SLEEP AND WAKING - CHAPTER 11

Biorhythms

3 Categories

• Infradian
  • Less than once a day
  • Menstrual cycle
• Circadian
  • Sleep wake cycle
  • Coordinates biochemical, physiological and bx
• Ultradian
  • More than once a day
  • Sleep cycle
• Zeitgebers: external cue that biorhythm depends upon
  • Natural light, clock
• Free running circadian: absence of zeitgebers
  • Biosphere study: Environment with only artificial lighting and no clock
    • Sleep wake cycle gets long
  • Someone who is completely blind or working in coal mines or submarines can have some sleep disorders
• Entrainment: Reset
  • Impact of light deprivation
    • No reset

Individual Variations in Sleep Patterns

• Morning (lark) vs. evening (night owl) people
  • Positive emotions and subjective well-being higher in those who are morning ppl
• Adolescence shift → much more likely to be night owls
  • Tend to have lower levels of Melatonin
  • Mature brain is much more likely to be a morning person/ more alert

Shift Work: work schedule is at odds of general sleep wake cycle (2nd or 3rd shift)

• Shift maladaptation syndrome
  • Disturbed sleep for evening and night shift workers
  • Health, personality, mood, and interpersonal problems
  • Accident rates higher
  • Lark vs. night owl
    • 2nd shift night owls are better off than larks
    • 3rd shift is bad for everyone
      • Worse if work schedule varies

Jet Lag, and Daylight-Saving Time

• Jet lag
  • Conflict b/w zeitgeber and interal clock
  • If gained time then it isnt really a problem, but if you lose time then symptoms are more present
  • Fatigue, irritability, sleepiness
• Daylight saving time
  • Symptoms of jet lag
  • Risk of heart attack

Body’s Internal Clocks Manage Circadian Rhythms

• Suprachiasmatic nucleus (SCN) (master clock)
  • Keep circadian rhythm
  • Oscillation of protein production and degradation is a mechanism that allows the brain’s master clock tell time
• Intrinsically photosensitive retinal cells info to SCN → melanospin (photopigment)-light receptor cell
• SCN >>> SNS >>> pineal gland>>> melatonin
• Regulation by SCN
  • Body temp, hormone secretion, urine production, blood pressure
  • Can adjust to a phase shift → daylight savings, difference in sleep from weekdays to weekends
  • SCN (1-2 cycles) vs. peripheral clocks (take longer)

Biochemistry of Circadian Rhythms

• Melatonin
  • Starts to increase at 10 or 11am
  • Peak at 4 AM
    • 2nd peak?
      • May have another around 3-4 pm
  • Effects
    • Pineal gland tumors, constant exposure to light, melatonin supplements, immune system (stronger w proper amounts)
• Cortisol
  • High in morning, low at night
  • Effects on heart rate, blood pressure, energy
  • Impact of crossing time zones

Neural Correlates of Waking and Sleep

Electroencephalogram (EEG) Recordings of Waking and Sleep

• Desynchronous: independent action
• Synchronous: dependent action (unison) → deep sleep

—--Waking

• Typically alternate between beta and alpha

Brain Wave Frequencies

• Gamma – greater than 30 cps (cycles per second) → “in the zone”
• Beta – 14-30 cps → alert, focused
• Alpha – 8-13 cps → relaxed wakefulness
• Theta – 3-7 cps → light sleep (still have some awareness of outside world)
• Delta – less than 3 cps → deep sleep

Sleep Cycle

• Sleep (90-120 minute cycles)
  • 1 NREM (theta, 10-15 minutes, SNS slows)
  • 2 NREM (theta/sleep spindles/K-complex, 15 minutes, 50% of sleep, SNS)
    • Sleep spindle: sudden burst of activity, happens every 14 seconds
    • K-complex: opposite of sleep spindle, (single delta wave)
  • 3 NREM (theta/20% delta, 5-40 minutes): deep sleep
  • REM (beta/theta, SNS active but major muscle paralysis)
    • Breathing and heart rate increase

Brain Networks Control Waking and Sleep

• Default mode network (DFN)
  • Mind wandering/daydreaming → unfocused thought
  • 50% of time awake in DMN
  • Inverse relationship between focused activity & DMN
• NREM Sleep networks
  • Preoptic area (POA) of hypothalamus → (homeostasis)
  • Monitors sleep debt (duration & intensity of sleep)
    • Consistent sleep deprivation
  • Electrical stimulation of POA produces immediate NREM sleep
• REM Networks
  • Pons active during REM
  • Pons also responsible for muscle paralysis and REM movements
  • Frontal lobe → inactive
  • Hippocampus → more active, impact dreams
  • Amygdala → more active, emotional (fear)
  • Anterior cingulate cortex → active, pleasure

