Neurology Flashcards
1
Q
Describe oculomortor nerve parasympathetic involvement in eye
A
Provides parasympathetic fibers to iris that reduces iris size
2
Q
Which cranial nerves provide parasympathetic innervation?
A
CNs 3, 7, 9, & 10
3
Q
List CNs responsible for opening & closing eyelids
A
Oculomotor (III) opens and facial (VII) closes
4
Q
Describe facial nerve parasympathetic involvement
A
Provides parasympathetic innervation to lacrimal and salivary glands
5
Q
This CN, b/c of its many branches, can be damaged with prolonged lateral recumbency
A
CN VII, facial
6
Q
Facial nerve sensory component serves
A
Lingual mucosa (taste)
7
Q
Syndrome whereby myoclonic seizures and generalized tonic-clonic seizures (GTCSs) are instigated by high frequency sounds
A
Feline audiogenic reflex seizures (FARS)
8
Q
FARS has reportedly responded better…
A
To levetiracetam than phenobarbital
9
Q
“Chewing” muscles innervated by
A
CN V, trigeminal nerve (mandibular branch)
10
Q
Provides motor input to tongue
A
CN XII, hypoglossal
11
Q
Provides motor input for muscles of throat, neck, and cranial back/shoulder
A
CN XI, accessory nerve
12
Q
The recurrent laryngeal nerve branches from the __ nerve
A
Vagus, CN X
13
Q
The fibers of the vagus nerve are primarily __, providing for functions such as ___ & ___
A
Motor; vocalization; swallowing
14
Q
The vagus nerve is associated with the __ branch of the autonomic nervous system.
A
Parasympathetic
15
Q
Stimulation of the vagus nerve causes
A
Decreased heart rate and increased gut motility
16
Q
The sensory fibers of the vagus nerve are associated with
A
Areas of the throat, thoracic, and abdominal viscera
17
Q
Inhibitory neurotransmitter that is a derivative of glutamic acid
A
Gamma-aminobutyric acid (GABA)
18
Q
Amino acids that are excitatory in the CNS
A
Glutamic acid and aspartic acid
19
Q
One subtype of EPSP glutamate receptor (named for other molecule it binds)
A
N-methyl D-aspartate (NMDA) receptor
20
Q
Inhibitory amino acid neurotransmitters
A
Glycine
Gamma-aminobutyric acid (GABA)
21
Q
Neurons of the peripheral nervous system (PNS) that conduct impulses away from the CNS are known as
A
Motor or efferent neurons
22
Q
The 2 major categories of motor/efferent neurons are
A
Somatic and autonomic
23
Q
The spinal cord white matter is composed of __ & __ fiber tracts
A
Ascending & descending
24
Q
The spinal cord white matter fiber tracts are named to indicate whether they are ___ or __
A
Ascending (sensory) or descending (motor) tracts
25
The names of the ascending spinal cord tracts usually start with ___ and end with __
Spino-; name of the brain region where the spinal cord fibers first synapse
26
The names of descending motor (spinal) tracts start with __ and end with __
The brain region that gives rise to the fibers and end with the suffix -spinal
27
Catecholamines are
Derived from tyrosine and are epinephrine, norepinephrine, and dopamine
28
Describe the relationship between ACh and myasthenia gravis
Muscle weakness in MG is due to the autoantibody-mediated ACh receptor destruction
29
The 2 types of ACh receptors
Nicotinic & muscarinic
30
Acetylcholine (ACh) is the neurotransmitter of all
Parasympatheic and sympathetic preganglionic fibers and all somatic motor neurons
31
The neurotransmitter released by most parasympathetic postganglionic fibers at their synapse with effector cells
Acetylcholine (ACh)
32
The neurotransmitter released by most postganglionic sympathetic nerve fibers is
Norepinephrine
33
In the sympathetic division of the autonomic nervous system, preganglionic fibers exit
The spinal cord from T1 to L2
34
In the parasympathetic division of the autonomic nervous system, the preganglionic fibers originate in
The brain and S2-S4
35
The 2 major classes of receptor proteins for catecholamine neurotransmitters
Alpha- and beta-adrenergic receptors
36
The 2 subtypes of the 2 adrenergic classes of receptors
Alpha-1 & alpha-2, beta-1 & beta-2
37
Adrenergic effect associated with alpha-1 receptors in the eye
