Neuro 2 Flashcards

1
Q

Where are the sympathetic cell bodies located?

A

T1-L2 spinal ganglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the sympathetic NS used as preganglionic neurotransmitter & what is the receptor for this?

A

ACh

Nicotinic cholinergic receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the sympathetic NS used as postganglionic neurotransmitter & what is the receptor for this?

A

Adrenaline

Adrenergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where are the parasympathetic cell bodies located?

A

Sensory ganglia of cranial nerves 3,7,9,10 & spinal nerve ganglia S2-S4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the parasympathetic NS use as its preganglionic & postganglionic neurotransmitter and what are the receptors for this?

A

ACh
Cholinergic
Pre = nicotinic cholinergic
Post = muscarinic cholinergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the 3 main types of neurones?

A

Unipolar - cell body as projection from axon
Bipolar - cell bodies in middle of axon
Multipolar - cell bodies in centre of dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 functional types of neurons?

A

Afferent - sensory to CNS
Efferent - CNS to tissues
Interneurons - within CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the CNS myelinated by?

A

Oligodendrocytes (type of glial cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the PNS myelinated by?

A

Schwann cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the purpose of myelination?

A

Acts as insulating later to prevent movement of Na+ & K+ across axon
Nodes of Ranvier act to propagate action potential faster by saltatory conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What moves substances along an axon?

What are the 2 proteins involved in transport & in which direction do they move substances?

A

Microtubules & proteins
Microtubules made from proteins
Kinesins - transport substances away from cell body (anterograde transport)
Dyneins - transport substances towards cell body (retrograde transport)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 4 main types of glial cell?

A

Oligodendrocytes - myelination of CNS
Astrocytes - BBB, role in control of brain ECF composition, metabolically support neutrons
Microglia - macrophage like
Ependymal cells - line ventricles & regulate production of CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the refractory period of an action potential?

A

The period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation due to Na+ channels already being open

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the purpose of a refractory period?

A

To insure the impulse travels in only 1 direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the speed of an action potential determined by?

A

Axon diameter

Myelination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 2 structures of the external ear?

A

Auricle

External acoustic meatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where does the middle ear lie?

A

Within the temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 4 main parts to the middle ear?

A

Tympanic membrane
Auditory ossicles - malleus, incus, stapes
Muscles (contract to protect from loud noises) - tensor tympani, stapedius
Auditory tube - middle ear to nasopharynx, equates pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the tensor tympani innervated by?

A

Mandibular, CNV3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the stapedius innervated by?

A

Facial, CNVII

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where does the inner ear lie?

A

Within the petrous part of the temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the 3 main parts of the inner ear?

A

Bony labyrinth - bone cavities filled with perilymph
Membranous labyrinth - ducts within bony filled with endolymph
Oval window

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the 3 parts of the bony labyrinth?

A

Vestibule - central part
Cochlea - houses cochlear duct
Semicircular canals - contain semicircular ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does the spiral lamina do?

A

Projection from centre of cochlea that divides cochlea into 2 chambers
Scala vestibuli superiorly
Scala tympani inferiorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the 2 parts of the membranous labyrinth?

A

Vestibular system - semicircular ducts, saccule, utricle

Cochlear duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the purposes of the organ of Corti?

A

Conversion of pressure changes in cochlea into electrical impulses sent to the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the differences between the region of the cochlear duct that experiences maximum displacement according to frequency?

A

Higher - vibration of part closest to oval window

Lower - vibrations travel further along scala vestibule & vibrate more distal sections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the hair cells?

A

Mechanoreceptor cells that have hair-like projections from the top of them (stereocilia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How do vibrations cause an electrical impulse?

A
  • Stereocilia in contact with tectorial membrane that overlies organ of Corti & remains stationary during vibrations
  • Pressure waves cause displacement of basilar membrane
  • Hair cells move & sterocilia bend
  • Tip links between ends stretched
  • Physically opens mechanically-gated ion channels
  • Influx of K+ (surrounding endolymph is K+ rich)
  • Depolarisation
  • Voltage gated Ca2+ channels near base open
  • Glutamate released into space between hair cell & afferent neutron fibres
  • Form cochlear branch of CNVIII
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the auditory pathway?

A

Internal acoustic meatus > ipsilateral cochlear nucleus complex > trapezoid body > contralateral superior olivary nucleus > lateral lemniscus > inferior colliculus > medial geniculate body > primary auditory cortex
I’M AUDITORY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How do the semicircular canals detect acceleration?

A

The canals move & the endolymph doesn’t
Inside surface of canals move against fluid
Bending of sterocilia
Stimulation of afferent neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the sterocilia in the semicircular canals ensheafed by?

A

Cupula, a gelatinous mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What makes the hair cells more easily subject to gravity in the utricle & saccule?

A

Calcium carbonate crystals, otoliths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What 3 nuclei make up the vestibular nuclei?

A

Medial - semicircular canal
Superior - semicircular canal
Lateral - utricle & saccule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the function of the basal ganglia?

A

Controls movements by facilitating & inhibiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What do the direct & indirect pathways do?