Biochemical Correlates of Waking and Sleep

• Adenosine
  • Builds up during wakefulness
  • Gradually drops during sleep
  • Caffeine blocks adenosine receptors
• Melatonin
  • Onset of dark cycle
  • Surge before “opening of sleep gate” → right before you fall asleep

Functions of Sleep

Changes in Sleep over the Lifetime

• • Infants (newborn/1st month)
    • 12-16 hours total sleep, 50% REM, more w premature
  • Up to 12 months
    • 13 hours total sleep
  • 1-5 years
    • 8.7 hours, higher delta (very deep sleep) wave time 3-6yrs
      • More deep sleep than any other age
  • Puberty
    • Want more sleep (9-10 hours), less delta
  • 50’s and older
    • Lose 27 minutes oer decade, less delta
    • Calcification of pineal gland (less melatonin), less sleep spindles (sudden burst of activity during 2NREM)
      • Impact quantity and quality of sleep
    • Elderly adults may produce less melatonin bc of calcification of the pineal

EFFECTS OF SLEEP DEPRIVATION

• Hallucination after 72 hours
• Longest someone stayed awake was 11 days (recovered fine)

Possible Advantages of Sleep

• Safety
  • Impact on amount of sleep
    • We have a safe environment to sleep
    • Horse gets least amount of sleep
      • No protection other than running
    • Sloth gets most sleep
      • Safe in trees
• Physical restoration (NREM)
  • Restores body, conserves energy
    • Immune system, healing (cannot heal wounds when sleep deprived), neurogenesis (creation of new neurons), joint/muscle pain
  • Animals >>> metabolism >>> sleep
    • Animals that have a faster metabolism → more sleep
  • Human growth hormone (GH) (stage 3)
• Memory consolidation
  • NREM (verbal)
  • 2 NREM (procedural→ tasks)
  • REM (emotional)
• Special Benefits of REM Sleep
  • Mammals and birds
  • Increases after learning
    • Studying before sleeping
  • Changes over lifespan (brain development)
    • More REM as infant (exposed to many stimuli)
    • 2-4 yrs → overproducing synapses
  • REM deprivation
    • REM rebound
      • We have more REM when we have learned something that day
    • Irritability
    • Difficulty concentrating

Possible Functions of Dreaming

• REM & DMN continuum
  • Daydreaming is positive, provides relief

3 reaons why we dream:

• Activation-synthesis theory
  • What we dream about reflects the specific area of our brain that was active
• Neural network model
  • Dream to try to forget info that is irrelevant
  • Mental house keeping theory (deciding what memories to keep)
• Evolutionary model
  • When stressed → dream more
  • Amygdala more active during dreaming
  • Falling or flying dream – vestibular system is overactivated
• Lucid dreaming
  • Control of dreams
  • 55% of adults have had a lucid dream
  • Can train yourself
    • Have dream journal
  • Athletes trained
    • They were supposed to have a dream about exercising
      • Those who dreamt exercise showed some muscular development
• Nightmare
  • During REM
  • Negative intense emotional dream (story/theme)
• Sleep (night) terror
  • Typically delta (deep sleep, stage 3)
  • Random scary thought

Sleep-Wake Disorders

Major Depressive Disorder with Seasonal Pattern (seasonal affective disorder)

• Person mets criteria for major depression (5 symptoms for 2weeks, disruption of life)
• Cause: insufficient amount of daylight
  • Decrease in serotonin–precursor to melatonin) → less melatonin
  • Genetic variations
    • Melanopsin
• Treatment
  • Light therapy
  • Impact of timing of light therapy
    • Hard time waking up in morning →use in morning

Insomnia

• Most common sleep disorder
• Role of stress
  • Stress is the most common cause
  • Cant shut off the mind when wanting to sleep
• Onset
  • Difficulty falling asleep
    • Longer than 15 min to fall asleep when tired (episode can occur)
• Maintenance
  • Fall asleep okay but can not stay asleep
• Pseudo insomia
  • False
  • States that they can not fall asleep
  • But when in sleep study they are asleep
    • Dream that they are awake
• Tx
  • Natural
    • Sleep hygiene
      • Sleep at same time
      • Avoid screen time
      • No caffeine before sleep
      • Avoid exercise before sleep
      • Get up at the same time
      • Bedroom is really only for sleep
  • Medical
    • Ambien
    • Melatonin
      • Go to bed later, when actually tired → reset circadian rhythm

