Neurology Anatomy and Physiology Flashcards
1
Q
What is the function of oligodendroglia?
A
myelinates axons of neurons in CNS
2
Q
Can each oligodendrocyte myelinate more than one axon? If so, how many?
A
each oligodendrocyte can myelinate many axons, about 30 each
3
Q
Where are oligodendroglia derived from?
A
neuroectoderm
4
Q
What do oligodendroglia look like histologically
A
fried egg appearance
5
Q
What three diseases cause damage to the oligodendrocytes?
A
multiple sclerosis, progressive multifocal leukoencephalopathy (PML), leukodystrophies
6
Q
What type of sensory neuron fiber do free nerve endings have?
A
C-slow, unmyelinated fibers and Adelta-fast, myelinated fibers
7
Q
Where are free nerve endings located?
A
all skin, epidermis, some viscera
8
Q
What do free nerve endings sense?
A
pain, temperature
9
Q
What type of sensory neuron fiber do Meissner corpuscles have?
A
large, myelinated fibers that adapt quickly
10
Q
Where are Meissner corpuscles located?
A
Glabrous (hairless) skin
11
Q
What do Meissner corpuscles sense?
A
dynamic, fine/light touch, position sense
12
Q
What typ of sensory neuron fiber makes up Pacinian corpuscles?
A
large, myelinated fibers that adapt quickly
13
Q
Where are Pacinian corpuscles located?
A
deep skin layers, ligaments, joints
14
Q
What do Pacinian corpuscles sense?
A
vibration, pressure
15
Q
What type of sensory neuron fiber type makes up Merkel discs?
A
large, myelinated fibers; adapt slowly
16
Q
Where are Merkel discs located?
A
finger tips, superficial skin
17
Q
What do Merkel discs sense?
A
pressure, deep static touch (eg shapes, edges), position sense
18
Q
What type of sensory neuron fiber makes up Ruffini corpuscles?
A
dendritic endings with capsule that adapt slowly
19
Q
Where are Ruffini corpuscles located?
A
finger tips, joints
20
Q
What do Ruffini corpuscles sense?
A
pressure, slippage of objects along surface of skin, joint angle change
21
Q
What three layers make up the peripheral nerve?
A
endoneurium, perineurium, epineurium
22
Q
Define endoneurium
A
invests single nerve fiber layers
23
Q
What disease leads to inflammatory infiltrate in of endoneurium?
A
Guillan Barre syndrome
24
Q
Define Perineurium
A
surrounds a fascicle of nerve fibers (permeability barrier)
25
What layer of the peripheral nerve must be rejoined in microsurgery for limb reattachment?
perineurium
26
Define epineurium
dense connective tissue that surrounds entire nerve (fascicles and blood vessels)
27
Where is acetylcholine synthesized?
basal nucleus of Meynert
28
What two disease have a decrease in acetylcholine?
alzheimer disease and huntington disease
29
What disease has and increase in acetylcholine?
parkinson disease
30
Where is dopamine synthesized?
ventral tegmentum, SNpc
31
What diseases see an increase in dopamine?
schizophrenia and huntington disease
32
What diseases see a decrease in dopamine?
depression and parkinson disease
33
Where is GABA synthesized?
nucleus accumbens
34
What diseases see a decrease in GABA?
anxiety and huntington disease
35
Where is norepinephrine synthesized?
locus ceruleus
36
What disease has an increase in norepinephrine?
anxiety
37
What disease has a decrease in norepinephrine?
depression
38
Where is serotonin synthesized?
raphe nucleus
39
What disease has an increase in serotonin?
parkinson disease
40
What diseases show a decrease in serotonin?
anxiety and depression
41
What is the function of the blood brain barrier?
prevents circulating blood substances (eg bacteria, drugs) from reaching the CSF/CNS
42
What three structures form the blood brain barrier?
tight junctions between nonfenestrated capillary endothelial cells, basement membrane, astrocyte food processes
43
How do glucose and amino acids cross the blood brain barrier? quickly or slowly?
