Sensory Physio Flashcards
1
Q
Specialized cells for obtaining information about the environment
A
Sensory cells
2
Q
What pump promotes transmitter release
A
Ca2+
3
Q
Name all the cranial nerves and their function
A
Only one of the two athletes felt very good, victorious, and healthy
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abduscens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
Some say mary money but my brother says big brains matter more
Sensory
Sensory
Motor
Motor
Both
Motor
Both
Sensory
Both
Both
Motor
Motor
4
Q
Cranial nerve: functions in sense of smell
A
Olfactory
5
Q
Cranial nerve : functions in vision
A
Optic nerve
6
Q
Cranial nerve : functions in movement of eyeball and pupil constriction
A
Oculomotor nerve
7
Q
Cranial nerve : movement of the eyeball
A
Trochlear nerve
8
Q
Cranial nerve : functions in general sensation in face, scalp, corneas, and nasal and oral cavities and; chewing
A
Trigeminal nerve
9
Q
Cranial nerve :functions in movement of the eyeball
A
Abduscens nerve
10
Q
Cranial nerve :functions in taste, facial expression, and secretion of tears and saliva
A
Facial nerve
11
Q
Cranial nerve :functions in hearing and balance
A
Vestibulocochlear nerve
12
Q
Cranial nerve :functions in teste and sensation from the back of the tongue; swallowing and speech and; secretion of saliva
A
Glossopharyngeal nerve
13
Q
Cranial nerve :functions in taste and sensation from epiglottis and pharynx; swallowing and speech and;muscle contraction of thoracic and abdominal organs and secretion of digestive fluids
A
Vagus nerve
14
Q
Cranial nerve :functions in head and shoulder movement
A
Accessory nerve
15
Q
Cranial nerve :functions in movement of the tongue muscles
A
Hypoglossal nerve
16
Q
3 primary roles of sensors
A
- Proprioceptors = detect the animal’s position in space
- Interoreceptors = detect internal body signals
- Exteroreceptors = detect external signals such as light, chemicals, etc.
17
Q
Our perception of the world is incomplete because
A
- Detect only a limited number of energy forms
- Perceive sounds, color, shapes, textures, smells, taste, deformations, and temperature
- Di not perceive magnetic forces, electrical forces, polarized light waves, or ultraviolet light waves
- Information we receive is filtered or modified (at the receptor, brainstem, or cortex)
18
Q
Term in receptor physiology : change detectable by the body
A
Stimulus
19
Q
Term in receptor physiology :form of energy that stimuli take
A
Modality
20
Q
Term in receptor physiology :structure that respond to a particular modality
A
Receptor
21
Q
Term in receptor physiology :conversion from one form of energy to another
A
Transduction
22
Q
Classes of sensory receptors
A
Mechanoreceptors
=in skin, muscle and tendons, and blood vessels
Thermoreceptors
= in skin
Photoreceptors
=in retina
Chemoreceptors
=in tongue and nose
Nociceptors (stimuli causing tissue damage)
=throughout the body
23
Q
Modality with the lowest energy that would activate the receptor
A
Adequate stimulus
24
Q
Johannes Muller - receptors would only respond to certain stimulus and not to others
A
Doctrine of specific nerve energies
25
Sensation perceived depends on receptor activated, not stimulus
26
Types of sensory structural design
1. Primary sensors
- Dendritic endings of sensory neurons
- simulation directly evokes APs in neuron
2. Secondary sensors
- specialized sensory cell
- stimulation of sensor induced release of neurotransmitter to sensory neuron
27
A receptor may either be:
A modified nerve ending - generator potential
Another cell closely associated with the sensory neuron - receptor potential
28
Sensory adaptation:
• exhibit little adaptation
• maintain constant firing rate as long as stimulus is applied
• do not adapt at all, or adapt slowly
• E.g. muscle stretch receptors,
pressure, slow pain
Tonic receptors
29
Sensory adaptation:
• exhibit sensory adaptation
• firing rate of receptor (# AP’s)
decreases with constant stimulus
• adapt rapidly
• exhibit “on” “off” responses
• E.g. Touch to the skin (Pacinian
corpuscles)
Phasic receptors
30
4 steps to Sensation
1. Simulation
2. Transduction
3. Conduction
4. Perception
31
A step to sensation:
•application of stimulus
•Must be strong enough to
induce AP in sensory neuron
•Sensors most sensitive to one
particular stimulus modality
(adequate stimulus)
Stimulation
32
A step to sensation :
•induction of an action potential
•Stimulation of sensor induces graded potentials in
sensors
•generator potentials, or receptor potentials
•If strong enough depolarization, AP results
•↑ stimulus strength above threshold
→ ↑ AP firing rate
Transduction
33
2 kinda of sensory transduction mechanisms
1. Ionotropic transduction
2. Metabotropic transduction
34
A kind of sensory transduction where a stimulus triggers channels to open by direct action
Ionotropic transduction
35
A kind of sensory transduction where a stimulus triggers channels to open indirectly via a second messenger
Metabotropic transduction
36
A step to sensation:
• relay of information through a sensory pathway to specific
region of CNS
Conduction
37
There are usually how many neurons in sensory pathway?
