AP Psych Unit 1 (part 3)

Deep sleep 

Breathing + heart rate slow, body repairs tissues, bones, muscles, and consolidates memories, 3rd stages of NREM sleep / slow-wave 

Consciousness

Level of awareness of ourselves and our environment (high levels = awake) 

Pre conscious

Bringing back awareness (ex: memories you can easily recall when prompted- recalling a dream)

Non conscious

Mental processes that are inaccessible to our awareness, automatic + involuntary functions (ex: heartrate)

Unconscious

Completely unaware (drug induced anesthesia, coma, takes an outside effect) 

Hypnosis

Altered state of consciousness, heightened suggestibility + focused attention, person becomes more receptive to suggestions 

Sleep wake cycle

Circadian rhythm- natural 24-hour pattern of wakefulness and sleep regulated by brain's master clock, daylight promotes wakefulness + darkness triggers the production of melatonin 

Ultraradian cycles

Biological cycles that occur more than once within a 24-hour period (ex: 90 min cycle sleep stages, REM + NREM) 

Infradian cycle 

Biological cycle that occurs over a period longer than 24 hours

NREM

Non-rapid eye movement- first 3 stages of sleep (slower brain waves, heart rate, breathing, body repairs)

Stage one

Lightest stage of sleep- transition from wakefulness to sleep, hypnagogic sensations (drifting off)

Stage two

Period of light sleep- brief bursts of brain activity called sleep spindles occur, heart rate + breathing slow further, body temperature drops 

Stage three

Slow-wave or deep sleep- body repairs tissue, bone, muscle, strengthens immune system, slow brain activity waves, significantly slowed heart rate + breathing 

Hypnagogic sensations

Vivid, dream-like experiences that occur as a person is falling asleep including seeing, hearing, or feeling things that aren't there (ex: sudden feeling of falling, visual flashes / patterns, hearing voices) 

REM

Rapid eye movement- increased brain activity, dreaming, body temporarily paralyzed, paradoxical sleep, breath increases, brain goes into hyper activity 

Paradoxical sleep

Prevents the body from acting out dreams (temporary paralyzation)

REM rebound 

Brain making up for lost sleep / more frequent REM sleep towards the second half of sleep, counteracts irritability, fatigue + alertness

Insomnia

 Inability to sleep well at night (caused by depression, anxiety, stress, diet, bad sleep schedule, + genetics)

Narcolepsy

Lapsing into REM sleep at random times (caused by genetics)

Sleep apnea 

Breathing briefly stops because the medulla fails to continue breathing during sleep, keeps the person in stages 1 + 2 of sleep (treated with a CPAP machine) 

Somnambulism

Sleepwalking- the cortex shuts down but the cerebellum is still active (walking without thinking about walking) 

REM behavior disorder

Act out dreams because paralysis stops happening during REM sleep

Dreams

Produce images, sensations and perceptions in storylike form during REM sleep, Freud believed dreams had very specific and significant meanings to address certain traumas 

Lucid dreams 

The state of being aware that you are dreaming while still in the dream

Consolidation theory

Belief that dreams are a psychological function, brain is restructuring itself during dreams and we see things happen as memories are being stored, organized + created 

Activation synthesis theory

Belief that dreams are the cerebral cortex's attempt to make sense of random neural signals that originate from the brainstem during REM sleep

Recurring dreams

Repeated dreams with similar themes, often occur when your brain is trying to process an unresolved issue, stress, unmet psychological needs 

Sensation

The process by which we receive information from the environment

Perception

The interpretation of information from the environment so that we can identify its meaning 

Transduction

Conversion of certain stimuli / energy into something our brain can translate 

Sensory adaptation

When sensory receptor cells are constantly stimulated they undergo a loss of sensitivity to stimuli (house smell)

Just noticeable difference 

The smallest difference two stimuli that can be consistently and accurately detected 50% of the time 

Weber's law

The greater the initial intensity of a stimulus the larger the change must be for a person to notice the difference 

Synesthesia

Your brain routes sensory information through multiple unrelated senses causing you to experience more than one sense simultaneously (hearing music - seeing colors) 

Perceptual set

Our expectations influencing our experience

Accommodation

The lens changes to allow focus of near or distant objects onto the retina, the image of what you see is being projected upside-down 

Optic nerve 

Bundle of nerve fibers that transmit visual information from the retina to the brain, tied into ganglion cells (the string connected to eye) 

Photoreceptor cells

Cones and rods

Cones

Responsible for color vision in bright light, 3 types of cones- (short/blue, medium/green, + long/red) enable us to distinguish different colors, concentrated in the fovea 

Rods

Enable vision in low light, responsible for peripheral vision + detect motion, only in shades of gray

Photosensitivity 

The ability to perceive light

Bipolar cells 

Transfer information from rods + cones to ganglion cells, 10^o off the center 

Ganglion cells

 Transmit electrical signal to the optic nerve 

Retina

Light-sensitive layer of tissue at the back of the eye that converts focused light into neural signals, which are sent to the brain by the optic nerve to be interpreted as images

Blindspot

Small spot in vision where your eye is filling in the blank spot to make it consistent for your brain (made from there being no cones + rods on the optic nerve) 

Absolute threshold 

Bare minimum needed of stimuli that can be detected 50% of the time 

Trichromatic theory

Human eye has three types of cone cells, each sensitive to different wavelengths of light (red, green, + blue)

Opponent process theory 

Certain cells get fatigued after looking at a specific color in lighting situations so when red is being perceived then it goes away you see green (blue + yellow, black + white) 

Monochromatic

Seeing only shades of grey

Dichromatic 

Only two types of cone cells are functional (most commonly red + green) 

Afterimages 

Things that are designed to show opponent processing theory

Prosopagnosia

 Inability to recognize faces, damaged temporal lobe

 Blindsight

Individuals with damage to their primary visual cortex can respond to visual stimuli in their blind field without conscious perception (