exam 4 Flashcards
1
Q
sensation
A
acquisition of information
2
Q
perception
A
processing and interpretation of information
3
Q
receptor cells
A
specialized neuron that responds to a particular form of energy
4
Q
what do receptor cells do
A
convert energy into a neural response
5
Q
what form must energy be to be percieved by a receptor cell
A
the energy form for which the receptor is specialized
6
Q
law of specific nerve energies
A
the nature of perception is defined by the pathway over which the sensory information is carried
(our experiences are a product of nerve ending stimulation)
7
Q
Who proposed the Law of Specific Nerve Energies, and when
A
Johannes Peter Muller in 1835
8
Q
Adequate stimulus for hearing
A
vibration in a conducting medium
air vibrates from the vibration of the sound’s source
9
Q
Why is sound complicated
A
Sounds vary in intensity and frequency and can change rapidly
10
Q
How does hearing perception deal with the complication of sound
A
The parts of the ear and the brain work together to analyze these complex sounds
11
Q
Frequency
A
Number of cycles or waves of alternating compression and decompression of the vibrating medium that occur in a second
12
Q
How do we measure frequency
A
Hertz (Hz)
13
Q
What is pitch
A
Our experience of the frequency of sound
14
Q
Amplitude
A
Height of sound waves which dictate intensity or physical energy of the sound
15
Q
What is loudness/volume
A
Our experience of sound energy
16
Q
What are pure tones
A
Sound comprosed of one frequency
17
Q
What are complex tones
A
sound comprised of a mixture of frequencies
18
Q
What do complex tones sound like
A
A random combination of frequencies would sould like mere noise, but complex sound can also be musical
19
Q
Do we hear pure or complex tones more often
A
We rarely hear pure tones, complex tones made of many frequencies are much more common
20
Q
What did George Fourier realize
A
Complex sound is a product of two or more sine waves
21
Q
What is a Fourier Analysis
A
The breaking of complex sounds into component frequencies
22
Q
Georg Ohm
A
Proposed the ear does a Fourier Analysis of complex sounds and sends information about each compoent of the frequencies to the cortex
23
Q
What part of the ear conducts the Fourier Analysis and responds to a sounds component frequencies?
A
basilar membrane
24
Q
Waveforms
A
A combination of all of the waves produced by a sound
25
What pieces comprise the outer ear?
Pinna and Auditory Canal
26
Pinna
Flap of skin and cartilage protruding from either side of the head that captures and amplifies sound into the auditory canal
27
Auditory canal
Funnels sound toward the eardrum
28
What is the outer ear designed to do
Select for sounds from the front
29
What pieces comprise the middle ear
Tympanic membrane, ossicles, and estucian tube
30
Tympanic membrane
AKA eardrum, a very thin membrane stretched across the end of the auditory canal
vibration of the eardrum transmits sound energy to the ossicles
31
Ossicles
very tiny bones that operate in a lever-like fashion to transfer vibration from the tympanic membrane into the cochlea
32
33
What is the function of the ossicles
provide addtional amplification by concentrating the energy collected fromt he larger tympanic membrane to the much smaller base of the stirrup, which rests on the cochlea
34
What are the bones in the ossicles
Maleus (Hammer), Incus (Anvil), Stapes (stirrup)
35
Eustachian Tube
Connects your middle ear to the back of your mouth to equalize pressure in your moth to equalize pressure in your ear to the outside world
36
What pieces comprise the inner ear
Cochlea, semicircular canals, auditory nerve, organ of corti
37
Cochlea
Contains sound analyzing structures, subdivided into three fluid-filled canals
38
What are the canals in the cochlea
cochlear, vestibular, tympanic
39
Cochlear canal
passes vibration to the organ of corti which rests on the basilar membrane
40
Vestibular canal
Point of entry of sounds
41
Tympanic canal
Allows pressure waves to travel in cochlear fluid
42
Semicurcular Canals
Filled with fluid that help with balance
43
Auditory Nerve
sends the sound signal to the brain
44
Organ of corti
contains the tectorial membrane and hair cells
45
Hair cells
specialized receptors for sound waves
46
Process of sensation/perception in hair cells
1. Vibration bends hair cells, opening Ca+ and K+ channels
2. K+ induces depolarization
3. When the hair cells move back in the opposite direction, K+ channels close
