Transcript What is Psychology? - Warren Wilson College

Sleep
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Sleeping and waking
rhythms
• Biological rhythms in animals:
– Annual cycles
– Monthly cycles
– 24-hour cycles (circadian)
• Levels of consciousness vary
throughout a 24-hour period
– Ninety-minute cycles (stages of
sleep)
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Sleep Facts
Sleep is an interplay
between:
•Internal biological
clock (circadian
rhythms), and
•External factors
(e.g., light/dark
cycles, sociocultural
factors, stressors)
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Physiological assessment
of sleep
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Stages of Sleep
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Sleep architecture
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Dreams
• Function of Dreams?
– Freud
– “Daytime residue”
– Activation-Synthesis Hypothesis
• “What’s in a dream?” (video Sci Amer #14))
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Sleepless in Swannanoa
(Sleep Deprivation and its Effects)
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How much do we need and why
do we need it?
Reference: NSF
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Sleep as restorative
Sleeping brain is active: Regulates immune
and endocrine functions essential for
general health
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Sleep as a necessity
Main Point:
Sleep has a strong impact on our
waking life: from mood to
alertness to learning to motor
skills to health, etc.…
Yet, we treat sleep as a luxury
rather than as a necessity.
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Sleep Facts
• Adult sleep need is usually 7-9
hours (Homeostatic “set
point”?)
• Impairment in performance
occurs with as little as one or
two hours less per night.
• Sleep debt from restricting sleep
to 5-6 hours a night accumulates
with time.
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Sleep’s demand…
Sleep is mediated by
central nervous
system.
With accumulating
sleep debt, we show
the signs of impending
sleep …
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Chronically Sleep Deprived...
 The average American sleeps fewer than 7
hours
 37% of adults say they are so tired during the
day it interferes with daily activities
 74% of adults experience symptoms of a sleep
disorder a few nights a week or more
 Just one in five adolescents gets an optimal nine
hours of sleep on school nights (High school
seniors – 6.9 hrs/nt)
 College students – 6.1 hrs/nt
NSF Sleep in America Poll
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Are You Sleep Deprived?
1. I need an alarm clock in order to wake up at the appropriate time.
2. It’s a struggle for me to get out of bed in the morning.
3. Weekday mornings I hit the snooze bar several times to get more sleep.
4. I feel tired, irritable, and stressed out during the week.
5. I have trouble concentrating and remembering.
6. I feel slow with critical thinking, problem solving, and being creative.
7. I often fall asleep watching TV.
8. I often fall asleep in meetings or lectures or in warm rooms.
9. I often fall asleep within five minutes of getting into bed.
10. I often feel drowsy while driving.
11. I often sleep extra hours on weekend mornings.
12. I often need a nap to get through the day.
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Sleep Deprivation
Are WWC students sleep deprived?
Sample: 202 students*
• 6.9 hrs/nt
• 29% get 6 hours or less
• 2 out of 3 get 7 hours or less
• 25% feel either “very” or “extremely” tired in
the morning
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*Swoap (2008) WWC Survey,
Consequences of Sleep Loss
Behavioral/Mood
Physiological
Sleepiness / Microsleeps
Psychomotor Impairment
Accidents
Decreased Work Productivity
Reduced Quality of Life
Mood Effects
Deficits in Learning and Memory
Lack of Awareness/Concentration
Substance Use / Abuse
Immuno-compromise
Insulin Resistance
Increase in stress hormones
Blunted Arousal Response (EEG)
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Effects on health:
Institute of Medicine Report
An Unmet Public Health Problem
“The cumulative effects of sleep loss and
sleep
disorders
represent
an
underrecognized public health problem and have
been associated with a wide range of health
consequences including an increased risk of
hypertension, diabetes, obesity, depression,
heart attack, and stroke. Almost 20 percent of
all serious car crash injuries in the general
population are associated with driver
sleepiness. Hundreds of billions of dollars a
year are spent on direct medical costs
related to sleep disorders such as doctor visits,
hospital services, prescriptions, and over-thecounter medications.”
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Effects on health
Dr. Jan Born-- Univ. of Luebeck, Germany
found that people who sleep only 6 hours:
•Have lowered their resistance to viral
infection by 50%
•Produce half the flu fighting antibodies
after a flu shot
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Effects on workers
Up to 70 million working Americans suffer from sleep
deprivation. The cost to businesses is enormous
• increased health care costs
• sleep-deprived workers are responsible for
causing a 250% increase in serious work errors,
many work-related accidents, and increases in
absenteeism and presenteeism
American Institute for Preventive Medicine
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Effects on driving (Jan, 2008)
– Three Florida A&M University students were involved in a fatal
car accident off Interstate 10. The 5:30 a.m. accident on Jan. 6
left two of the students injured and one dead.