Contraction of the radial fibers of the iris dilates the pupils
38
Adrenergic effects of beta-1 (primarily) receptor in the heart
Increase heart rate and contraction strength
39
Adrenergic effects of alpha-1 receptor in skin and visceral vessels
Arterioles constrict due to smooth muscle contraction
40
Adrenergic effects of alpha-1 receptor on skeletal muscle vessels
Arterioles constrict due to sympathetic nerve activity
41
Adrenergic effects of beta-2 receptor on skeletal muscle vessels
Arterioles dilate due to hormone epinephrine
42
Adrenergic effects of beta-2 receptors in lungs
Bronchioles dilate due to smooth muscle relaxation
43
Adrenergic effects of alpha-1 receptor on stomach and intestine
Contraction of sphincter slows passage of food
44
Adrenergic effects of alpha-1 & beta-2 receptors on liver
Glycogenolysis and secretion of glucose
45
The effects of ACh are always excitatory when released by
Somatic motor neurons and by preganglionic autonomic neurons
46
The effects of ACh released by post-ganglionic parasympathetic axons are
Usually excitatory but in some cases, inhibitory
47
Nicotinic ACh receptors are always
Excitatory
48
Some postganglionic autonomic axons do not involve ACh or norepinephrine, are called __, an example of which is__
Nonadrenergic/noncholingergic fibers; axons innervating the blood vessels of the penis
49
Atropine (belladonna) specifically blocks
Muscarinic ACh receptors
50
Stimulation of the radial muscles in the eye by ___ nerves causes __
Sympathetic; contraction of the radial muscles, which causes pupil dilation
51
Stimulation of the eye circular muscles by __ nerves causes __
Parasympathetic; causes circular muscle contraction, which constricts the pupils
52
The effects of the sympathetic and parasympathetic stimulation on the urinary and reproductive tracts are __
Cooperative
53
Organs without dual innervation (by sympathetic & parasympathetic nerves)
Adrenal medulla
Arrector pili muscles in the skin
Sweat glands in skin
Most blood vessels
54
Thermoregulatory responses to heat (and cold) rely on this autonomic system
Sympathetic
55
Disturbances in the state of consciousness are classified in order of severity as
depression, lethargy, obtundation, stupor (semicoma), coma
56
As a rule, altered states of consciousness relate either to a
Diffuse lesion or widespread multifocal lesions of both cerebral hemispheres, or a focal lesion affecting the ascending reticular activating system (ARAS) of the brainstem
57
The ascending reticular activating system (ARAS) of the brainstem functions to
Arouse the cerebral cortex and maintain the state of wakefulness
58
Paresis is defined as __ and implies __
A loss of ability to support weight (LMN disease) or inability to generate a gait (UMN disease); implies that some voluntary movement is still present
59
The term paralysis refers to a more severe __, with __
Paresis; with compete (-plegia) loss of voluntary movement
60
The cerebrum's contribution to the gait is less important __
Less important in in cats compared with primates
61
Cats often carry their tail elevated straight dorsally when
When they are suffering a significant loss of balance
62
A normal gait requires intact function of
Requires intact function of the brainstem, cerebellum, spinal cord, and sensory and motor peripheral nerves, neuromuscular junctions, and muscles
63
Ataxia definition
Is an uncoordinated gait
64
Ataxia can arise from
From a peripheral nerve or spinal cord lesion (general proprioceptive ataxia), a vestibular lesion (vestibular ataxia), or a cerebellar lesion (cerebellar ataxia)
65
Contrary to UMN peresis, disorders of the LMN do not cause __, only __
Ataxia, only paresis
66
Preferred postural reaction tests in felines
Wheelbarrowing and tactile placing
67
The hopping test is performed by
Restraining 3 limbs and suddenly lowering cat to floor. As soon as extended limb hits the floor, cats should be moved laterally to force him/her to hop on that limb. The thoracic limbs should be carefully compared.
