sensory system Flashcards
(138 cards)
1
Q
receptors
A
receive stimulus
2
Q
what type of pathways are sensory pathways and what do they transmit
A
nerve axons and afferent pathways
transmit signals
3
Q
central nervous system
A
interpret or integrate sensory inputs
4
Q
what type of pathways do motor systesm have and what do they produce
A
efferent pathways
produce response
5
Q
two types of receptors
A
nerve cell
specialized epithelial cell
6
Q
activation of receptors are stimulus ___ and they transform an _____ stimulus to an _____ signal
A
stimulus specific
transform an external stimulus to an electrical signal
7
Q
what do sensory pathways describe
A
describe the type and location of the sensory stimulus
8
Q
the sensory pathway type is dependent on what?
A
dependent on what type of receptor is activated
9
Q
each receptor has a specific location of sensory pathway where
A
on the sensory map in the brain
10
Q
what is the dorsal root ganglion
A
collection of cell bodies of the afferent sensory fibers
11
Q
what is the dorsal root ganglion associated with
A
posterior or dorsal root of the spinal nerve
12
Q
the dorsal roots contain..
A
sensory fibers from the skin , subcutaneous and deep tissues and viscera
13
Q
what afferent fibers are composed of myelinated?
A
cutaneous, joint and visceral
14
Q
define perception of the CNS
A
the integration of sensory impressions into psychologically meaningful information
15
Q
sensory maps
A
the location of sensory receptors in the brain
16
Q
what does the sensory homunculus show
A
shows the somatic sensory projections from the body surface
17
Q
sensory integration
A
the ability to use sensory information efficiently
ex. drawing , writing
18
Q
what systems are involved in stable standing balance
A
somatosensory system
vision
vestibular system
19
Q
what do receptors define?
receptors transform ____ stimulus into ____ signals
A
defines type, location, and intensity of stimulus
transforms external stimulus into electrical signal
20
Q
the sensory pathways transmits _____ ____ to areas of the ___ that corresponds with ____ _____
A
transmits electrical signal to area of brain that corresponds with receptor location
21
Q
the central nervouse system ____ and ____ what type of signals ?
it communicated with ____ system to produce what
A
interprets and integrates sensory signals
motor system to produce goal directed movement
22
Q
what are the different types of somatosensory system receptors
A
mechanorecptors
thermoreceptors
nociceptors
23
Q
mechanoreceptors
A
touch , pressure, vibratior proprioception
24
Q
thermoreceptors
A
heat and cold
25
nociceptors
pain
26
somatosensory system provides
sensory information about the body
27
where does cutaneous sensation of touch come from
comes from outside of the environment
28
proprioceptive sensation from..
ligaments , muscles, joints, and tendons
29
interception
perception of sensation from inside the body
30
proprioception
perception of ones body in space
31
function of somatosensory system
transmits informations about the sense of touch, pain, temperatures and body position from sensory receptors to the cns to regulate behavior
32
order of sensory system development
touch > vestibular > smell > hearing > vision > taste > proprioception
33
what system is the first to function in utero
touch - allows for communication and attachment
34
when are proprioceptive receptors well developed
by mid fetal life
35
gestation - 7 weeks
fetus responds to touch around mouth
36
gestation- 12 weeks
muscle spindles formed
37
gestation- 16 weeks
golgi tendon organs formed
38
gestation- 17 weeks
cutaneous sensation spread to entire body
39
are all sensory systems ready to function at birth?
yes
40
is the peripheral nervous system unmyelinated or myelinated?
myelinated
41
during maturation (infancy and childhood) touch is
used by infant to locate food
ex; roofing reflex
42
touch is a crucial role in
parent infant attachment, sociability and cognitive development
43
12-16 months ( somatosensory system)
specific touch localization
44
5 years (ss)
identify objects by touch
45
7 years (SS)
two point discrimination
46
how is proprioception used during infancy and childhood
execuation of purposeful movements such as imitation, reaching, and locomotion
ability to achieve and maintain upright postures
47
when does muscle spindles mature
as early as 3 years old
48
when does proprioceptive acuity fro movements improve
between age 5-12
49
when is the sensory system the keenest?
during late adolescence into early adulthood
50
what does maturation and integration of somatosensory system do
guide motor abilities and skill refinement
51
when does sensory function begin to decline
adulthood
52
sensory receptor functions decline in
middle age
53
peripheral and central changes
small and gradual
54
when does reaction time peak?
mid 20’s
55
how much does reaction time decrease during middle adulthood
20%
56
why does skin becomes dry and less elastic during adulthood
compromised precision of cutaneous receptors
57
what are the gradual decline in sensory functioning with aging
decrease in number of sensory neurons
decline in functioning of sensory neurons
struggle and physiological changes within the cns
58
what leads to peripheral neuropathy
a loss uo to 30% of sensory fibers innervation peripheral receptors
59
what is the impact on proprioceptive system with aging
atrophy of muscle spindles. joint receptors and GTO’s
arthritic changes affect the ability of joint receptors to detect joint motion
60
is redundancy of sensory informaition decreased by age related changes?
yes
61
what is a dominant sensory modality in humans
visual system
62
vision provides individuals information about
the external world
identification of external objects
where the body is in space , the relationship of ones body parts, and the motion of ones body
63
what is vision vital in?
