Lecture 5: Perception Mechanisms Flashcards
1
Q
receive stimuli outside of our bodies
A
exteroceptive sensory systems
2
Q
Process of detecting the presence of stimuli
A
sensation
3
Q
Higher-order process of integrating, recognizing, and interpreting patterns of sensations
A
perception
4
Q
types of sensory areas of cortex
A
- primary sensory cortex
- secondary sensory cortex
- association cortex
5
Q
Areas that receive most of their input from the (1) primary sensory cortex or (2) other areas of secondary sensory cortex (in same system)
A
secondary sensory cortex
6
Q
Area that receives most of its input directly from the the thalamic relay nuclei
A
primary sensory cortex
7
Q
Any area that receives its input from more than one sensory system
A
association cortex
8
Q
most input in the association cortex comes via areas of __________
A
secondary sensory cortex
9
Q
Characterizes the interactions among the three types of sensory cortex and among other sensory structures
A
three major principles
10
Q
three major principles
A
- hierarchical organization
- functional segregation
- parallel processing
11
Q
“Sensory structures are organized based on the specificity and complexity of their function”
A
hierarchical organization
12
Q
“Each of the 3 cortex levels in a sensory system contain functionally distinct areas that specialize in different kinds of analysis”
A
functional segregation
13
Q
“information flows through the components over multiple pathways”
A
parallel system
14
Q
“simultaneous analysis of a signal in different ways by multiple parallel pathways of a neural network”
A
parallel processing
15
Q
Vibrations of air molecules (that stimulate the auditory system)
A
sounds
16
Q
human hearing capacity
A
20 - 20,000 hertz
17
Q
amplitude =
A
loudness
18
Q
frequency =
A
pitch
19
Q
complexity =
A
timbre
20
Q
A sound of one single frequency
A
pure tone
21
Q
pure tone exists only in
A
- laboratories
- sound recording studios
22
Q
related to fundamental frequency
A
pitch
23
Q
Mathematical procedure for breaking down complex waves into their component sine waves
A
fourier analysis
24
Q
Transmit sound vibrations from the external ear to the middle ear (particularly the ossicles)
A
tympanic membrane (eardrum)
25
3 small bones; Connected to each other and send the sound vibrations (which they amplify) to the inner ear (particularly the cochlea)
ossicles
26
3 small bones
- malleus
- incus
- stapes
27
the hammer
malleus
28
the stirrup
stapes
29
the anvil
incus
30
junction point between the middle ear and the inner ear
oval window
31
long, coiled tube with an internal structure (Organ of Corti) running almost to its tip
cochlea
32
cochlea is filled with ____ that ripples due to the vibrations
fluid
33
‘different hair cells respond to different frequencies of sound’
tonotopic
34
bundles of stereocilia move along the waves created by the rippling (due to vibration)
organ of corti
35
organ of corti convert wave movements into ____ signals which will travel along the auditory nerve
electrical signals
36
elastic membrane in cochlear wall
round window
37
current network of auditory pathways
axons of auditory nerves - medial geniculate nuclei - primary auditory complex
38
signals are transmitted to both ____ and _____
- ipsilateral
- contralateral
39
inherently complex in auditory system
subcortical pathways
40
Receives the majority of its input from medial geniculate nucleus
primary auditory complex
41
primary auditory complex is located in the ______
temporal lobe
42
areas of auditory cortex
- 13 separate areas
- core region
- belt
- parabelt areas
43
band of areas of secondary auditory cortex
belt
44
areas of secondary auditory cortex outside the belt
parabelt areas
45
collection of 3 adjacent areas in primary auditory cortex
core region
46
principles of organization
- organized in functional columns
- tonotopic
- periodotopy
47
vertically, auditory neurons tend to respond optimally to sounds in the same frequency range
organized in functional columns
48
organized acc. to temporal components of sound
periodotopy
49
periodotopy refers to the changes in ____ of sounds in our environment over a period of time
intensity
50
2 main cortical streams of auditory analysis
- anterior auditory pathway
- posterior auditory pathway
51
ultimately conducted to the prefrontal cortex and posterior parietal cortex
auditory signals
52
More involved in identifying sounds (what)
anterior auditory pathway
53
More involved in locating sounds (where)
posterior auditory pathway
54
have traditionally been assumed to interact in the association cortex
sensory system
55
areas of cortex where SS interactions (associations) take place
association cortex
56
Widely used to investigate SS interactions
functional brain imaging
57
effects of damage to the auditory system
- auditory cortex damage
- deafness
58
Major permanent loss of ability to process structural aspects of sounds
auditory cortex damage
59
- One of most prevalent human disabilities
- Can lead to feelings of social isolation
deafness
60
______ is rare (only 1%)
total deafness
61
2 common classes of deafness
- conductive deafness
- nerve deafness
62
damage to ossicles
conductive deafness
63
Damage to cochlea or auditory nerve
nerve deafness
64
major cause of nerve deafness
loss of hair cell receptors
65
Ringing of the ears
tinnitus
66
Advanced medical devices designed to provide a sense of sound to individuals with nerve deafness.
