Neurophysiology Flashcards
(133 cards)
1
Q
Pain of visceral origin that follows the dermatome rule?
A
Referred pain
2
Q
Increased in what motor neuron activity increases the sensitivity of the muscle spindle?
A
Gamma - motor neuron activity
3
Q
An exaggerated form of the Golgi tendon reflex?
A
Clasp-knife Reflex
4
Q
Autonomic receptor blocked by hexamethonium at the ganglia but not at the neuromuscular junction?
A
Cholinergic nicotinic receptors
5
Q
Blocks Nicotinic receptors only in the ganglia and not in the NMJ?
A
Hexamethonium
6
Q
True or False.
Nicotinic receptors are present in both ganglia and NMJ?
A
True
7
Q
66/M with chronic hypertension treated with prazosin. Mechanism of action of the drug?
A
Inhibition of a-1 receptors on vascular smooth muscle leading to vasodilation of cutaneous and splanchnic vascular beds , decreased TPR and decreased BP.
8
Q
Parasympathetic muscarinic receptor effect on the eyes?
A
Miosis - contraction of the circular muscle of the iris
9
Q
Unique feature of C fibers compared to other types?
A
Have the slowest conduction velocity of any nerve fiber type.
10
Q
Compared with the cones of the retina , the rods are more sensitive to?
A
Low intensity light
11
Q
The apex of the organ of Corti responds to which frequency?
A
The apex responds better to low frequencies than the base does.
12
Q
Origin of sympathetic preganglionic neurons?
A
Originates in the Thoracolumbar Spinal cord
13
Q
The apex of the organ corti responds to which frequency?
A
The apex responds better to low frequencies than the base does
14
Q
Autonomic receptors that mediates increased in heart rate?
A
Adrenergic B-1 Receptors
15
Q
Total blindness of the left eye. Structure damaged?
A
Left optic nerve
16
Q
Reflex responsible for monosynaptic excitation of ipsilateral homonymous muscle
A
Stretch reflex ( myotactic)
17
Q
Cells in the visual cortex that responds best to moving bar of light?
A
Complex Cells
-respond to moving bars or edges with correct orientation.
18
Q
Cell in the visual cortex respond to stationary bars?
A
Simple cells
19
Q
Cell in the visual cortex respond to lines, curves, and angles?
A
Hypercomplex cells
20
Q
Drug/ Drug class contraindicated in a child with history of asthma?
A
Propranolon ( Beta 2- antagonist)
Will cause further bronchoconstriction from an already increased resistance in asthma.
21
Q
Stimulatory adrenergic receptor that forms IP3 and an increase in intracellular Ca?
A
Alpha 1 receptor
22
Q
The excessive muscle tone produced in decerebrate rigidity can be reversed by ?
A
Cutting the dorsal roots blocks the reflexes since decerebrate rigidity is caused by increased reflex muscle spindle activity.
23
Q
Body part with the largest representation on the primary motor cortex?
A
Fingers
24
Q
Autonomic receptor that mediates secretion of epinephrine by the adrenal medulla?
A
Cholinergic nicotinic receptors
25
Blindness in the temporal field of the left eye and nasal field on the right eye. What structure is damaged?
Right optic tract ( homonymous contralateral hemianopia )
26
A dancer spins to the left and eyes snap quickly to the left. This fast eye movement is called?
Nystagmus
Occurs in same direction as the rotation.
27
A dancer spins to the left and eyes snap quickly to the right. This fast eye movement is called?
Postrotatory Nystagmus
28
Autonomic drug that stimulates adenylate cyclase?
Choices:
atropine , clonidine, curare, norepinephrine, phentolamine, or propranolol.
Norepinephrine
among the autonomic drugs only B1 and B2 act by stimulating adenylate cyclase.
Atropine - Muscarinic cholinergic antagonist
Clonidine- alpha 2 agonist
Curare- Nicotinic cholinergic antagonist
Phentolamine - alpha 1 antagonist
Propranolol- B1 & B2 antagonist
29
Activates transducing in photoreception?
Metarhodopsin II
Activates transducing
30
Effects of pathogens in producing fever?
Increase Interleukin 1
1. Increase prostaglandins
2. Increase in set point temperature
3. Shivering
4. Vasoconstriction of blood vessels
31
True or False.
Olfactory receptor cells are considered neurons.
True, and the only neurons that regenerate.
32
Effect of chorda tympani lesion.
Impaired taste function
33
Produces maximum excitation of the hair cells in the right horizontal semicircular canal?
Rotating the head to the right
34
In Disdiadokinesia , what organ or structure is affected?
Cerebellum
35
Autonomic receptor activated by low concentrations of epinephrine causing vasodilation .
Adrenergic Bata-2 receptors
36
Complete transection of the spinal cord at the level of T1 would most likely result in ?
Temporary loss of stretch reflex below the lesion.
Transection of spinal cord causes spinal shock and loss of all reflexes below the level of the lesion.
37
Definition of sensory receptor potentials?
Are graded in size depending on stimulus intensity.
May bring the membrane potential of the receptor cell either toward (depolarization) or away (hyperpolarization)
38
Tru or False.