68
A hopping movement should be
Smooth and fairly rapid, not irregular or excessive
69
Wheelbarrowing is performed with
The neck extended and the pelvic limbs elevated
70
In tactile placing, when the __ makes contact with ___, the cat should___
Campus makes contact with the edge of the table, the cat should immediately place his/her foot on the surface (neck extended to obscure view of table)
71
Postural reaction pathways (afferent & efferent)
Afferent arm: joint proprioceptor, peripheral sensory nerve, spinal cord and brainstem ascending pathways, contralateral forebrain
Efferent arm: contralateral forebrain, descending motor pathways within the brainstem and spinal cord, peripheral motor nerve and skeletal muscle
72
The UMN/LMN arrangement
The UMN system is confined to the CNS; the cell body of an UMN is in the cerebral cortex, basal nuclei, brainstem, or spinal cord. Nerve impulses travel through the brain &/or spinal cord white matter and synapse indirectly (via interneuron) with a LMN
The LMN cell body lies within the ventral horn of the spinal cord grey matter or within the cranial nerve nucleus of the brainstem. Its axon leaves the CNS by the ventral nerve roots to join successively a spinal nerve and a peripheral nerve before it synapses with an effector muscle
73
During gait generation, the UMN synapses indirectly with the LMN to
Modulate (essentially inhibit) its activity
74
Paraparesis/-plegia affects
Pelvic limbs affected
75
Monoparesis affects
Only 1 limb
76
Hemiparesis/-plegia affects
Limbs on 1 side
77
As. a continuation of the gait and postural reaction assessment, __ should be considered
Spinal reflex evaluation, but not as a sole entity
78
Following gait and postural reactions testing, the clinician should be able to
Narrow down the lesion localization to being Cr to T3 spinal cord segments, Cd to the T3 spinal cord segments, , or within the PNS (peripheral nerve, neuromuscular junction, or muscles)
79
Spinal reflex evaluation helps to narrow the lesion localization by
Testing the integrity of the C6 toT2 and L4 to S3 intumescences, as well as the respective segmental sensory and motor nerves that form the peripheral nerve, and the muscles innervated
80
Postural reaction tests
Hopping, wheelbarrowing, tactile placing (paw position/knuckling less preferred in cats)
81
Neuroanatomical diagnosis if gait/postural reactions decreased to absent in all 4 limbs
Generalized polyneuropathy/junctionopathy/myopathy
82
Neuroanatomical diagnosis if gait/postural reactions are decreased to absent bilaterally in pelvic limbs
L4-S3 spinal cord segments, peripheral nerve roots/nerves of pelvic limbs affected
83
Neuroanatomical diagnosis if gait/postural reactions decreased to absent in unilateral thoracic limb
Spinal cord segments C6-T2, or nerve roots, brachial plexus or peripheral nerves of affected limb
84
Spinal reflexes do not require __ & are __
Consciousness; segmental
85
The most reliable spinal reflex tests in cats
Withdrawal reflex and patellar reflex
86
In the thoracic limb, the withdrawal reflex test evaluates
C6-T2 & associated nerve roots, brachial plexus, peripheral nerves (radial, axillary, musculocutaneous, median and ulnar) & muscles innervated
87
In pelvic limb the withdrawal reflex test evaluates
L4-S1 spinal cord segments and associated nerve roots, femoral and sciatic nerves and muscles innervated
88
In nociception testing, limb withdrawal is only the flexor reflex and should not __
Should not be interpreted as evidence of pain perception
89
The patellar reflex test evaluates the integrity of
The L4-L6 spinal cord segments, associated nerve roots, and femoral nerve
90
Cats with stifle disease can exhibit a weak or absent __
Patellar reflex
91
An exaggerated patellar reflex can appear
With a lesion cranial to the L4 spinal cord segment
In an excited/nervous cat (in absence of other neurologic signs)
92
A pseudo-hyperreflexia of the patellar reflex can occur
In a cat with a sciatic nerve or L6-S1 spinal cord segment lesion (due to decreased muscle tone in the muscles that flex the stifle and normally counteract stifle extension during the patellar reflex)
93
The menace response can be
Particularly difficult to elicit in a normal cat and its absence should be interpreted with caution
94
When the menace response is questionable, try
Visual placing response
95
Anisocoria and dyscoria definitions
Anisocoria: pupils of unequal size
Dyscoria: pupils of unequal shape
96
The motor function of CN V can be assessed by __
Evaluating the size and symmetry of the masticatory muscles and testing the resistance of the jaw to opening the mouth
97
The palpebral reflex test evaluates
Sensory function of CN V ophthalmic branch (medial canthus) and maxillary branch (lateral canthus)
98
The Schirmer tear test can evaluate the (neuro)
Parasympathetic supply to the lacrimal gland associated with CN VII
99
The motor innervation of CN VII can be assessed by ___
Observing for movement of the ears, eyelids, lips, and nostrils and lip symmetry
100
As with the menace response, the response to nasal stimulation requires an intact
