Perceptual richness
-Consciousness has been measured in animals in terms of perceptual richness
*perceptual richness: extent to which an animal is able to experience a sensory modality (sight, smell, hearing, vision)
Variations in consciousness (different combinations)
-attention ≠ consciousness
-it is possible to be conscious but not paying attention
example:
driving (↑consciousness + ↑attention)
vs.
sleeping (↓consciousness + ↓attention)
Mind wandering (definition)
def: when thinking veers off-task/thoughts that are not related to what you are intentionally trying to do at a given moment.
Mind wandering (pros and cons)
pros: future planning, boredom relief, creativity, etc,.
cons: costly to self (and others)
-in class; could miss important information
-while driving; could put others in danger
When is mind wandering most likely to occur?
the beginning and end of the week (mondays & fridays)
*it is estimated that people spend 15 to 50 percent of their time mind wandering
Sleep: circadian rhythms
def: 24-hr biological cycles that affect mind & body functions (particularly influential in sleep regulation but also blood pressure, urine production, hormonal secretions, etc.)
-the time of day that you eat + exercise will affect biological rhythms (earlier in the day is ideal for being in synch w/ your body clock)
How does the biological clock work?
light hits the retina→activates the suprachiasmatic nucleus (SCN) in the hypothalamus→sends message to pineal gland→release melatonin (sleep hormone)
Measuring circadian rhythms
-circadian rhythms can be computed via wearable technology, measuring body temperature, etc,.
Chronotypes (morningness & eveningness)
-morningness-eveningness: individual differences in preference for a given time of day (not everyone has the same optimal sleep time)
-morning[lark]
-evening[owl]
-intermediate
Chronotypes: biological markers
-body temp
-cortisol
-melatonin
-morning[lark] (melatonin release, cortisol release, and body temp rises earlier in the day)
-evening[owl] (melatonin release, cortisol release, and body temp rises later in the day)
-intermediate (more productive mid day)
Social jet lag
def: refers to the mismatch between an individual’s biological clock (circadian rhythm) and the demands of their social schedule, such as work or school.
-seen in evening owl
-not in sync
-harmful to the body & mind
Chronotype variation across 4 factors:
- Personality: Big Five variation (e.g., C&E), creativity (owl), persistence (lark).
*C&E=conscientiousness (lark) and extraversion (owl) - Age: eveningness shift seen at 12-13 yrs old (hanging out w/ friends), morningness shift seen in late adolescence (responsibilities earlier in the day such as work).
- Genetic: gene variant differences
-A-A (lark)
-A-G (intermediate)
-GG (owl) - Neural: white matter integrity
-can become compromised when you’re sleeping later in the day (due to social jet lag)
Researching sleep: 3 methods/devices (in lab settings)
*the brain does NOT shut off during sleep; there’s still brain activity
- EEG: electroencephalograph - waves (measures brain wave activity via electrodes attached to scalp)
- EMG: electromyograph - muscle (records muscle tension & activity)
- EOG: electrooculograph - eyes (records eye movements)
Factors that affect sleep variations
-income (↑income, ↓sleep)
-married (↓sleep)
-have children (↓sleep)
-age (older adults; require less sleep)
-gender (insomnia more common in women)
What is DEC2 gene mutation?
the DEC2 gene mutation aids those who sleep minimally; people with the gene can be most productive on 4-6 hrs of sleep.
Potential effects of sleep deprivation
-increased risk of accidents
-hypertension (↑BP)
-diabetes
-neg affect on immune system
Sleep cycle stages (5)
1) NREM (N1)
2) NREM (N2)
3 & 4) NREM (N3 & 4)
5) REM
*NREM=non-REM
NOTE: people usually repeat the sleep cycle about four times throughout the night, REM periods get progressively longer.
Sleep cycle stage 1: NREM (N1)
brain wave activity: alpha waves (higher frequency) transitions in to theta waves (lower frequency)
duration: 1-7 minutes (shortest stage)
changes: hypnic jerks. body temp, respiration rate, heart rate, and muscle tension start to drop.
Sleep cycle stage 2: NREM (N2)
brain wave activity: mixed waves, sleep spindles (high spike waves; visible on EEG)
duration: 30-60 minutes
changes: physio continues to drop
Sleep cycle stage 3 & 4: NREM (N3 & 4)
brain wave activity: delta waves (slower pattern; more spread apart) *SWS (slow wave sleep)
duration: approx 30 min each
changes: more physio drop
Sleep cycle stage 5: REM
*REM=rapid eye movements (side-to-side/lateral)
brain wave activity: beta waves (high frequency; similar pattern as if you were awake)
duration: varies greatly
changes: deep sleep, extreme muscle relaxation (virtually paralyzed), irregular breathing & pulse rate, vivid dreams.