47
Types of hair cells
Single row of 3,500 hair cells, which recieve 90%-95% of all auditory information
Three rows of 12,000 outer hair cells, which increase the cochlea's sensitivity
48
What pieces comprise the auditory pathway into the auditory cortex
Auditory nerve, inferior colliculi, medial geniculate nucleus, primary auditory cortex
49
Auditory nerve
8th cranial nerve
50
Inferior colliculi
Where the sounds from both ears converge
51
Medial geniculate nucleus
Processes information from opposite ear
52
Where is the primary auditory cortex located
Temporal lobe
53
Auditory cortex
uses tonotropic organization, in which cells are tightly tuned to specific frequencies
54
Tonotropic organization causes what in the auditory cortex
the auditory cortex forms a map of the basilar membrane so that each successive area responds to progressively higher frequencies
55
Frequency theory
Auditory mechanism transmits the actual frequency of sound into the auditory cortex
56
Telephone theory
early version of frequency theory, neurons in the auditory nerve fire at the same frequency as the rate of the sound source
57
Research on frequency/telephone theory
Attatched electrode to the auditory nerve of a cat and stimulated its ear with various sounds
auditory nerve was firing at the same rate as the stimulus (does account for high frequencies, as the refractory period of neurons is too long)
58
Place theory
the frequency of sound is identified according to the location of maximal vibration on the basilar membrane and, therefore, which neurons are firing most
59
Cochlear / Basilar Membrane Map
High frequencies cause the base end to vibrate most, and low frequencies cause the apex to vibrate most
60
Why is place theory alone inadequate to describe how we interpret frequencies
Basilar membrane vibrates equally throughout low range of hearing
frequency specific neirons have not been found below 200 Hz
We can hear frequencies ranging from 20-20,000 Hz and can distinguish differences of only 2-3 Hz
61
Frequency-Place Theory
researcher-accepted combination of the two theories
Frequency encoding at low frequencies (<500 Hz)
Place encoding for everything else
62
What are the two streams of the auditory cortex
Dorsal stream and ventral stream
63
Dorsal Stream
Parietal lobe to Frontal lobe
Interprets where the sound is
Travels from the auditory cortex to the parietal lobe or frontal lobe
64
What is the function of the parietal lobe in the dorsal stream
Spatial location of sounds
65
What is the function of the frontal lobe in the dorsal stream
Planning and directing movements
66
What is the overall function of the dorsal stream
Combine information with other senses to locate a sound in relation to the visual scene
67
Ventral stream
temporal lobe to frontal lobe
identifies what the sound is
68
What is the function of the temporal to frontal lobe pathway in the ventral stream
Secondary auditory areas are involved in analyzing ocmplex sounds and understanding their meaning
69
What are the functions of the secondary auditory areas in the ventral stream
these areas are active when someone is trying to identify a sound
70
Cocktail party effect
we must sort out meaningful sounds embedded in a confusing background of sounds
71
Selective attention
brain enhances some sounds around us and suppresses others
ex: cocktail party effect
72
What happens as we identify a distinct sound
Relevent and irrelevant sounds are distunguished and separated
73
Where are sounds identified after separation
ventral area
74
where are voices identified
superior temporal area
75
where are environmental sounds identified
primarily in the posterior temporal areas, and to some extent, the frontal areas
(both dorsal and ventral pathways are used)
76
language
generation and understanding of written, spoken, and gestural communication
77
aphasia
impairment of language skills
78
where is language processed in the brain
more widely distributed than originally thought, some areas more implicated than others
79
Broca
stroke patient with frontal lobe damage
80
Broca's (expressive) aphasia
includes non-fluency, anomia, inarticulation, and agrammar
81
Non-fluency
good with yes and no (and sometimes explitves), but speech is halting
82
anomia
trouble finding the right words
83
inarticulate
misprononciation of words
84
agrammatic
uses content words (nouns and verbs) but has trouble with adjectives, conjunctions, and adverbs
85
Wernicke