Contralateral forebrain
101
CN VIII can be evaluated by ___, and more specifically by __
Observing the cat's body and head posture at rest, and evaluation of his/her gait, and more specifically by testing the oculovestibular reflex and looking for pathologic nystagmus
102
Nystagmus is defined as __ and is either __ or ___
An involuntary rhythmic movement of the eyeballs; it is either physiologic or pathologic
103
The oculovestibular reflex can be evaluated by
By rotating the head from side to side (in a cat, hold him/her at arm's length and rotate side to side)
104
In the absence of any head movement, nystagmus should __
Never be present in a normal animal
105
The 2 types of observable nystagmus in a cat are __
Spontaneous (when head is at rest) and/or positional (when the head is held in different positions)
106
Nystagmus is classified based on
Its direction (the fast movement), as horizontal, vertical, or rotatory
107
In disorders of the peripheral components of the vestibular system in the inner ear, the direction of the nystagmus is always __
Always opposite to the side of the lesion and is usually horizontal or rotatory
108
Lesions of the central components of the vestibular system can cause pathologic nystagmus in __
In any direction, and occasionally it changes direction with different positions of the head
109
A vertical nystagmus is most commonly due to
A central lesion
110
Common changes in a patient's level of awareness and behavior include ___, signs which reflect disturbances in the __
Disorientation, aggression, vocalizing, circling, compulsive walking or head pressing reflect disturbances in the ascending reticular activatiing system (ARAS) and limbic system components of the cerebrum or postural brainstem
111
Circling can be caused by lesions in the
Vestibular system as well as an asymmetrical or focal lesion in the forebrain
112
A head tilt is associated with
A vestibular disorder
113
A head turn is associated with
An ipsilateral forebrain lesion
114
Ventroflexion of the neck is associated with
A neuromuscular disorder or severe cervical spinal cord grey matter lesion
115
Evaluation of a patient with an abnormal gait should be done with the aim of determining if the patient is __
Ataxic, paretic, or lame (neuromuscular or orthopedic disorder)
116
The neuroanatomical localization in all cats with seizures (regardless of the cause) is
The forebrain: seizures are the manifestation of hyper synchronous abnormalmneuronal activity originating in the cerebral
117
The features of focal seizures in cats are more variable than __ and include
Those in dogs and include drooling, facial movements, hippus, excessive vocalization/growling, random skittish behavior, and abnormal head, neck, or limb movements
118
The vital phase of a generalized seizure generally lasts __ in cats
1 to 3 minutes
119
Focal seizures may occur ___ and may progress to
Several times throughout the day; progress to generalized seizurez
120
Generalized seizures may progress
To a state of status epilepticus
121
Cats with idiopathic epilepsy tend to be ___ than cats with secondary epilepsy and have a __
Younger (~3.5 years, vs ~8 years with secondary epilepsy); longer median survival time
122
In cats presenting for seizures, normal neurologic exam findings do not rule out __
Structural brain disease, especially if the lesion is in a "silent" region of the brain
123
Cats with large cerebral masses and increased cranial pressure may have __
Cerebellum herniation through the foramen magnum
124
Cats with a cerebellum herniation through the foramen magnum may present with __
Acute onset of cerebellar signs including a hypermetric/ataxic gait with normal general proprioception, intention tremors, and a decreased menace response with normal vision
125
Abnormalities in CSF are very sensitive __
Indicators of intracranial disease, but are often not specific.
126
Normal CSF is __
Clear and colorless with < 5 cells/uL and < 27 mg/dL protein (cisterns mag a tap)
127
An antiepileptic drug is considered effective if it __
Reduces seizure activity by 50% or more
128
Oral diazepam in cats is
Contraindicated (AAFP) because of associated potentially fatal hepatotoxicosis
129
Eicosanoids are
Mediators of peripheral sensitization
130
Central sensitization occurs when
Pain thresholds are reduced following tissue damage, caused by repeated stimulation that alters the nociceptive pathways.
131
The main sites of central sensitization are
The dorsal horn, and higher centers of the brain, especially the cerebral cortex
132
Hyperalgesia
Increased pain due to stimulation of damaged tissue by a stimulus that would normally be perceived as painful. The stimulation is felt as more painful than it normally would (if the tissue were not damaged).
133
Clinical signs of central and peripheral sensitization
Hyoeralgesia and allodynia
134
Allodynia
Pain due to stimulation of damaged tissue by a stimulus that would not normally be perceived as painful. The stimulation is felt as painful because the tissues are damaged