Receptor potentials are not action potentials.
True
39
Blindness in the temporal fields of the left and right eyes. What structure is damaged?
Optic chiasm ( bitemporal hemianopia)
40
Primary function is to coordinate rate, range, force, and direction of movement?
Cerebellum
41
Reflex responsible for polysynaptic excitation of contralateral extensors?
Flexor withdrawal reflex
42
Function of nuclear bag fibers?
They detect dynamic changes in muscle length.
43
Function of Nuclear chain?
Detect static changes.
44
Muscle stretch leads to a direct increase in firing rate of this type of nerve?
Group Ia fibers
45
42 / F with Pheochromocytoma treated with phenoxybenzamine. What is the moa of the drug?
Decrease IP3 / Ca 2+ , phenoxybenzamine is an a-1 antagonist , thus decreasing IP3 / Ca2+
46
Effect of atropine on AV node conduction velocity.
Increased AV node conduction velocity.
Muscarinic receptors decreases AV Node conduction, thus muscarinic antagonists agents such as atropine , will increase AV node conduction velocity.
47
What waves in the EEG in a person with closed eyes but awake?
Alpha waves
48
Nerve affected in claw hand?
Ulnar Nerve
49
Nerve affected in wrist drop?
Radial Nerve
50
Nerve affected in ape hand/ Hand of benediction?
Median Nerve
51
Parkinsons:
Mechanism ?
Location in the brain ?
NT affected ?
Mechanism: degeneration of dopaminergic neurons
Location: Substantia nigra pars compacta
NT affected: Dopamine
52
Heteronymous bitemporal hemianposia?
Optic chiasm
53
Innervated by alpha- motoneurons, for voluntary muscle contraction?
Choices: Intrafusal or Extrafusal
Extrafusal
54
Blocked by hexamethonium at the ganglia but not in the NMJ?
Cholinergic Nicotinic Receptors
55
Which reflex is responsible for monosynaptic excitation of ispsilateral homonymous muscle?
Stretch reflex (Myotatic)
56
Sleep cycle rhythm/ waves?
Alpha, Beta, Delta, Theta
57
Location of the blindspot?
A. 12-15 degrees temporally
B. 1.5 degrees below the horizontal meridian
C. 7.5 degrees high
D. 5.5 degrees wide
58
Neostigmine moa?
Inhibits Acetylcholinesterase (AchE)
59
Hexamethonium moa?
Non-depolarizing ganglionic blocker
60
Innervation anterior 2/3 tongue?
CN VII ( Chorda tympani Facial Nerve)
61
Releases NO?
Nonadrenergic , Noncholinergic Neurons
62
Substance P is inhibited by?
Opioid
63
Decreases pupillary aperture?
Miosis
64
Drooping of eyelid?
Ptosis
65
Muscle that contracts during knee-jerk reflex / patellar reflex ?
Quadriceps femoris ( Extensor Muscle)
- located taas sa patella
66
Salivation after seeing a roasted pig is caused by?
Parasympathetic nervous system
- cephalic phase of gastric secretion also occurs at this time
67
Most potent mechanism for heat production ?
Shivering ( behavioral response)
68
Diseases involving Dopamine?
1. Parkinsons - decreased
2. Schizophrenia - increased
69
Diseases involving Acetylcholine?
1. Myasthenia gravis- autoantibodies against acetylcholine
2. Alzheimers- decreased
70
Characteristics of cerebral blood flow (CBF) ? (4)
1. CBF is related to metabolism of cerebral tissues
2. H+ causes increased blood flow vasodilation
3. O2 utilization by the brain is within narrow limits
4. Increased CBF will increase removal of acids
71
Characterizes the corticorubrospinal system? (4)
1. Serves as an accessory route for transmission of discrete signals
2. Ends on the interneurons and motor neurons that control the more distal muscles of the limbs
3. Stimulation of a single point in a portion of the red nucleus will cause contraction of a single muscle
4. Humans have small and rudimentary red nucleus
72
Clasp knife reflex?
Golgi Tendon Reflex - characteristic UMN lesion response
73
Visual defect from cutting the optic nerve ?
Blindness in the ipsilateral eye
74
Blocks the release of Ach from presynaptic terminals?
Botulinum toxin
75
Reflex involving flexion on ipsilateral side and extension on contralateral side?
Flexor - Withdrawal Reflex
76
Homonymous hemianopia with macular sparing involve ?
Calacrine fissure
77
Summate to form endplate potential (EPP)?
Miniature End-Plate potential
EPP is an efficient action potential that involves depolarization of the specialized muscle end plate.
78
Functions of neurotransmitters in the CNS?
Chemical messengers
79
Types of cells in the CNS? (2)
1.neurons
2.glial cells
80
Micturition center?
Pons
81
Respiratory center ?
Medullary ( DRG & VRG)
82
Apneustic center when stimulated will cause?
Prolongs duration of inspiration -> decreased RR
83
Occurs in REM sleep?
1. Dreams
2. Miosis
3. Erection
4. Occurs every 90mins of slow wave sleep
5. Rapid eye movement
6. Difficult to arouse
84
When a vascular smooth muscle are stretched , there’s a reflex contraction and vice versa. May explain auto regulation , but not active or reactive hyperemia.