control of posture, locomotion, balance , and hand function
64
peripheral anatomy
structures and receptors in the eyeball
6 extracular muscles
65
central anatomy
optic nerve
optic chias
optic tract
optica radiations
occipital cortex
66
what is the optic nerve
carries nerve impuluses
67
what is important elements leading to visual function
head position and head control
68
4 types of eye movements are controlled by the
6 extracular muscles
69
eye movements - saccades
quick , simultaneous movement of both eyes in the same direction
70
eye movements - slow pursuit or tracking
slow, smooth eye movements
allow the eyes to closely follow moving objects
71
eye movements, reflex eye movement that stabilizes images on retina produces eye movement in opposite direction to head movement -
vestibule-ocular reflex
72
eye movement- vergence
simultaneous movement of both eyes in opposite direction
73
convergence
eyes rotate towards each other
74
divergence
eyes rotate away from each other
75
visual system- prenatal
where is the visual ssytem dervied from
derived from thalamus in diencephalon
76
where does most peripheral structures develops
into the eyeballs
77
in what week does the eye forms?
4th week
78
when does myelination begin in the visual system?
13th week
79
once formed , the visual system extends to
occipital poles and forms horizontal axis of brain
80
when are the neurons in the occipital cortex organized into their adult layers?
during 2nd half of gestation
81
what happens during the 6th month of gestation for the visual system
reflexive eye blinking
82
when does complete maturation of sensory pathways occur?
after birth
83
what is the visual acuity in new borns
20/800
84
what colors do newborns see in
black and white
85
what is the best distance for fixation for a new born
7-9 inches away from eyes
86
do new borns have a pattern preference when born?
yes especially for a human face
87
visual system- 2months
see 2 colors (yellow and red)
track vertically , horizontally, and in circular path
88
visual system- 3 months
preference for a colored object
perception of form
89
by 4 months infants have what type of vision
full color vision
90
when does binocular vision mature
3-5 months
91
when d oes adult like binocular vision occur?
by 2 years old
92
visual system -12 months
adult levels of visual acuity achieved (20/20)
93
what does postural control promote
visual interest
94
what does head control facilitate?
visual fixation on objects
95
when is the greatest requirement for visual feedback
during first 3 months after child begins sitting and standing
96
when are colder highly dependent on visual feedback for upright postural control and balance
between 4-6 years
97
when does visual perception become increasingly more accurate?
preschool years
98
during adolescence your visual system..
matures and becomes more sophisticated
99
during adolescence (visual system)
eye hand coordination and perception action coupling become a thing (ex: baseball, pinball, and computer games)
100
at what age does perceptual judgments regarding size of objects
age 11
101
at what age does adult levels of depth perception achieved ?
12
102
during adulthood what are the changes in visual acuity?
increase in 20’s and 30’s and remains stable during 40’s and 50’s
103
what is the most rapid decline for changes in visual acuity?
between 60-80 years old
104
when doe cataracts being to form?
in individuals over 30
105
after the age of 40.. (visual system)
there is a decline in the ability to quickly adapt from light to dark environments
106
when does presbyopia begin?
age 45
107
what is presbyopia
degeneration of the eyes
108
is ther an increases visual threshold with older people? and what does that meam?
yes there is and it means more light is required to see; decreased ability to adapt from dark to light environment
109
what is the % of cataract formation of adults over 65?
60%
110
what is the % of muscular degeneration of adults over 75?
28%
111
in older adults their field of vision is ___ and they have a loss of ____ _____
the field of vision diminished > loss of depth perception
112
contrast sensitivity decrease between
65-75
113
what is the function of the vestibular system?
provides information regarding the position of the head in space
114
the vestibular system detects
sudden changes in the direction of movement of the head
115
the 2 rotations of the head
linear (otolith organs) and rotational (semicircular canals) accelerations
116
the vestibular system inputs intergrate ____ and ____ infromation to coordinate what?
visual and proprioceptive information to coordinate motor responses
117
Which system assists with eye stabilization and static and dynamic postural stability during standing and walking
vestibular system
118
during the prenatal stage the vestibular structures ..
being as a thickening of the ectoderm within the primitive ear in the 4th week of gestation
119
during 10 weeks of gestation what vestibular structures emerge?
semicircular canals , utricle, and saccule completely formed
120
what does the vestibular apparatus do when the fetus moves in utero
provides information about that movement happening
121
Is the vestibular system unmyelinated or myelinated at birth/
myelinated
122
the vestibular system in infancy and childhood leads to
development of trunk righting and equilibrium reactions
123
What contributes to the maturation of the vestibular system
rocking and spinning
124
during infancy and childhood the vestibular system develops the ability ..
to relate eye movements to head movements
125
when does normal vestibular ocular reflex present?
2 months of age
126
when does vestibular sensitivity peak
between 6 to 12 months of age
127
when does vestibular sensitivity decline
from ages 2.5 to puberty
128
During the ages 10 and 14 the vestibular system..
fully matures
129
what does full maturity of the vestibular system contrite be to?
healthy body scheme and gravitational security
130
what coordinate together to control balance
vision, vestibular and somatosensory systems
131
When is static balance gained?
9-12 years
132
when is dynamic balance gained?
12 years
133
For the vestibular system, when does age related changes occur?
being at 40’s
134
What happened during adulthood for the vestibular system /
decreased number of sensory cells and nerve fibers in the PNS
neural changes possible in the vestibular nerve
135
does the vestibular system show a decline in function with aging?
yes
136
what are the common issues for over 50 years? (VS)
dizziness and vertigo
137
fro adults over 70 there is a … (VS)
40% reduction in hair cells and 36% reduction in peripheral nerve fibers
138
there is a deterioration in central vestibular integrative functions which leads to
impaired balance
