a vibratory disturbance that occurs in air or some other "medium"

used by waves moving through medium

Predict how changes in an auditory stimulus will affect its sound wave, and thus perception of that sound

frequency: cycles per second (Hz) - makes the waves look closer together - relates to pitch - inverse relationship between frequency and wavelength - ear drum reacts more to higher frequency

amplitude: the difference between the resting spot of the wave, and its peak (pressure) - makes waves taller - relates to loudness

 (instrument/timbre) = complexity: complex vs. pure tone - complex is often combining pure tones (additive synthesis) and fourier analysis is breaking it down

Interpret a graph depicting the audibility curve

threshold for humans: we cna hear above this threshold

we also have a threshold of feeling sound

NOTE: the equal loudness curves are not equal...just points along each individual line have the same percieved loudness

if its above the curve, its percieved loud

Diagram the auditory system from the outer ear to the auditory cortex.  Analyze each structure’s function in hearing

OUTER EAR

pinna (funnel sound and location) - external auditory canal (funnel vibrations to the ear drum, temperature control, amplifies important sound range) -

MIDDLE EAR

tympanic membrane/ear drum (vibrates to waves) - auditory ossicles: malleus, incus, stapes (vibrate in chain reaction to inner ear) - middle ear cavity - eustacian tube (connects the two cavities to equalize pressure and fluides) -

INNER EAR

oval window (recieves vibrations from stapes) - round window (comes out of cochlea from the scala tympani) - cochlea (holds organ of corti- basiliar membrane with hair cells moves against tectorial membrane & moves the perilymph fluids) - semicircular canals (the cochlea - scala vestibuli to scala tympani - inbetween is the scala media/cochlear partition)

TO THE CORTEX

cochlear nucleus - sonic mg (superior olivary nucleus, inferior colliculous, medial geniculate nucleus in thalamus) - auditory receiving area (A1) in temporal lobe - tonotopic map in cortex

they are necessary to amplify sound so it isn't dampened in the cochlear fluid

the same amount of force on a smaller area (like the stapes) creates increased pressure

curved like a snails shell....when rolled out:

perilympth fluid goes from oval window through the scala vestibuli around the helicotrema and the scala tympani and out the round window...

this causes the organ of corti to move : the bottom (basiliar membrane- with hairs) starts moving up and down while the top (tectoral membrane) starts moving back and forth, the tec. memb. starts pushing the cilia causing neurotransmitters to be released, and a signal is sent to the brain (depolarizing)

percieves loudness based on the amplitude, and how many cilia are bent

percieves pitch based on the envelope in the basiliar membrane (the max. peak of the wave at each part of the membrane) - high frequency is near base

ringing of the ears, ususally caused by loud sounds but also can be caused by drugs and ear infections or food allergies

caused by excessive build up of fluid in the inner ear

-hearing loss (can be permanent)

-tinnitus

-vertigo

normal: 25 +

mild: 24-45

moderate: 45-65

severe: 65-85

profound 85-130

benefits: has the capability of greatly improving speech, bypasses the outer and middle ear and goes straight through the cortex

pitfalls: very invasive surgery, can often take a patient a while to adjust to sound, most beneficial implanted early, has been shown to interrupt the "deaf community"

binaural: ITD, ILD

monaural: HRTF

auditory scene analysis: auditory grouping

binaural localization cue

subtract time to get to each ear

(works best for low frequencies)

appears louder in the closer ear (acoustic shadow)

works best for higher frequencies

monaural localization cue

the difference between sound from source and sound that actually enters the ear (changed by pinna)

• Protection
• Warmth
• Body temperature regulatio
• Vitamin D synthesis
• Blood resevoir
• Signals emotions

Merkel disks - between epidermis & dermis; SA1; fine details

Meisser corpuscle - in dermis just below epidermis; RA1; hand grip control

Ruffini organs - inside cyclindrical capsule; SA2; stretching of stimuli

Pacinian corpuscles - deep in skin; RA2; vibrations and fine textures

• slowly-adapting neuron: responds continuously to a maintained stimulus

• rapidly-adapting neuron: shows a quick drop in firing rate.

the minimum distance necessary to differentiate between two points touching you simultaneously

]Relation to skin sensitivity and

receptive fields

skin sensitivity - the smaller the distance of the two-point threshold, the more sensitive the area is

receptive fields - the more sensitive the area, the lower the two-point threshold...the receptive fields are closer together for more sensitive areas

nerve fibers (touch) - dorsal root - spinal cord - medial lemniscus (position) and spinothalmic (temperature and pain) pathways - thalamus (ventrolateral nucleus) - somatosensory cortex

points on the somatosesory cortex correspond to parts of the body (stimulation produces tingling)

homunculus - "little man"; the topographic map of the body in the somatosensory cortex (sensitive areas givene more area in the cortex); density of receptor cells

Exploratory procedures of Haptic touch

lateral motion

pressure

enclosure

contour following

1- attention to the pain

2- expectations about the pain

3- emotion (related to pleasantness)

4- meaning of pain (perhaps significant cultural pain doesnt feel as bad)

5- cultural differences and gender differences

Merkel Receptor:

location, adaptation, receptive field, perceptual correlate

l : border between epidermis and the dermis

a: slow and continuous

r: small

pc: fine detail and slow pressure

Meissner Corpuscle:

location, adaptation, receptive field, perceptual correlate

l: dermis (just below epidermis)

a: rapid/change

r: small

pc: flutter and hand grip control

Ruffini Cylinder

location, adaptation, receptive field, perceptual correlate

l: dermis

a: slow and continuous

r: large

pc: stretching

Pacinian Corpuscle

location, adaptation, receptive field, perceptual correlate

l: subcutaneous fat

a: rapid and change

r: large

pc: vibration and deep pressure

merkel receptor

meissner corpuscle

ruffini cylinder

pacinian corpuscle

  Explain how sound grouping can affect our ultimate perception of a sound.  Give specific examples

(5 ways)

basically when we group things we percieve it as one sound

1- location (2 cats meowing near each other)

2- proximity in time (2 cats meowing back and forth vs. one cat meowing quickly)

3- experience (previous knowledge- top down)

4- similarity of pitch and timbre (auditory stream segmentation (one stream divided into 2 when played quickly)

5-good continuation (shepard tone)

dermatome: specific part of the body which corresponds to a specific vertebra of the spinal chord

since the relationship exists between the dermatome and the vertebrae, the appearance of an infection on a specific dermatome yeilds to the vertebrae which is/are infected

L fibers, S fibers and central control effect t cells and the perception of pain

through SG+ and SG-

pain allows us to notice something is wrong with our body to fix it...not perceived, our body is in trouble

*spontaneous combustion*