Sleep factors: age (babies vs. old age)
“sleep like a baby”
-less stages (only 2; REM & NREM)
-more hours slept (16 hrs/day)
-babies spend more of their time in REM than adults
sleep in old age:
-lighter (N1 & N2)
-less sleep needed (better tolerance of sleep deprivation)
-wake up more frequently throughout the night
-sleep complaints; linked to health issues such as Alzheimer’s
Sleep factors: culture & sleep habits
monophasic:
-sleep 8 hours at one time
-western cultures
biphasic:
-sleep at night & mid-day rest
-“siesta cultures” (tropical regions)
polyphasic:
-multiple blocks of sleep at different times of the day due to rapid changing conditions
-hunter-gatherers
What are the 7 sleep disorders? (that we learned about)
- insomnia
- narcolepsy
- sleep apnea
- night terrors
- somnambulism
- REM sleep behaviour disorder
- nightmares
Insomnia
*most common sleep disorder
def: persistent trouble w/ falling asleep or remaining asleep (also can be persistent early morning awakening).
-more common in women
-worsens with age
-1 in 10 people are affected
-linked to diabetes, hypertension, heart disease, and GI problems
-increased absenteeism
Narcolepsy
def: falling into short REM sleep bouts involuntarily.
-happens due to orexin loss (neuropeptide) in the hypothalamus
-genetic influence
-extremely dangerous (e.g., while driving)
-treatment: stimulants (not 100% effective)
*relatively uncommon
Sleep apnea
def: reflexive gasping for air, awakens sleeper & disrupts sleep.
-treatments: drugs, weight loss, surgery, special equipment (CPAP machine)
*CPAP=continuous positive airway pressure machine
Night terrors
def: abrupt awakenings from NREM sleep, with intense autonomic arousal and panic.
-more common in children (generally outgrow)
-associated with stress
-often temporary
NOTE: occurs in NREM, whereas nightmares occur in REM
Somnambulism
def: sleep walking (occurs in NREM)
-more common in children
-genetic influence
-can be triggered by drug use, prior sleep deprivation, and stress
REM sleep behaviour disorder
def: acting out REM dreams (talk, yell, gesture, flail about, or leap out of bed).
-commonly dream about being chased (violent)
-more common in men
-usually occurs in late adulthood (50s-60s)
-occurs due to brainstem deterioration
NOTE: the brainstem is responsible for (paralysis-like) muscle relaxation during REM, body movement should not occur.
Nightmares
def: anxiety-filled REM dreams that wake people
-more common in children
-stress-related (is the most common symptom of PTSD)
-occurs in REM
REALITY CHECK: effects of sleep deprivation
misconception: effects of partial sleep deprivation are generally insignificant.
reality: sleep deprivation impairs attention, motor skills, decision making, and memory. & increases risk of many kinds of accidents.
*sleep loss=increased vulnerability to a variety of diseases and elevated mortality.
Common treatments for insomnia
one of 2 sedatives: benzodiazapenes or nonbenzodiazapenes
issues:
-OD
-carryover effects (drowsy next day)
-dependency
-withdrawal
Alternatives to sedatives
-melatonin
-magnesium
-CBT (cognitive behavioural therapy)
-avoid blue-light before bed (tv & electronics)
-no afternoon caffeine
-black-out curtains
REALITY CHECK: dangerous to wake sleep walkers?
misconception: sleepwalkers are acting out their dreams and it is dangerous to wake them.
reality: sleepwalking does not occur in conjunction with dreams & waking them is much safer than letting them wander about.
Dreams (definition) & nature of our dreams
def: mental experiences with various characteristics (events, characters, etc,.)
-dreams are generally very mundane; common themes, often self-centered (through your own eyes, about your own life)
Dream content & cultural variation
most common:
-chased or pursued
-sexual experiences
-falling
-school, teachers, studying
cultural variation:
example: Siriano people have food shortage; common to dream about hunting or food acquisition
What are the 3 key dream theories? (and who is the associated theorist?)
- Wish Fulfillment (Freud)
- Problem-Solving (Cartwright)
- Activation-Synthesis Model (Hobson)
Dream theories: Wish Fulfillment
-theorist: Freud
-dreams fulfill residual goals of the day
2 key terms:
-manifest=what you’re dreaming about
-latent=meaning/interpretation of a dream
Dream theories: Problem-Solving
-theorist: Cartwright
-dreams may aid in over-coming barriers in problem-solving (e.g., more creative thoughts)
-critique: a dream might just be about a problem, not always a solution
Dream theories: Activation-Synthesis Model
-theorist: Hobson
-dreams are side effects during REM sleep; a by-product of periodic neural activation
critiques:
-meaningfulness (not all dreams are random, some are meaningful/relevant)
-occasional dreaming occurs in NREM
REALITYCHECK: fatal dreams
misconception: if you fall from a height in a dream, you’d better wake up on the plunge downward, because if you hit the bottom, the shock to your system could kill you in your sleep.
reality: no one has ever testified to experiencing a fatal dream. this myth presumably exists because many people do awaken during the downward plunge, thinking that they’ve averted a close call.
*people do have dreams about their own death—and live to tell about them.
Can short naps be refreshing?
it depends on:
-nap length (no longer than 30-45 min)
-type of sleep (stages 3-4=beneficial)
-time of day (not too late in the afternoon)
positive effects:
-improved attention + memory
-creativity
What’s the significance of snoring?
can be caused by:
-allergies
-certain drugs
-weight (or weight gain)
treatments:
-weight loss
-CPAP machine
Why don’t some people remember their dreams?
-wake time matters (people tend to remember the last dream they had before waking)
-people only recall specific types of dreams