Narcolepsy

• Sleep attack → fall asleep without intending to
• Fairly brief
  • 10-20 min
• Happens every 2-3 hrs
• Results from disruptions in the synthesis of receptors for orexin
• Episodes
  • Immediate REM sleep
    • Muscle paralysis
  • Additional symptoms
    • Sleep paralysis
    • Dream while awake
      • Hypnagogic: dreaming before falling asleep
      • Hypnopompic: dreaming after “waking”
    • Muscle paralysis while awake → cataplexy
      • Warning for episode

Breathing-Related Sleep Disorders

• Obstructive sleep apnea (hypopnea—shallow breathing)
  • Stop breathing / pathways close
  • 100s of episodes in the night
  • Intense snoring
  • Sleep on back, overweight, more common in males, increased risk of heart disease and strokes
  • Breathing machine tx
• Central sleep apnea
  • Area of brain that controls breathing (medulla) does not function properly during sleep
  • 1-2 min
  • Possibly stimulation of brain for tx

SIDS (Sudden Infant Death Syndrome)

• Ages 2-4 months
• Position for sleeping
  • On their back, in their crib
• Breastfeeding
  • Lower risk of SIDS if child is breastfed, opposed to bottle fed
• Cigarette smoke
• Overcrowding
  • Environment, crowded apartment, lots of stuff in baby bed (increases risk)
• Winter
  • More likely to happen in^ also in a premature birth

Sleep talking (Somniloquy)

• Age
  • More common in grade school to high school
• Happens in the lighter stages of REM & NREM
• Respond to external stimuli

Sleep walking (somnambulism)

• Most common in 4-12 year olds
• Delta NREM (deep sleep)
  • Routine activity
• Genetic link
• Can increase with stress

REM Sleep Behavior Disorder

• Lack of paralysis
  • “acting out dreams”
• Inherited or brain damage (pons)

Restless Leg Syndrome (RLS)

• Regular movements during sleep

CHAPTER 14 - SOCIAL & AFFECTIVE NEUROSCIENCE

Components of Emotion

• Physiological
  • Heart rate, breathing, body temp
• Behavior
  • Facial expression, interact w someone else
• Thought
  • Ideas, beliefs, influence emotion, perspective will have significant impact
• Conscious, subjective experience
  • Emotions are personal
  • Worse if message (“you shouldn’t feel that way”) is received by child → child will doubt emotions

Evolution & Adaptive Benefits of Emotion

• Energy creation
  • Emotions help with general arousal, and ability to respond
• Yerkes-Dodson
  • Want a moderate amount of anxiety
• Direction of movement
  • Positive (toward)
    • $5 on sidewalk
  • Negative (away)
• Emotions and nonverbal communication
  • Facial expression (survivial value)
    • Guides bx (from own expression and others)
      • Threat detection
  • Body language

Models of Emotion

• James-Lange Theory of Emotion

STIMULUS >>> autonomic nervous system (ANS) AROUSAL >>> EMOTION

• • Imitation of facial expression & empathy
    • Imitating facial expressions increases empathy
  • Catharsis
    • Purging of emotion
    • Rumination
      • Sitting in one’s own thoughts and feelings (bad)
  • Flaw to theory
    • Not distinct physical sensation for each emotion
    • Example for “crossing the bridge” study
      • Male participants interviewed by female interviewer
        • Control: at the park
        • Tx: on a high suspension bridge
      • The tx group attributed the increase in heart rate being attracted to the interviewer
• Cannon-Bard Theory of Emotion
  • Stimulus → ANS arousal and feeling
    • Simultaneously
    • independent
• Schachter-Singer Two factor Theory of Emotion

Stimulus → ANS arousal → Cognitive apprasial → feeling

• Cognitive appraisal
  • Why is the ANS aroused
    • Dog chasing you → heart rate increase → my dog? Random dog? → happiness or fear

Contemporary Theories of Emotion

• Use both James-Lange & Schachter-Singer
  • James-Lange
    • Precise physical sensation
    • Immediate reponse
  • Schachter-Singer
    • Ambiguous physical sensation
    • Delayed response
• Somatic markers
  • Feeling associated with paricular/ prior experience
  • Subjective feeling mapped as positive/ negative