A

Direct - make & maintain movements

Indirect - inhibits & prevents movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are 2 disorders of the basal ganglia?

A

Parkinson’s disease (not enough dopamine)

Huntington’s disease (too much dopamine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is a motor end plate?

A

A region of muscle fibre’s plasma membrane that lies directly beneath an axon’s terminal plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is a neuromuscular junction?

A

Junction of axon terminal & motor end plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the difference between synapses & NMJs?

A

All action potentials in motor neurone usually trigger an AP in muscle fibres
All NMJs are excitatory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What extra-ocular muscles originate from the common tendinous ring?

A

Rectus x4

Superior oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are the 4 stages of an action potential?

A

1) resting potential = Na+/K+atpase pump pumps 3Na+ out & 2K+ in; some K+ diffuses out
2) depolarisation = stimulus causes some Na+ channels to open; Na+ influx
3) repolarisation = some K+ channels open & Na+ channels close; K+ diffuse out
4) hyperpolarisation = K+ slow to close; overshoot; helps refractory period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is a synapse?

A

A junction between 2 neurons where the electrical activity in the presynaptic neuron influences the activity in the post-synaptic neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are the 2 types of synapse?

A

Chemical - excitatory, inhibitory, modulatory

Electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What is convergence? (synapse)

A

Many presynaptic neurons influencing one postsynaptic neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is divergence? (synapse)

A

One presynaptic neurone influences many postsynaptic neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are the 7 stages of transmission across a synapse?

A

1) AP depolarises pre-synaptic axon terminal membrane
2) Na+ voltage-gated channels open & influx
3) Ca2+ channels open & influx
4) synaptic vesicles fuse with presynaptic axon terminal & release contents by exocytosis
5) neurotransmitters in synaptic cleft & diffuse across
6) bind to receptor proteins on post-
7) ligand gated ion channels open & propagate AP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What are 3 ways of neurotransmitter termination?

A

Reuptake by astrocyes/presynaptic terminal
Destroyed by enzymes
Diffuse away from site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are glutamate & GABA in the brain?

A

Neurotransmitters
Glutamate - excitatory
GABA - inhibitory

50
Q

What is the definition of pain?

A

An unpleasant sensory & emotional experience associated with actual or potential tissue damage

51
Q

Define referred pain

A

Sensation of pain is experienced elsewhere to where the stimulus is

52
Q

What are 2 classifications of pain relating to time?

A
Acute = <12 weeks, typical
Chronic = >12 weeks, longer than expected for stimulus
53
Q

What are the 2 types of chronic pain?

A

Cancer

Non-cancer

54
Q

What are 2 other classifications of pain?

A
Neuropathic = pain caused by damage/disease affecting somatosensory NS
Nociceptive = pain caused by stimulus damaging tissues that is detected by nociceptors, non-neural tissue
55
Q

What is the method of feeling pain?

A
  • Nociceptors stimulated in an injury
  • Tissue damage releases bradykinin & prostaglandin E2, which reduce the nociceptive threshold & increases sensitivity to stimuli
  • Nociceptor afferent nerves release substance P, a neurotransmitter that causes long lasting excitatory post-synaptic potential to help sustain the effect of noxious stimuli
56
Q

Where does the process of pain begin & what tracts does it involve?

A

Dorsal horns

Lateral spinothalamic tracts

57
Q

What is a nociceptor?

A

A sensory neutron found in any tissue capable of experiencing the sensation of pain

58
Q

What is analgesia?

A

Selective suppression of pain without any effect on consciousness
eg paracetamol
Doesn’t eliminate sensation

59
Q

What is an anaesthetic?

A

Substances which induce insensitivity to pain

Reversible loss of sensation

60
Q

What are the differences between A delta and C fibres?

A

A delta - mechanical & thermal; thinly myelinated; larger diameter; sharp acute specific pain; faster

C - mechanical & thermal & chemical; non-myelinated; smaller diameter; diffused dull later pain; slower; 70% of nociceptive fibres

61
Q

What is periaqueductal grey?

A

Grey matter around the cerebral aqueduct
Receives input from cortical & sub-cortical areas
Modulates afferent noxious transmission
Primary control centre for descending pain modulation
Has opioid receptors - can result in analgesia

62
Q

What is the area postrema?

A

Part of medulla outside BBB
Can detect toxins & act as vomit inducing centre
Densely vascularised without tight junctions

63
Q

What is the Melzack-Wall pain gate theory?

A

Non-painful input closes the ‘gates’ to painful input which therefore prevents pain sensation from travelling to the CNS
eg massage, ice packs

64
Q

Where are the 4 main areas of pain recognition?

A

Thalamus
Somatosensory cortex
Insula cortex (in lateral sulcus, judges degrees of pain, subjective)
Periaqueductual grey

65
Q

How do opoids produce their effects?

A

Occupy receptors on pre-synaptic neurones to cause an inhibitory membrane potential & prevent the release of substance P

66
Q

What are endorphins?

