ap pysc
Sleep
Consciousness = is our awareness of ourselves and our environment
2 types of consciousness:
Wakefulness = when we are awake, aware of surroundings, think, feel and react
Sleep = not fully aware of surroundings, but brain is on and can process things like sounds
Cognitive Neuroscience - how brain activity is linked with cognition
Circadian rhythm - biological clock that is a 24 hour cycle
involves changing your blood pressure, internal temperature, hormones and regulating your sleep wake cycle
Jet lag - Can become disrupted - change to working the night shirt or travel to different time zones - your clock will become out of sync with the local time; causes individual to feel tired, disoriented and sluggish
EEG - allows us to measure the frequency of waves (the number of wakes per sec) and the amplitude (size of wave)
Types of brain waves
Delta - deep sleep
Theta - drowsy
Alpha - relaxed - slower waves with high amplitude
Beta - focused - low in amplitude with the fastest frequency - usually when you are engaged in something (baseball)
Stages of sleep
NREM stage 1
Lasts about 5-10 mins
Body will start to relax and your mind starts to slow
Common waves = alpha waves
Hypnagogic Sensations - experience sensations that you imagine are real, when you are in light sleep (fall from a dream)
NREM stage 2
Lasts 10-20 mins
K-complexes and Sleep spindles (which are bursts of neural activity)
Common waves = theta waves
NREM stage 3
Deepest stage of sleep
Lasts 30 mins
Growth hormones are produced
individual may experience sleepwalking or sleep talking
Common waves = delta waves
REM sleep (rapid eye movement)
External muscles = paralyzed
Internal muscles = active
Common waves = Beta waves
Lasts for about 10 minutes
Experience dreams or nightmares
Considered paradoxical = brain waves are similar to wakefulness, but the body is at its most relaxed
As sleep cycle progresses, REM stage becomes longer
If you keep getting woken up and never get to REM sleep = REM deprivation, which could cause REM rebound → next time you get REM sleep, reach it more quickly and spend more time in REM
Theories of trying to understand dreams
Activation-Synthesis Theory - takes the perspective that dreams are the brain's way of making sense of random neural activity during sleep
Consolidation theory - takes the perspective that dreams help process and strengthen our memories and experiences
Restoration Theory - believes that we sleep b/c we get tired from daily activities and we sleep to restore our energy and resources
Insomnia - sleeping disorder where an individual will have trouble falling asleep or staying asleep
Can be caused by stress, pain, medication or irregular sleep schedule
Sleep Apnea - when an individual has a hard time falling asleep or staying asleep b/c they are struggling with breathing
REM sleep behavior disorder - person acts out their dreams during REM sleep
Somnambulism (sleep walking) - this a disorder where a person gets up and walks around while still sleeping (stage 3)
Night Terror - experience intense fear while sleeping (nightmare)
Narcolepsy - individuals will struggle to get sleep at night and will uncontrollably fall asleep during the day
Sensation
Sensation = the process of detecting information from the environment
Sensory Transduction - taking in an outside stimulus through one of your senses you activate sensory neurons, creating a sensation
You must hit an Absolute threshold to experience a sensation - smallest amount of stimulation needed for you to notice a sensation at least 50% of the time
Sensory adaptation - happens when we have a stimulus that is continuous, and doesn't change (candle)
Habituation - when you are repeatedly exposed to stimulus and start to have a reduced response to the stimulus (drugs)
Difference Threshold - the minimum change between 2 stimuli that causes an individual to detect the change (outside temp vs. inside temp)
Weber-Fechner-Law = is the idea for us to notice a difference between 2 stimuli, the 2 stimuli must differ by a constant percent = not a constant amount
Sensory Interaction - when are sight, hearing taste, smell, and touch work together
Synesthesia - is a neurological condition where one sense is experienced through another (might see color when they hear music)
Visual Sensory system
2 types of visual photoreceptors in the eye
Rods
Located on the periphery of the retina
See in dim light, no color information
Cones
Located in the fovea
See fine detail, clear vision, and color
Trichromatic Theory - individuals are able to see color b/c different wavelengths of light stimulate combinations of 3 color receptors - RED, GREEN, and BLUE
Opponent processing theory -