Controlling Facial Expression

• Use whole body
  • Emphasis on face (especially eyes), face module infants
    • Begins in infancy
      • Programmed to pay attention to faces
• Cranial nerves
  • Facial nerve
    • Superficial nerves (skin, facial expression)
  • Trigeminal nerve
    • Deeper nerves (bones of the head, chewing food & speaking)
• Upper vs. lower facial nerves (impact - damage to nerves)
  • Upper third bilateral control
  • Lower 2/3rds contralateral
• Major pathways
  • Primary motor cortex
    • Voluntary, volitional facial paresis
      • A person asks you to smile
  • Subcortical system
    • Spontaneous, emotional facial paresis
      • Something is humerous

Biological Contributions to Emotional Expression

• 8 basic emotions & expressions
  • All cultures and throughout time
• Impact of blindness
  • Blind individual still expresses emotions
• Impact of isolation
  • Still express emotions

Environmental Contributions to Emotional Expression

• Training
  • Show or not show emotions
  • Doctor
    • Regulate emotions to keep patient calm
• Presence of others
  • More intense positive emotions when with others
  • Less intense negative emotions when with others
• Cultural display rules
  • Japanese vs. American
  • Americans are more open to show emotions/expressions in public
  • Japan is taught to regulate emotions in front of other people/ in public
    • Increase in emotions when alone

Individual Differences in Emotional Expression & Recognition

• Begins in infancy
• Highly reactivity to environmental stimuli → difficult temperment
• Extremely low reactivity to environmental stimuli → slow to warm up temperment
• Disorders associated with low ability to understand facial expression
  • Antisocial personality disorder
  • Schizophrenia
  • autism

Lie Detection

• Signs
  • Change in body movements
  • More “um” and “uh”
  • Less story detail
  • Tell story backwards
    • Validate story
  • No Duchenne smile
    • No eye movement/expression during smile
• Polygraph
  • Respiration, sweating, blood pressure

Autonomic Nervous System & Emotion

General arousal

• Areas of the brain & emotion
  • Amygdala
    • Initiates arousal, and processes stimuli
    • Fear, anxiety, and aggression
    • Lesion vs stimulation
  • Insula
    • Where frontal and temporal lobe
    • Discriminate between positive and negative stimuli
  • Anterior cignulate cortex
    • More conscious appraisals about threat
    • Information about physical pain, reward, and decision making
  • Basil ganglia
    • Recognizing facial expression (disgust)
      • Most people have asymmetrical faces
    • Coordination of movement
      • Respond to emotional stimuli
  • Cerbral cortex
    • Forntal lobe and anxiety
      • When we think about events with anxiety, levels of anxiety decrease
        • Planning
    • Left cerbral hemisphere
      • Processes more positive emotions
    • Right cerebral hemisphere
      • Processes more negative emotions
      • Focus more positive/gratitude→easier to remember positive events
    • Lateralization of right cerebral hemisphere
      • Overall, right processes more emotions than the left
      • Naturally focus more on the negative
        • Negative emotions tend to be more powerful→ tendency to focus on the negative
• Patterns of activation & emotion
  • Widespread area of brain
• Stress and stressors
  • Stress: unpleasant and disruptive state from the perception of danger (state of needing to adjust)
    • Eustress: “the spice of life”; type of stress that + your ability to function. Positive short term stress, helps you get stuff done, beneficial
    • Distress “kiss of death”; a state in which your ability to function is compromised
  • Event itself
    • Major event (new job, death, marriage)
    • Daily hassle (minor, common occurrence
      • Accumulcation can be very stressful
        • Can be more stressful than major event
    • Conflict
      • Approach-approach
        • 2 opinions, like both
      • Avoidance-avoidance
        • 2 options, you dont like either one
      • Approach-avoidance
        • 2 options, like 1 don't like 1

Situations w positives and neg

Stress- Hans Selye & General Adaptation Syndrome

• Walter Cannon’s fight-or-flight
  • Quick, immediate response to stressor
  • (tend & befriend)
    • Stressor → seek support from others
    • Females more likely to respond this way
    • Males protectors → fight or flight
    • Females nurture → seek support
• Selye’s theory
  • Alarm
    • Fight of flight (is just the first stage)
  • Resistance
    • Continue coping
  • Exhaustion
    • Energy depleted

Responses to Stress

• Coordinate physical, cognitive, and behavioral
• Activation of SNS
• Hypothalamus activates endocrine system
• Use energy to flee or fight

