U1b AP Psych In-Class Notes

Biological Rhythms

• Annual  cycles: seasonal variations (bears hibernation, seasonal affective disorder)

• 24 hour cycle: our circadian rhythm

• 90 Minute cycle: sleep cycle

• Monthly cycle: hormone cycle

Circadian Rhythm

• biological clock over 24 hours

• Body temperature and awareness changes throughout the day

• Take a test or study during your circadian peaks

Sleep Stages

• 4 stages of sleep (1-4 = NREM or non-REM)

• Takes about 90 minutes to go through the 4 stages

1. NREM Stage 1

   1. Experienced as falling to sleep

   2. Transition stage between wake and sleep

   3. Usually lasts between 1-5 minutes 

   4. Occupies about 2-5% of a normal night of sleep 

   5. Eyes roll slightly

   6. Feelings of falling or floating

   7. Brief periods of alpha waves, similar to those present while awake

   8. Changes from alpha to theta waves

2. NREM Stage 2

   1. Total theta waves

   2. “Baseline” of sleep

   3. Part of 90 minute cycle 

   4. Occupies about 45-60% of sleep

   5. About 20 minutes

3. NREM Stage 3

   1. “Delta” sleep or “slow wave” sleep

      1. “Slow wave” because brain activity slows down dramatically to a much slower rhythm called “delta”

   2. May last 15-30 minutes

   3. Children can have delta sleep for up to 40% of all sleep time (makes them heavy sleepers)

   4. Growth and rebuilding (of muscles)

   5. Amount of time in this stage decreases over time

   6. Sleeping pills and alcohol prevent you from being in stage 3 sleep

4. REM (rapid eye movement)

   1. Very active stage of sleep

   2. 20-25% of nights sleep

   3. Breaking, heart rate and brain wave activity quicken

   4. Vivid dreams can occur

   5. Paralysis and arousal

   6. REM sleep = dreaming

   7. Know as dream sleeping

   8. From REM you go back to NREM2

   9. More REM the longer you sleep

Sleep Disorders

• Insomnia

  • recurring problems in falling/staying asleep

  • NOT once and a while

  • Not defined by number of hours you sleep ebay night

  • Over a prolonged period of time (at least 2 weeks)

  • Sleeping pills and alcohol prevent you from being in stage 3 sleep

• Narcolepsy

  • Lapses directly into REM sleep (usually during times of stress or joy)

  • Uncontrollable sleep attacks

• Sleep Apnea

  • Temporary cessations of breathing during sleep & consequent momentary reawakening

  • Snoring

  • Many people don’t know they have it

  • associated with obesity

  • Can be subscribed a mask-like device that pumps air into the lungs (CPAP)

  • Many different types (we’re only talking about general)

• Night Terrors

  • High arousal and appearance of being terrified

  • Happens in NREM 3 and are not often remembered (NOT REM)

• Sleepwalking

  • Happens during NREM 3

  • Young children are most likely to experience both night terrors and sleepwalking

  • Usually harmless and unrecalled the next morning

  • Its not dangerous to awaken a sleepwalker but they do become confused or disoriented after awoken

Ways to get better sleep

• Stop using screens/phone before bed (at least ½ hour)

• Only sleep in your bed (conditioning)

• Let your mind wander (give yourself time to think, walking dog, meditation, cleaning, exercise)

• Consistent bed time

• Don't drink caffeine or eat at least 3 hours before you eat

REM Rebound

• REM tends sleep tends to increase following REM sleep deprivation

• You have more dreams when you are sleep deprived (instead of deep NREM 3 sleep)

Lucid dreaming

• You know you are dreaming (can sometime control the dream)

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• Conscious suggestion to the unconscious dream to dream about a certain thing

Theories of dreaming: Why do we dream?

