Body Rhythms and Mental States

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Body Rhythms and Mental States

• Chapter 5

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Outline of Todays Lecture

• Biological Rhythms
• The Rhythms of Sleep
• Dreams
• Consciousness-Altering Drugs
• Hypnosis

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Biological Rhythms

• A periodic, more or less, regular fluctuation in
  a biological system may or may not have
  psychological implications
• Entrainment The synchronization of biological
  rhythms with external cues, such as fluctuations
  in daylight

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Endogenous Biological Rhythms

• Circadian Rhythms
• Occur about every 24 hours.
• ExampleThe sleep-wake cycle.
• Infradian Rhythms
• Occur less often than once a day.
• Examples include birds migrating, bears
  hibernating.
• Ultradian Rhythms
• Occur more frequently than once a day, about
  every 90min.
• Examples include stomach contractions and
  hormone levels.

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Circadian Rhythms

• Occur in plants, animals, insects and people.
• To study endogenous circadian rhythms, scientists
  isolate volunteers from time cues.
• Supraciasmatic nucleus (SCN)
• Located in the hypothalamus, responsible for
  circadian rhythms by regulating melatonin, a
  hormone secreted by the pineal gland.

Regulates
Neurotransmitters, hormones (e.g.,
melatonin)
SCN
Feedback
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When Internal Clocks are Out of Sync

• Internal desynchronization
• A state when biological rhythms are not in phase
  with one another.
• Circadian rhythms are influenced by changes in
  routine. Examples include
• Airplane flights across time zones.
• Adjusting to new work shifts.
• Also, illness, stress, fatigue, excitement,
  drugs, and mealtimes.

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Moods and Long-term Rhythms

• Seasonal Affective Disorder (SAD)
• A controversial disorder in which person
  experiences depression during the winter and an
  improvement of mood in the spring.
• Treatment involves phototherapy or exposure to
  fluorescent light.
• Evaluating frequency of and treatment for SAD is
  difficult.

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Menstrual Cycles and Mood

• Does the menstrual cycle affect mood?
• People think so. In the 1970s, premenstrual
  syndrome (PMS) came to be thought of as an
  illness and some popular books have asserted that
  most women suffer from PMS

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Menstrual Cycles and Mood

• Physical symptoms are common.
• Cramps, breast tenderness and water retention.
• Emotional symptoms are rare.
• Irritability and depression.
• Fewer than 5 of women have symptoms predictably.

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Research Conclusions about PMS

• No gender differences exist in mood.
• There is no relation between stage of menstrual
  cycle and emotional symptoms.
• No consistent PMS pattern exists across
  menstrual cycles.

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Study Mood Changes in Women and Men
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Why We Sleep

• The exact function of sleep is uncertain but
  sleep appears to provide time for
• the body to eliminate waste products from
  muscles,
• repair cells,
• strengthen the immune system, or
• recover abilities lost during the day.

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Sleep Disorders

• Insomnia
• Difficulty falling asleep or staying asleep.
• Sleep apnea
• Breathing briefly stops during sleep, causing the
  person to choke and gasp and momentarily waken.
• Narcolepsy
• A sleep disorder involving sudden and
  unpredictable daytime attacks of sleepiness or
  lapses into REM sleep.
• Staying up late and not allowing oneself enough
  sleep
• 2/3 of North Americans get fewer than recommended
  8 hours

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Realms of Sleep

• Stage 1. Feel self drifting on the edge of
  consciousness.
• Stage 2. Minor noises wont disturb you.
• Stage 3. Breathing and pulse have slowed down.
• Stage 4. Deep sleep.
• REM. Increased eye movement, loss of muscle tone
  and dreaming.

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Video

• Catching Catnaps

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Dreams

• Do you typically remember your dreams?
• Have you ever been able to control what you dream
  about or how your dream unfolds?
• Have you ever died in a dream?
• Do you have a recurring dream?
• Have you ever had a dream in which one person
  transformed into another?
• Have you ever dreamed of doing something
  impossible (e.g., flying, playing music even
  though you cant)
• Do your dreams often contain inconsistencies
  (e.g., you know it is your house or your room,
  but it doesnt look like it is supposed to)

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Dreams

• 8) Do you ever dream about celebrities?
• Do you incorporate outside noises into your dream
  (e.g., an alarm clock, a telephone ring)?
• Have you ever dreamed about
• Being naked in public?
• Killing someone?
• Finding money?
• Being attacked or pursued?
• Arriving too late for something important?
• Being locked up?
• War?

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Dreams

• Dreams as Unconscious Wishes
• Dreams as Reflections of Current Concerns
• Dreams as a By-product of Mental Housekeeping
• Dreams as Interpreted Brain Activity

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Video

• Dreams Theatre of the Night

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Consciousness-Altering Drugs

• Classifying Drugs
• The Physiology of Drug Effects
• The Psychology of Drug Effects

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Classifying Drugs

• Psychoactive drug
• Substance capable of influencing perception,
  mood, cognition, or behaviour.
• Types
• Stimulants
• speed up activity in the CNS.
• Depressants
• slow down activity in the CNS.
• Opiates
• relieve pain.
• Psychedelic drugs
• disrupt normal thought processes.

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The Physiology of Drug Effects

• Psychoactive drugs work by acting on brain
  neurotransmitters. These drugs can
• increase or decrease the release of
  neurotransmitters,
• prevent reabsorption of excess neurotransmitters
  by the cells that have released them,
• block the effects of neurotransmitters on
  receiving cells, or
• bind to receptors that would ordinarily be
  triggered by a neurotransmitter or a
  neuromodulator.

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The Physiology of Drug Effects
Tolerance Increased resistance to a drugs
effects accompanying continued use as tolerance
develops, larger doses are required to produce
effects once brought about by smaller
ones Withdrawal symptoms Physical and
psychological symptoms that occur when someone
addicted to a drug stops taking it
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The Psychology of Drug Effects

• Reactions to psychoactive drugs depend on
• Physical factors such as body weight, metabolism,
  initial state of emotional arousal and physical
  tolerance.
• Experience or the number of times a person has
  used a drug.
• Environmental setting affects the response to a
  drug.
• Mental set or expectations for drugs effects.

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Hypnosis

• Defining hypnosis
• The nature of hypnosis
• Theories of hypnosis

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Defining Hypnosis

• A procedure in which the practitioner suggests
  changes in the sensations, perceptions, thoughts,
  feelings or behaviour of the participant.

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The Nature of Hypnosis

• The hypnotic state is not sleep.
• Hypnotic responsiveness depends more on the
  person being hypnotized than on the skill of the
  hypnotist.
• Hypnotized people cant be forced to do things
  against their will.
• Feats performed under hypnosis can be performed
  by motivated people without hypnosis.
• Hypnosis does not increase the accuracy of memory

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The Nature of Hypnosis

• Hypnosis doesnt produce a literal
  re-experiencing of long-ago events.
• Hypnotic suggestions have been used effectively
  for medical and psychological purposes.

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Theories of Hypnosis

• Dissociation theories
• Hypnosis is a split in consciousness in which one
  part of the mind operates independently of the
  rest of the consciousness, or
• During hypnosis, dissociation occurs between an
  executive control system in the brain (probably
  frontal lobes) and other brain systems involved
  in thinking and acting.

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Theories of Hypnosis

• Sociocognitive theories
• Effects of hypnosis result from interaction
  between social influence of the hypnotist (socio)
  and the abilities, beliefs and expectations of
  the subject (cognitive).
• Can explain alien abduction and past-life
  regression.