cochlear implants
67
sensations from the body
somatosensation
68
3 systems of the somatosensory system
- exteroceptive system
- proprioceptive system
- interoceptive system
69
Monitors conditions inside the body e.g. temperature, blood pressure.
interoceptive system
70
Has exteroceptors that sense external stimuli
exteroceptive system
71
Monitors information on the position of the body that comes from receptors in the muscles, joints, and organs of balance (vestibular system)
proprioceptive system
72
mechanical stimuli
pressure
73
thermal stimuli
temperature
74
nociceptive stimuli
pain
75
cutaneous receptors
- free nerve endings
- pacinian corpuscles
- merkel's disks
- ruffini endings
76
Neuron endings with no specialized structures
free nerve endings
77
free nerve endings are sensitive to ____ and _____
- temperature changes
- pain
78
Largest and deepest; onion shaped
pacinian corpuscles
79
Responds to skin indentation (from pressure)
merkel's disks
80
Respond to skin stretching and joint activity
ruffini endings
81
Continuous change in stimulation that enables more awareness towards particular object
stereognosis
82
stereognosis is identifying objects by ____
touch
83
2 major somatosensory pathways
- dorsal-column medial-lemniscus system
- anterolateral system
84
Tends to carry information about touch and proprioception
dorsal-column medial-lemniscus system
85
Tends to carry information about pain and temp
anterolateral system
86
somatotopic – organized according to a map of the body surface
primary somatosensory cortex
87
"little man"
homonculus
88
refers to the somatotopic map
somatosensory homunculus
89
input in primary somatosensory cortex is largely ______
contralateral
90
- Receives most of its input from SI
- Susbtantial input from both sides of the body
secondary somatosensory cortex
91
somatosensory agnosias
- astereognosia
- asomatognosia
92
Inability to recognize objects (shape and size) by touch
astereognosia
93
Inability to recognize parts of one’s own body or the loss of awareness of part of the body
asomatognosia
94
tendency not to respond to stimuli that are contralateral to a right-hemisphere injury
contralateral neglect
95
perception of pain
- pain is adaptive
- pain has no clear cortical representation
- pain is modulated by cognition and emotion
96
Severe chronic pain in the absence of a recognizable pain stimulus
neuropathic pain
97
neuropathic pain is caused by _____
abnormal activity in the CNS
98
primary function of chemical senses
to monitor the chemical content of the environment
99
response of the olfactory system to airborne chemicals that are drawn by inhalation over receptors in the nasal passages
smell
100
response of the gustatory system to chemicals in solution in the oral cavity
taste
101
2 adaptive roles of the chemical senses
- evaluation of potential foods
- regulate social interactions
102
chemicals that influence the physiology and behavior of members of the same species (conspecifics)
pheromones
103
an integrated sensory impression produced when molecules of food excite both smell and taste receptors
flavor
104
sensation of smell
olfaction
105
located in the upper part of the nose, embedded in a layer of mucus-covered tissue
olfactory receptor cells
106
mucus-covered tissue
olfactory mucosa
107
discrete clusters of neurons that lie near the surface of the olfactory bulbs
olfactory glomeruli
108
- Primary olfactory cortex
- Area of medial temporal cortex adjacent to the amygdala
piriform cortex
109
2 major pathways that leave the amygdala
- limbic pathway
- thalamic-orbitofrontal pathway
110
Thought to mediate the conscious perception of odors
thalamic-orbitofrontal pathway
111
Thought to mediate emotional response to odors
limbic pathway
112
used to refer to the still poorly understood topographic organization of the olfactory bulbs
chemotopic
113
sensation of taste
gustation
114
Muscular organ in the mouth; Essential for performing various functions related to speech, taste, chewing, swallowing, and maintaining oral health
tongue
115
Small, raised structures found on the surface of the tongue that give it its rough texture (in purple); Houses the taste buds (in orange)
papillae
116
can detect different tastes no matter their location
taste buds
117
taste buds contain ___ to ___ clusters of taste receptor cells
50 to 100
118
Specialized cells surrounded by nerve endings
taste receptors
119
taste receptors are found on the ______ and throughout the ______
- tongue
- gastrointestinal tract
120
how long does taste receptors survive before being replaced by new cells?