Had posterior superior temporal gyrus damage (now called Wernicke's area)
86
Werenicke's (receptive) aphasia
trouble understanding spoken and written language, has trouble producing and understanding language, word salad
87
word salad
speech is fluent but meaningless
88
Wernicke-Geschwind Model of Language
proposed model of how Broca's and Wernicke's areas interact to produce langauge
89
Wernicke-Geschwind Model of Language pathway
1. verbal input arrives in the auditory cortex and travels to Wernicke's area for interpretation
2. written input arrives there via the visual cortex
3. If a verbal response is required, Wernicke's area sends output to Broca's area for articulation of response
4. Facial area of motor cortex produces the speech
90
Ancient Greek Belief about vision
Light beams from our eyes illuminate objects
91
16th century swiss belief about vision
Felix Platter proposed that eyes recieve light
92
How do we see
Light from an external source enters the eye, is refracted, and the image is sent to the back of the eye
93
What is the adequate stimulus for vision
visible light
94
Visible light
A part of the electromagnetic spectrum that includes a variety of energy forms
accounts for 1/70th of the range of the EMS
95
Wavelength
The distance the oscillating energy travels before it reverses direction
96
What is the wavelength range of visible light
380 nm to 750 nm
97
Sclera
Outer covering of the eye
Opaque except of the cornea
98
Cornea
transparent tissue in front of the eye
refracts light as it enters the eye
99
Aqueous humor
sits behind the corena
removes waste and supplies nutrients to the cornea and the lens
100
Iris
circular muscle that expands and contracts the pupil
101
Pupil
a hole in the iris that allows light into the eye
light must pass through to get to the lens
102
Lens
transparent, recieves the light that passes through the pupil
103
ciliary muscles
stretch the lens flatter to focus the image of a distant object on the retina
relaxes the lens to focus the image of a nearer object
104
Vitreous humor
jelly like substance that makes up 80% of the eyes volume
refracts light after it passes through the lens
105
where does light go when it enters the eye
some of the light will make it to the retina
the rest gets absorbed/scattered in other parts of the eye
106
How do images appear in the eye
mechanically, we see everything upside down
refraction through the lens flips the image, so when the image hits your retina it is completely inverted
107
retina
detects light and tells the brain about aspects of light related to objects in the world
where seeing begins
108
Light Sensitive Receptors
contain photopigments that break down in the presence of light
we have two types of receptors, so we have duplex retinas
109
Photoreceptors at rest
Photoreceptors are more active in darkness
Na+ and Ca+ channels open
Glutamate is released, inhibiting bipolar cells
110
What happens when light strikes a photopigment
Na+ and Ca+ channels close
Glutamate release is reduced
Bipolar cells increase their firing rate, which increases firing in the ganglion cells
Signal travels from optic nerve into the brain
111
what are the two types of photoreceptors
rods and cones
112
Rods
contain rhodopsin
function well in dim light and poorly in bright light (scotopic vision)
distinguish light levels (no colors)
located in the periphery of the retina
113
Cones
Contain iodopsin
Function well in bright daylight and poorly in dim light (photopic vision)
Allows for color vision
Located in the fovea
114
Types of cones
S-cones: Blue
M-cones: Green
L-cones: Red
115
Receptive fields
Circilar regions on the retina in which certain light stimuli hitting a collection of cones or rods can influence a ganglion cell's firing rate
can be exititory and inhibitory
116
What role do rods and cones play in receptive fields
Rods and cones create their own receptive fields on ganglion cells
117
Receptive field of cones
small
only one cone per ganglion cell
118
Visual acuity
the ability to distinguish details
119
where is visual acuity the greatest
the fovea
decrease toward the periphery
120
receptive field of rods
large
many rods share each ganglion cell
this results in light sensitivity
121
Where are cones most present
in the periphery
absent in the fovea
122
where in the brain do receptive fields correspond
lateral geniculate nucleus of the thalamus
123
lateral geniculate nucleus
pre-processes information and then it goes into the primary visual cortex