3
• 1st order neuron
from stimulation point to CNS
• 2nd order neuron
e.g., from entry into CNS to thalamus
• 3rd order neuron
e.g., from thalamus to perception site
38
A step to sensation:
• Detection of environmental change by CNS
• Evaluation of nature of change and magnitude
Perception
39
Is an area of the body that,
when stimulated, changes
the firing rate of a sensory
neuron
Receptive field
40
If the firing rate of the
sensory neuron is increased,
the receptive field is
________
excitatory
41
If the firing rate of the
sensory neuron is decreased,
the receptive field is
__________
inhibitory
42
ability to discriminate
size, shape of an object in
the environment
Acuity
43
Higher receptor density,
Lower receptive field size,
Higher acuity
44
Two-Point Discrimination
Thresholds
refer to the minimum distance at which two separate points of stimulation can be perceived as distinct by the sensory system
45
______ homunculus concerns the signals transmitted through the frontal lobes
Motor homunculus
46
____ homunculus concerns the signals through the thalamus
Sensory homunculus
47
Brodmann's area 4
Motor homunculus
48
Brodmann's area 1.2 and 3
Sensory homunculus
49
✓sensors located over wide areas of the body
✓Information usually conducted to the spinal
cord first (then possibly the brain)
Somatesthetic senses
50
✓Changes detected only by specialized sense
organs in the head
✓Information conducted directly to the brain
Special senses
51
4 somatesthetic senses
1. Touch and pressure
2. Heat and cold
3. Limb movements
4. Pain
52
SOMATESTHETIC SENSES: SENSOR STRUCTURE
1. Free nerve endings
2. Expanded dendritic endings
3. Encapsulated endings
4. Bundled receptors
53
Dendrites wrapped by glial cells or connective tissue
Connective tissue enhances sensitivity or selectivity of the response
Encapsulated nerve endings
54
Meissner's corpuscle
Pacinian corpuscle
Ruffini's ending
Free nerve ending
Merkel's disk
Hair follicle receptor
55
Thermoreceptors
• Cold-sensing channels activated by _______
• Warm-sensing channels activated by ______
menthol
capsaicin (chili peppers)
56
Pain is associated with the detection and perception of ______ stimuli
(nociception)
noxious
57
The reception for
pain are free nerve
endings in the skin,
muscle, and viscera
58
Fast pain is carried by
group ___ fibers
III
59
Fast or slow pain? It has a rapid onset and offset , and is localized
Fast pain
60
Slow pain is carried by ____ fibers
C
61
Fast pain or slow pain? It is characterized as aching, burning, or throbbing that is poorly localized
Slow pain
62
Referred pain
Pain of visceral origin
Ex.
Dermatome rule
Heart attack could trigger jaw pain
63
Hyperalgesia
An increased sensitivity to feeling pain and an extreme response to pain
64
Allodynia
"pain due to a stimulus that does not normally provoke pain." An example would be a light feather touch (that should only produce sensation), causing pain.