Myogenic Theory
85
Helps in regeneration and remyelination in thePNS?
Schwann cells
86
Stimulate flexors and primarily extensor muscles predominates the medullary counterpart?
Pontine Reticulospinal Tract
87
Neurotransmitters of the enteric nervous system?
1. Acetylcholine (major)
2. Dopamine
3. Serotonin
88
Main function of CSF?
Cushioning
89
Location of Rods and Cones?
Retina
90
Important eye movement?
Blinking
91
Ciliary muscle contraction?
Spherical lens ( focus on near objects, accommodation)
92
2 functional classes of eye movements?
Gaze stabilization& Gaze shifting
93
Type of hearing loss when you damage the inner hair cells?
Irreversible sensorineural hearing loss
( usually affecting first those involved in high-frequency sounds)
94
Rapid alternating movements?
Dysdiadochokinesia
95
Parts of the brain involved in hunger?
Lateral (hunger) nuclei
Ventromedial (satiety) nuclei of the hypothalamus
96
MOA of hexamethonium?
Non-depolarizing, ganglionic blocker
(Nicotinic not in NMJ )
97
Corrective lenses for Myopia ?
Biconcave
98
Corrective lenses for Hyperopia ?
Convex
99
Corrective lenses for Astogmatism ?
Cylindrical
100
Uses group Ia afferents , detects dynamic changes?
Nuclear bag fibers
101
Approximate number of neurons?
100 Bilion
102
Involve in interhemispheric communication?
Corpus callosum
103
Gas that is always an inhibitory NT, can vasodilate arterioles, involves cGMP?
Nitric Oxide
104
LH is highest in what phase of cycle?
Ovulation
105
Part of the brain you need the most to catch a fly?
Cerebral cortex
106
Conduction velocity is most dependent on?
Nerve diameter ( more than myelination)
107
Form red nucleus to interneurons of lateral spinal cord. Stimulates flexors , inhibits extensors ?
Rubrospinal Tract
108
Location of GABA C Receptors?
Retina
109
Greatest resistance in the blood vessels?
Arterioles
110
Putamen and anterior horn cells are involved in?
Motor pathways
111
Also known as the craniosacral division?
Parasympathetic Nervous System
112
What facilitates release of Ach from the synaptic vesicles?
Ca influx
113
Autoimmune disease marked by auto-antibodies against this voltage gated calcium channels which prevents Ach from being released to the NMJ?
Lambert-Eaton Myasthenic Syndrome
114
Compression of eyeballs / EOMS leading to decreased HR?
Oculocardiac Reflex/ Aschner Phenomenon/ Ashner-Dagnini Reflex
115
Cause HCl secretion while food is in stomach?
Vagovagal Reflex
116
Appetite & Satiety centers are found in which part of hypothalamus respectively?
Lateral (Appetite)
Ventromedial ( Satiety)
117
Used for night vision?
Rods
118
Triggers the chemoreceptor trigger zone found in the area of postrema?
1. Emetics
2. Radiation
3. Vestibular stimulation
119
Chemoreceptors react to which stimulus ? (2)
1. Peripheral chemoreceptors in aortic bodies, carotid bodies:
-hypoxemia (main)
-hypercarbia
-acidosis
2. Central chemoreceptors in medulla: CSF H+
120
Which nerve when damaged cause gluteal / tendelenburg gait?
Superior Gluteal Nerve
Tendelenburg gait: mo drop ang pelvic bone while ga walk
121
No action potential possible even with increased stimulus?
Absolute Refractory Period
122
In comparison to skeletal muscle cells, cardiac muscle cells contain more __________?
Sarcosomes ( large specialized mitochondria)
123
Types of GABA receptors? (3)
1. GABA A : ionotrophic ; ubiquitous
2. GABA B : metabotropic
3. GABA C: ionotropic , enriched in retina compared to other parts of CNS
124
After a rapid spin to he right , eyes quickly snap in the same direction?
Nystagmus
125
Triggers of malignant hyperthermia?
1. Halothane also inhaled general anesthesia : enflurane, ether, isoflurane, sevoflurane)
2. Succinylcholine
3. Heat stress
4. Vigorous exercise
126
Polysynaptic reflex? (3)
1. Flexor - withdrawal reflex: ( touching hot pan , flexon on the affected arm, extension in contralateral)
2. Golgi- Tendon / Clasp Knife Reflex: disynaptic , UMN lesion
3. Stretch/ Knee-jerk Reflex : monosynaptic , quadriceps femoris tendon is responsible for the jerking
127
Physiologic blind spot?
Optic disc
128
Brain waves predominate during awake, eyes closed, relaxing person?
Alpha- waves
129
Brain waves predominate during awake, eyes closed, relaxing person?
Alpha- waves
130
Brain waves predominate during awake, eyes open, busy and alert?
Beta waves
131
Brain waves predominate during brain disorders and degenerative brain states?
Theta waves
132
Brain waves predominate during brain disorders and degenerative brain states?
Theta waves
133
Brain waves predominate during deep sleep, and organic brain disease and in infants ?
Delta waves