Stress & the Amygdala

• Helps with determining threat
• Thalamus >>> amygdala (emotion of fear)
• Thalamus >>> cortex (determine cause of fear) (C→C)

Stress, SAM, & HPA

• Sympathetic adrenal-medullary
  • Hypothalamus >> SNS >> adrenal (adrenaline & norepinephrine)
  • Immediate response, short-lived
  • Fight or flight response
• Hypothalamic-pituitary-adrenal axis
  • Amygdala >> hypothalamus (corticotrophin-releasing hormone & vasopressin) >> pituitary (adrenocorticotropic hormone) >> adrenal (cortisol)
  • Slower, last longer (cortisol 3 hours)
  • Hippocampus – inhibit CRH if too high
• Stress and immune system
  • SAM → immune system is enhanced
  • HPA → immune system is supressed

Stress & Epigenetics

• Highly attentive rat mothers
  • Sensitive to cortisol levels
    • Respond appropriately; beneficial
  • Lower hormonal and bx response
• Low attentive rat mothers
  • Low sensitivity to hormone levels
    • Much longer time for those hormone levels to return to normal
    • Not licking, not nurturing

Stress, the Immune System, & Health

• Stress hormones
  • Suppress activity of lymphocytes
• B lymphocytes (vaccinations)
  • Release antibodies, programmed to fight specific antigens
• T lymphocytes
  • Cancer cells and other antigens
• Type A vs. Type B
  • Type A: competitive, time conscious, productivity, difficulty relaxing
    • Cynical, chronic hostility (i.e, road rage)
    • Greater health problems
  • Type B: laid back, eb n flow
• Chronic stress
  • Greater suppression of immune system
  • Cortisol
    • Increase blood pressue
    • Increase fat release

Aggression & Violence

• Types of aggression
  • Premeditated: planning, proactive (youre the one who starts it)
  • Impulsive: hot aggression, reactive (someone else has initiated and we respond)

Genetics, Environment, Epigenetics, & Aggression

• Genetic link
  • Aggression can be bred
    • “Bull” breeds
  • Heritability of impulsive agression
• Epigenetics
  • Interaction b/w levels of monoamine (dopamine) oxidase A & child maltreatment
    • Low levels of enzyme & high levels of child maltreatment → antisocial bx
    • Low levels of enzymes & NO child maltreatment → no antisocial bx
• Environment
  • Breakdown of social institutions (marriage)
    • Culture where divorce is common and not stigmatized
    • Focus on function of partents after divorce (parenting)
  • Community support
    • As communities are getting more crowded, people are keeping to themselves

Brain Structures and Aggression

• Hypothalamus
  • Stimulation of medial (violent) vs. lateral (hunting)
  • Removal of cerbral cortices
    • Inhibit hypothalamus → “sham rage” (violent, uncontrolled, undirected rage)
• Amygdala
• Anterior cingulate cortex
  • Inhibit aggressive bx
  • Lesion→ can not inhibit
• Orbitofrontal cortex
  • Inhibit aggressive bx
  • Lesion→ can not inhibit

Biochemistry & Aggression

• Alcohol use
  • Alters ability of ACC & OFC to inhibit aggression
  • “Agreesive drunks” know what to watch out for
• Testosterone
  • Increase reactivity to threats (males & females)
  • Rats (castrated or adminstered)
• Serotonin
  • Facilitates activity of ACC & OFC
  • Encourage empathy?

Pleasure & Reward (From Chapter 9)

• Classical Research in Self-Stimulation
  • Olds & Milner (1954)
    • Wire electrode in rat’s brain
      • Can reward self
    • Intracranial self-stimulation (ICSS)
      • Would spend most time rewarding self
  • Routtenberg & Lindy (1965)
    • 2 levers (food or ICSS)
    • Choice of ICSS
      • Would starve self
  • Humans- septal area of brain (reward center)
• Rewards Pathway
  • Natural stimulation of area
    • Eating, sexual activity
  • Unnatural behaviors
    • Gambling >>> eating
  • Dopamine
    • Amount released
    • Amount of blocking
• Cortical Processing of Reward
  • Ability to delay gratification
    • Distant vs. immediate
    • Much more successful if can delay
  • Implication of anterior cingulate cortex
    • Cost-benefit decisions (assign value)
  • Orbitofrontal cortex
    • Damage leads to poor decisions
    • Linked to antisocial personality disorder (not thinking about consequences)
  • Prefrontal cortex
    • Reduces impulses