1. Freud’s wish-fulfillment theory

   1. Dreams are meant to satisfy our own wishes

   2. The key to understanding inner conflicts

   3. Ideas and thoughts hidden in our unconscious

   4. Manifest and latent content

2. Activation-Synthesis Theory

   1. Dreams are your brain's way of trying to make sense out of random neural firings

   2. Limbic system (emotion) and visual cortex have increased activity while dreaming

   3. Signals start in the pons

   4. Random bursts of neural activity, dreams is your brains trying to make sense of it

   5. Controversial because people want to think that their dreams aren’t meaningless as this suggests  

3. Information-Processing Theory

   1. Dreams are meant to file away memories

   2. Those deprived of REM sleep do worse learning than those sleeping undisturbed

   3. Helps with memory processing

4. Physiological Function Theories

   1. Regular brain stimulation from REM sleep may help develop and preserve neural pathways

   2. Neural health and REM sleep/dreams are correlated (not proved though)

5. Cognitive Development

   1. Reflects dreamers cognitive development

   2. Children under 9: dreams are like slideshow

   3. Older: Coherent storylines where we are actors

How to remember dreams:

• Dreams comes from pons and through cerebral cortex so they fade fast

• Have it next to bed and write down right away

• Catch yourself not during REM sleep 

• Set an alarm for middle of the night

• Old sleep times

• Second sleeps

Two sleep theory

Sensation: your window to the world (unassembled lego bags of random pieces, collect light and sends to brain)

• Bottom-Up processing

  • Analysis that begins with the sense receptors and works up to the brain’s integration of sensory information

• Top-down processing

  • Information processing guided by higher-level mental processes

    • As when we construct perceptions drawing on our experience and expectations

  • Inferring, guessing, using context clues

• Thresholds

  • Absolute Threshold

    • Detects 50% of the time

  • Signal detection theory

    • Predicts how and when de detect the presence of a faint stimulus with background noise going on

    • Detection depends on experience, expectations….. More on slides

  • Subliminal stimulation (stimuli below a persons threshold for conscious awareness)

  • Difference threshold: minimum difference between two stimuli to detect 50% of the time

    • Just noticeable difference (JND)

    • 500L vs 501L lightbulbs

    • 85db vs 85.1db difference (you can’t notice the difference)

    • 3lb weight vs 3lb weight plus a paper clip

  • Webers law: 

    • Constant minimum percentage required

    • To perceive two stimuli as different

    • Named after ernst weber

• Sensory adaptation

  • Decreased responsiveness to stimuli due to constant stimulation

• Cocktail-party phenomenon: ability to focus on one’s listening attention of a single talker among a mixture of conversations and background noises ignoring other conversations (type of selective attention)

• Energy v. Chemical senses

  • Chemical (tasting or smelling)

  • Energy (sound waves, touch)

• TRANSDUCTION (translation)

  • The brain communicates and thinks with electrochemical/neural impulses (not light, not sound waves)

  • Translates sensory data to neural impulses

  • Thalamus

VISION

• Visual capture (brain prioritize visual data over everything else)

• Most dominating sense

• Phase One: Gathering light (electro magnetic spectrum)

• Shorter wavelength more purple, longer (lower frequency) wavelength redder collor

  • Troughs and tips

  • Length of wavelength gives us its color

• Trichromatic Theory

  • Three types of cones: blue, green, red light

  • Can make millions of different colors

• Opponent-Process Theory

  • Red/green

  • blue/yellow

  • black/white

  • If one color is stimulated, the other is inhibited

  • Afterimages

HEARING

• Sound travels in waves

• Frequency gives us pitch

• Height of wave gives us amplitude of sound

• Long wavelength (lower frequency)

• Transduction in the ear

  • Sound waves hit the eardrum 

  • The hammer vibrates

  •  The anvil vibrates

  •  The oval window (the place where the stirrup meets the cochlea receives the sound waves

  • The cochlea is lined with mucus called basilar membrane

  •  In the membrane there are hair cells

  •  The hair cells vibrate 

  • Tryn into vibrations into neural impulses called the organ or corti

  • Place theory (go back and summarize explanation)

  • Frequency theory (go back and summarize explanation)

  • Pitch theory (summarize)

• Deafness

  • Conduction deafness

    • Something goes wrong with the sound and the vibration on the way to the cochlea

    • You can replace the bones or get a hearing aid to help

  • Nerve (sensorineural) deafness

    • The hair cells in the cochlea get damaged

    • Loud noises can cause this type of deafness

    • NO WAY to replace the hairs

    • Cochlear implant is possible

TOUCH

• Receptors located in our skin

• Gate Control Theory of Pain (summarize)

TASTE

• We have bumps on our tongue called papillae

• Tast buds are located on the papillae (they are actually all over the mouth)

• Sweet, sour, salty, umami, bitter

SMELL

• Goes through our hippocampus

• Tied to memory

Perception: interpreting what comes in your window (puts legos together, constructs reality)

Actual clouds rather than the images inside of clouds