few weeks
121
3 main types of taste bud cells
- detects bitter, sweet, and umami
- detects sour
- detects salty
122
metabotropic receptors
- sweet
- umami
- bitter
123
ionotropic receptors
- salty
- sour
124
2 m receptors
sweet
125
about 25 m receptors
bitter
126
1 m receptors
umami
127
transduced by 3 ionotropic receptors
salty
128
mediated by 2 ionotropic receptors
sour
129
gustatory cortex includes
- primary gustatory cortex
- secondary gustatory cortex
130
Chemotopically organized
primary gustatory cortex
131
Responsible for processing and integrating more complex aspects of taste
secondary gustatory cortex
132
inability to smell
anosmia
133
Most common neurological cause: a blow to the head that shears the olfactory nerves where they pass through the cribiform plate
anosmia
134
Inability to taste
ageusia
135
limited to the anterior two-thirds of the tongue on one side
partial ageusia
136
The outcome of perception
percept
137
Prior Experiences affecting Perception
- Knowledge of how mundane things work (environmental learning)
- Knowledge of identity of objects
- Knowledge about temporal order of sensory events
138
consumes a large proportion of energy used by our brains
perceptual decision making
139
Mediation towards perceptual decision making is currently associated with the dorsolateral prefrontal cortex and the posterior parietal cortex
neural mechanisms
140
The product of perception when there is an absence of sensory input.
phantom percepts
141
presence of a missing limb is still perceived long after it has been lost to injury/amputation
phantom limbs
142
Individuals experience rich and complex hallucinations
charles bennet syndrome
143
suggested potential location
claustrum
144
a claustrum is a structure that is made up of a fine sheet of ____ located just underneath the ___ towards the middle of the brain
- neurons
- cortex
145
Process where we consciously perceive only a small subset of the the many stimuli available at any one time and largely ignore the rest.
selective attention
146
Characteristics of Selective Attention
- It improves the perception of the stimuli in focus
- It interferes with the perception of the stimuli not in focus
147
2 ways of focusing attention
- internal cognitive processes
- external events
148
internal cognitive processes are also called
endogenous attention
149
external events are also called
exogenous attention
150
2 types of attention (based on eye movement)
- covert attention
- overt attention
151
mediated by top-down (from higher to lower levels) neural mechanisms
internal cognitive processes
152
mediated by bottom-up (from lower to higher levels) neural mechanisms
external events
153
A shift of visual attention without any corresponding eye movement
covert attention
154
A change in visual attention that involves a shift in gaze
overt attention
155
phenomenon related to attention
- cocktail-party phenomenon
- change blindness phenomenon
156
Even when you are focusing so intently on one conversation that you are totally unaware of the content of other conversations going on around you, the mention of your name in one of the other conversations will immediately gain access to your consciousness.
cocktail-party phenomenon
157
the image is composed of two images that alternate with a delay of less than 0.1 second between them
change blindness phenomenon
158
play major roles in directing top-down attention
- prefrontal cortex
- posterior parietal cortex
159
selective attention may operate in the principle of a _____
push-pull mechanism
160
Currently identified as important to attentional gaze
frontal eye field
161
disorder of attention
simultanagnosia
162
Difficulty in attending visually to more than one object at a time
visual-simultanagnosia