Freshmen Antoine Gordon, 18.; Carlos Wilkins, 18; and Cornell
Wedge, 19, were driving back to campus from winter break when
Wilkins fell asleep at the wheel.
Wilkins said once Wedge, who sat in the passenger seat, noticed
Wilkins was asleep he tried to wake him.
However, with the semi truck that rode beside them as well as the
constant nudge from Wedge, Wilkins was startled and lost control
of the Ford Escort. The car veered off the road into a ravine and
hit three trees. Gordon, who was asleep in the backseat with no
seatbelt, died on impact.
Prior to the accident, Gordon's mother said she sensed the group
was tired and insisted they pull over and rest before continuing to
campus. Instead of taking a break, the three students decided to
continue driving.
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“Drowsy Driving”
– Physiological effects (underaroused cortex)
– Poor judgment
– Driving 60 mph… how far do you travel
during a microsleep (4 sec)?
Conservative estimate:
100,000 accidents/yr; 1500+
deaths/yr
Majority occur between 12 & 6 a.m.
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Hours of Sleep and Equivalent Blood
Alcohol Level for Sedative Effects
BrEC, %*
0.190
0.15
0.10
0.05
0.095
0.102
4
2
0.045
Legal Intoxication†
0.20
0.00
6
0
Sleep time (hours in bed)
*Approximate breath ethanol concentration (BrEC) at peak; †Above 0.05% for legal intoxication in many states.
N=32 healthy subjects without prior sleep deprivation and with 85% sleep efficiency. Sleep loss group (n=12)
was tested in all 4 conditions, with 3 to 7 days of recovery time between tests, and compared with ethanol group (n=20).
Roehrs T, et al. Sleep. 2003;26:981-985.
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NSF campaign against Drowsy Driving
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Substance use and sleep
deprivation
The relationship between substance abuse and
sleep disturbance is bidirectional.
• Not only does substance abuse lead to sleep
disturbances, but sleep disturbance can lead to
substance abuse.
• One way that sleep disturbance may create a
pathway for substance abuse is that the
combinations of sleep disturbance, excessive
daytime sleepiness, and poor outcomes, can lead
to self-medication. Students may use stimulants
to increase daytime alertness and alcohol and
marijuana to decrease depressive mood and
sleep problems. Copyright © 2001 by Harcourt, Inc. All Bootzin & Stevens, 2005
Effects on learning
Considerable scientific evidence supports a role
of sleep in memory and learning. Numerous
investigators have reported sleep-dependent
learning across sensory, skill, and motor memory
domains.
Both animal and human studies especially
implicate sleep as important for the process of
memory consolidation following initial learning.
Distinct memory processes may be related to
specific sleep states (i.e., REM) such that sleep
disruption negatively impacts learning.
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Effects on cognitive performance
• Reduced ability to process, concentrate
& remember
• Reduced ability to communicate
1/3/08 Fatigue Factor Gives Equal Time to Candidates (NYTimes)
– Mike Huckabee offered his “apologies” last week over the killing of
former Prime Minister Benazir Bhutto of Pakistan. (He meant
“sympathies,” his campaign clarified.) Sleeping much? “Obviously, I
could use more than I am getting,” said Mr. Huckabee, who is down
to about four hours a night.
– “Senator Barack Obama blamed fatigue for his drastically
overstating the death toll from tornadoes in Kansas in May. He said
10,000 people died. (12 did.)
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Effects on cognitive performance
• Poor decision skills and increased risktaking
• Reduced ability for complex problemsolving (study on REM- vs. NREM-deprived
students)
• Reduced vigilance and increased errors
(study on Marines in training)
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What to do??
• Ingest stimulants? (e.g., Caffeine,
Provigil – the “cognitive
enhancers”)
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What to do??
Take a pill for “perfect” sleep or
find the “perfect” mattress
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What to do, really…
– When we don’t get enough sleep, our
bodies DEMAND it. Listen to that
demand…
– Get out of debt… “sleep debt”
– Sleep hygiene
• Fitness, nutrition, nicotine, caffeine, alcohol,
“worry time,” establish routine cycles (don’t
change drastically on weekends)
• What about naps?
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Sleep Disorders
• 40 million Americans
• Insomnia
– recurring problems in falling or staying
asleep
• Narcolepsy
– uncontrollable sleep attacks
– sufferer may lapse directly into REM
sleep, often at inopportune times
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Sleep Disorders
• Sleep Apnea
– characterized by temporary cessations of
breathing during sleep and consequent
momentary reawakenings
• Night Terrors
– high arousal-appearance of being terrified
– usually in Stage 4, within 2-3 hours of falling
asleep
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Sleep Disorders
• REM Sleep Behavior Disorder (video)
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