glucose and amino acids slowly cross the blood brain barrier by carrier mediated transport mechanisms
44
How do nonpolar/lipid-soluble substances cross the blood brain barrier? quickly or slowly?
nonpolar/lipid-soluble substances cross rapidly via diffusion
45
Name the few specialized brain regions with fenestrated capillaries and no blood-brain barrier allowing molecules in blood to affect brain function:
area postrema to cause vomiting after chemo, OVLT (organum vasculosum of the lamina terminalis) for osmotic sensing and neurosecretory products to enter circulation (eg neurohyphysis to ADH release)
46
Name two other notable barriers other than the blood brain barrier
blood-testis barrier and maternal-fetal barrier of placenta
47
What destroys endothelial cell tight junctions and leads to vasogenic edema?
infarction and or neoplasm
48
What is the function of the hypothalamus?
TAN HATS: Thirst and water balance, Adenohypophysis control (regulates anterior pituitary), Neurohypophysis releases hormones produced in the hypothalamus, Hunger, Autonomic regulation, Temperature regulation, Sexual urges
49
What are inputs to the hypothalamus (not protected by blood brain barrier)?
OVLT (organum vasculosum of the lamina terminus) sense changes in osmolarity, area postrema (found in medulla, responds to emetics)
50
What primarily makes ADH?
supraoptic nucleus
51
What primarily makes oxytocin?
paraventricular nucleus
52
What also makes ADH and oxytocin?
hypothalamus
53
How are ADH and oxytocin carried to the posterior pituitary?
ADH and oxytocin are carried by neurophysins down axons to posterior pituitary, where they are stored and released
54
What is the function of the lateral area?
Hunger
55
What happens in destruction of the lateral area?
anorexia, failure to thrive in infants,
56
What stimulates the lateral area? what in inhibits it?
the lateral area is stimulated by ghrelin and inhibited by leptin
57
What is the function of the ventromedial area?
satiety
58
What happens in destruction of the ventromedial area (eg cranipharyngioma)?
hyperphagia
59
What stimulates the ventromedial area?
leptin
60
What is the function of the anterior hypothalamus (clue: opposite of the posterior hypothalamus)?
cooling, parasympathetic
61
What is the function of posterior hypothalamus (clue: opposite of the anterior hypothalamus)?
heating, sympathetic
62
What is the function of the suprachiasmatic nucleus?
circadian rhythm
63
What regulates the suprachiasmatic nucleus?
light
64
What is the cascade that starts from the suprachiasmatic nucleus (SCN) to end with melatonin release?
SCN to norepinephrine to pineal gland to melatonin
65
What four things does circadian rhythm cause nocturnal release of?
ACTH, prolactin, melatonin and norepinephrine
66
What are the two stages of sleep?
rapid eye movement (REM) and non-REM
67
What causes the extraocular movements during REM sleep?
activity of the paramedian pontine reticular formation/conjugate gaze center PPRF
68
How often does REMP sleep occur throughout the night? and does it increase or decrease throughout the night?
every 90 minutes and increases in duration during the night
69
What is increased during REM?
Ach
70
What three substances are associated with decrease in REM sleep and delta wave sleep?
alcohol, benzodiazepines and barbituates
71
What leads to decreased during REM?
Norepinephrine
72
What do you use to treat bedwetting (enuresis)?
oral desmopressin (ADH analog); preferred over imipramine because of adverse effects
73
What is helpful in treating night terrors and sleepwalking?
benzodiazepines
74
What are the 4 stages of sleep?
awake (eyes open), awake (eyes closed), non-REM sleep (N1, N2, N3) and REM sleep
75
What percentage is in each stage of Non-REM sleep?
Stage N1 is 5%, Stage N2 is 45% and Stage N3 is 25%
76
Describe the awake stage of sleep?
alert, active mental concentration
77
What type of EEG waveform is associated with awake (eyes open)?
