Module 20 (Hearing/Consciousness) Flashcards
Cochlea
-a coiled, bony, fluid-filled tube in the inner ear
-sound waves traveling through cochlear fluid trigger nerve impulses
Changes in air pressure
-Frequency (changes pitch) depends on cycles per second (hertz)
-Amplitude (changes loudness) depends on high/low (decibels)
Basilar membrane
-a mechanical structure in the inner ear that separates sound into different frequencies
-contains small hair cells that bend, causing neurons to fire action potentials
Hearing loss
-ear buds (close to ear) cause low-frequency hearing loss (common in young adults)
-maximum is about 100-110 decibels
-at 60 decibels, safe
Cochlear implants
-devices for people with complete deafness
-electrodes implanted in cochlear near auditory nerve, directly stimulates it
Consciousness
-what we are aware of at any given time
-what we sense/perceive
-affected by attention, altered states (drugs), wakefulness
Stroop effect
-show 3 different column (rectangles, words, and colors)
-reading= automatic
-color naming= controlled
Circadian rhythm
-24-hour body clock
-alertness, body temp, and hormone release function on circadian rhythm
-follows 25-hour clock
Stages of sleep
-awake
-drowsy
-stage 1 (theta waves prominent)
-stage 2 (sleep spindles)
-slow wave sleep (stage 3 and 4, delta waves)
-REM-sleep (low-voltage, high frequency, similar to awake)
REM (rapid eye movement) sleep
-one of most important brain stages
-brain activity closest to waking state
-muscles are most relaxed
-least likely to sleep walk (most likely around stage 1)
-deprivation results in REM rebound
-awakening during REM results in 90% reporting dreaming
Stages of sleep throughout night
-4-5 cycles per night (each cycle ~90 minutes)
-begins in stage 1, stage 4 after around 30 min.
-easiest to wake/more alert in earlier cycles
-least alert in REM
-duration of REM increases throughout night, while stage 4 decreases
How much sleep do people need?
-most need 7-9
-small percent need less/more
-as you get older, total time asleep decreases, total time in REM remains steady