65
2 possible destinations for sensory information upon entwined the spinal cord
1. Party of spinal reflex arc
2. Relayed up ascending to somatosensory cortex
66
5 special senses
1. Taste
2. Smell
3. Hearing
4. Vision
5. Equilibrium
67
Another term for taste
Gustation
Latin - gustare, to taste
68
•contain microvilli that project to the external surface
•When chemicals come into contact with these hairs,
buds release NT to sensory neurons → APs
Taste buds
69
Gustation
Signal travel to the parietal lobe (inferior post central gyrus)
70
Different tastes derived from
activation of different signaling
pathways within the cells
Salty (high [Na+])
Sour (high [H+])
Sweet (organic molecules)
Bitter (toxins)
Umami (glutamate)
71
In contrast to olfactory
receptor cells, taste
receptors are not neurons
They are specialized cells called gustatory cells or taste cells
72
Tongue part:
•Has fungiform papillae
•Detect salty and sweet sensations
•Is innervated by CN VII (chorda
tympani)
The anterior two-thirds of the
tongue
73
Tongue part:
•Has circumvallate and foliate papillae
•Detects sour and bitter sensation
•Is innervated by CN IX (glossopharyngeal)
The posterior one-third of the
tongue
74
3 types of papillae
Fungiform papillae
Foliate papillae
Circumvallate papillae
75
A receptor for changes in pressure
Baroreceptor
76
Explain lateral inhibition
Can further enhance sensory acuity
77
Receptor for pressure
Merkel's disk
78
Receptors for vibration
Pacinian corpuscle
Meissner's corpuscle
79
Neurotransmitters for nociceptors include ________
Substance p
80
Cranial nerves involved in gustation
CN VII, CN IX, CN X
81
4 major sensations of taste
Sweet
Bitter
Sour
Salty
82
Detection of chemicals in air
Olfaction (smell)
83
Only neurons in the adult human that replace themselves
Olfactory receptor cells
84
Cranial nerves associated with olfaction
CN I, CN V
85
Which structure does olfactory nerve pass through on their way to olfactory bulb
Cribriform plate
86
These sever input to the olfactory bulb and reduce or eliminate the sense of smell
Fractures of the cribriform plate
87
Which cranial nerve carries the smell of ammonia
CN V
88
Frequency of vibration (______)
Ultrasonic (____)
Infrasonic (_____)
20-20,000 Hz
>20,000 cycles per second
<20 cycles per second
89
The use of sound echoes to detect objects in the environment
Echolocation
90
The amplitude of sound waves is measured in _____
decibels (dB)
91
Pitch (tone)
Depends on the frequency
Intensity (loudness)
Depends on the amplitude
Timbre (quality)
Depends on overtones
92
The neural perception of vibrations in the air
Hearing
93
Pinna > eat canal > tympanic membrane > auditory ossicles
94
Parts of outer ear
Pinna (Auricle)
>collects and channels sound waves
External auditory meatus
>entrance into the skull
Tympanic membrane
>vibrates when struck by sound waves
95
Parts of middle ear
Air-filled chamber
Eustachian tube
>connected middle ear to pharynx
Auditory ossicles
>act as sound amplifies
-malleus = against tympanic membrane
-incus
-stapes = linked to oval window
96
2 regions in the inner ear
1. Vestibular apparatus
-equilibrium
2. Cochlea
-hearing
97
3 snail-shaped tubes filled with fluid
• Outer canals (continuous)
• scala vestibuli – superior
• links to oval window
• scala tympani – inferior
• links to round window
• inner canal = Cochlear Duct
• floor - organ of Corti
98
Waves of compressed and expanded air
Sound
99
Conduction of sound
1. Fluid pressure waves cause basilar membrane to vibrate
2. Hair cells move against tectorial membrane
3. Stimulates neurotransmitter release to sensory neurons
• Auditory nerve
4. Signals conducted to auditory cortex (temporal lobe)
100
Types of hearing loss
Conduction deafness
Sensorineural deafness
Central
101
Otolith organs
Utricle
Saccule
102
Labyrinth is made up of
Vestibular apparatus and cochlea
103
Bell-shaped structure at the end of each canal
Ampulla
104
Mound of hair cells covered with otolithic membrane
Macula
105
Otolith organ that respond to accelerations in the horizontal plane
Utricle
106
Otolith organ that respond to accelerations in the vertical plane
Saccule
107
Jerky back-and-forth movement of eyes
Nystagmus
108
Mismatch of vestibular and visual input
Motion sickness
109
Perception of electromagnetic radiation
Vision
110
Anatomy of the eye: outer layer, middle layer, inner layer
Sclera
Choroid
Retina