Beta (highest frequency, lowest amplitude)
78
What type of EEG waveform is associated with awake (eyes closed)
Alpha
79
Describe stage N1 of Non-REM sleep
light sleep
80
What type of EEG waveform is associated with N1?
Theta
81
Describe stage N2 of Non-REM sleep
deeper sleep; when bruxism (involuntary or habitual grinding of the teeth) occurs
82
What type of EEG waveform is associated with N2?
sleep spindles and K complexes
83
What type of EEG waveform is associated with N3?
delta (lowest frequency, highest amplitude)
84
Describe stage N3 of Non-REM sleep
deepest non-REM sleep (slow-wave sleep); when sleepwalking, night terrors, and bedwetting occur
85
What percentage of sleep is REM sleep?
25%
86
Describe REM sleep
loss of motor tone, increase use of brain oxygen, increase variable pulse and blood pressure; when dreaming, nightmares, and penile/clitoral tumescence (engorgement) occur; may serve memory processing function
87
What type of EEG waves during REM sleep?
Beta
88
What are all the wave forms during sleep?
Beta, Alpha, Theta, Sleep spindles and K complexes, Delta, Beta (at night BATS Drink Blood)
89
What is the input to the ventral posterolateral nucleus?
spinothalamic and dorsal columns/medial leminiscus
90
What is sensed in the ventral posterolateral nucleus?
pain, temperature; pressure, touch, vibration, proprioception
91
What is the destination of the ventral posterolateral nucleus?
primary somatosensory cortex
92
What is the input to the ventral posteroMedial nucleus?
trigeminal and gustatory pathway
93
What senses to the ventral posteroMedial nucleus?
Face sensation, taste
94
What is the destination of the ventral posteroMedial nucleus?
primary somatosensory cortex
95
What is the input to the lateral geniculate nucleus?
CN II (optic)
96
What is the sense of the lateral geniculate nucleus?
vision
97
What is the destination of the lateral geniculate nucleus?
calcarine sulcus
98
What is the input to the medial geniculate nucleus?
superior olive and inferior colliculus of tectum
99
What is sensed in the medial geniculate nucleus?
hearing
100
Where is the destination of the medial geniculate nucleus?
auditory cortex of the temporal lobe
101
What is the input to the ventral lateral nucleus?
basal ganglia, cerebellum
102
What is sensed by the ventral lateral nucleus?
motor
103
What is the destination of the ventral lateral nucleus?
motor cortex
104
Define the limbic system
collection of neural structures involved in emotion, long-term memory, olfaction, behavior modulation, ANS function
105
What structures make up the limbic system?
hippocampus, amygdala, fornix, mammillary bodies, cingulate gyrus,
106
What system is responsible for Feeding, Fleeing, Fighting, Feeling and Sex (famous 5 F's)?
Limbic system
107
What pathways are commonly altered by drugs (antipsychotics) and movement disorders (Parkinson disease)?
Dopaminergic pathways
108
What symptoms of altered activity do you see with the mesocortical pathway?
decreased activity (negative symptoms: flat affect, limited speech); limited effect by antipsychotic drugs
109
What symptoms of altered activity do you see with the mesolimbic pathway?
increased activity (positive symptoms: delusions, hallucinations)
110
What is the primary therapeutic target of antipsychotic drugs to decrease positive symptoms (eg in schizophrenia)?
mesolimbic system
111
What symptoms of altered activity do you see with the nigrostriatal pathway?
decreased activity (extrapyramidal symptoms: dystonia, akathisia-agitation, distress, restlessness-parkinsonism, tardive dyskinesia-involuntary movements)
112
Name the major dopaminergic pathway in the brain that significantly is affected by movement disorders and antipsychotic drugs
nigrostriatal pathway
113
What symptoms of altered activity do you see with the tuberinfundibular pathway?
decreased activity to increased prolactin to decreased libido, sexual dysfunction, galactorrhea, gynecomastia (in men)