A

Naturally occurring peptides that have opiate like effects

67
Q

What is substance P

A

Neurotransmitter used for transmission of pain information into CNS

68
Q

What is a motor unit?

A

A single alpha neutron & all of the muscle fibres it innervates

69
Q

What is a motor neurone pool?

A

A collection of motor neurone innervating a single skeletal muscle

70
Q

What does a golgi tendon detect?

A

Changes in muscle tension

71
Q

What are golgi tendons innervated by & what are they made of?

A

Sensory 1b neurons

Network of collagen fibres inside a connective tissue capsule

72
Q

What does a muscle spindle detect?

A

Stretch of a muscle

73
Q

What are muscle spindles innervated by & what are they made of?

A

Sensory 1a neurons

Intrafusal fibres

74
Q

What is Brown-Sequard syndrome?

A

Hemisection of spinal cord

75
Q

What are the symptoms of Brown-Sequard syndrome?

A

Loss of contralateral pain & temperature (spinothalamic)

Loss of ipsilateral motor & fine touch (descending motor tracts, DCML)

76
Q

What is the visual pathway?

A

Eyes > optic nerve > optic chasm > optic tract > lateral geniculate nuclei > optic radiations > primary visual cortex

77
Q

Which visual fields cross over?

A

Nasal

78
Q

What is Meyer’s loop

A

Travels inferiorly to Baum’s loop through temporal lobe

Carries information from inferior retina (superior visual field)

79
Q

What lies within the outer eye? (2)

A

Cornea (clear, protective, refraction)

Sclera (tough, attachment for muscles)

80
Q

What lies within the middle eye? (3)

A
Iris (pupil)
Ciliary body (produces aqueous humour, alters shape of lens)
Choroid plexus (blood supply)
81
Q

What lies within the inner eye? (1)

A

Retina (transduction of light)

82
Q

What are the 10 layers of the retina from superficial to deep?

A

1) internal limiting membrane
2) nerve fibre (axon of ganglions)
3) ganglion cell
4) inner plexiform
5) inner nuclear
6) outer plexiform
7) outer nuclear
8) external limiting membrane
9) photoreceptor
10) retinal pigment epithelium

83
Q

What are the differences between rod & cone cells?

A

Rods - light, more abundant, better sensitivity

Cones - colour & visual acuity

84
Q

What is the levator palpebral superioris innervated by?

A

Oculomotor CNIII

85
Q

What is the purpose of the round window of the ear?

A

Allows fluid in the cochlea to move

86
Q

What are the 3 scala of the middle ear?

A

Scala media
Scala tympani
Scala vestibuli

87
Q

What are the differences between inner and outer hair cells?

A
Inner = one row, afferent fibres, transmit auditory stimuli
Outer = more numerous, 2/3 rows, efferent fibres, modulate inner hair cells
88
Q

What are the 7 main parts of the basal ganglia?

A
Putamen
Subthalamic nucleus
Substantia nigra
Hypothalamus
Globus pallidus (madia &amp; lateral)
Thalamus
Caudate nucleus
89
Q

What does the striatum do?

A

Caudate & putamen
Main target input of basal ganglia
Releases GABA
Inhibitory (rostral)

90
Q

What is the lentiform nucleus made up of?

A

Globus pallidus & putamen

91
Q

What does the globus pallid us do?

A

Output source to thalamus

92
Q

What does the subthalamic nucleus do?

A

Communicates with globus pallidus

Caudal

93
Q

What does the substantia nigra do?

A

In tegmenjtum
Releases dopamine
Caudal (excitatory)

94
Q

What are the 7 main parts of the limbic system?

A
Cingulate gyrus
Thalamus
Fornix
Hypothalamus
Mamillary body
Hippocampus
Amgdala
95
Q

What is the Papez circuit?

A

Neural circuit for the control of emotional expression

96
Q

What are the components of the Papez circuit?

A

Hippocampal formation → fornix → mammillary bodies → anterior thalamic nucleus → cingulum → hippocampal formation

97
Q

What is the fornix?

A

Pathway of nerve fibres that transmit information from hippocampus to mamillary body

98
Q

What is the role of the hippocampus?

A

Involved in learning, memory & recollection of spatial relationships

99
Q

What is the role of the parahippocampal gyrus?

A

Helps modify expression of emotions

100
Q

What is the role of the amygdala?

A

Influences behaviour & fear

101
Q

What is the mamillary body?

A

Tiny nucleus acting a a relay station of information from the fornix to the thalamus

102
Q

What are the 4 cerebellar nuclei?

A

Dentate
Emboliform
Globose
Fastigi

103
Q

What is the role of the cerebellum?

A

Coordinates voluntary movement
Balance
Equilibrium
Muscle tone

104
Q

What connects the cerebellum to the midbrain?

A

Peduncles

105
Q

What are the 3 lobes of the cerebellum?

A

Anterior
Posterior
Floculonodular

106
Q

What are the fissures of the cerebellum?

A

Primary - between anterior & posterior
Horizontal - makes lateral & posterior margins of hemisphere
Posterolateral - between floculonodular & posterior

107
Q

What joins the hemispheres of the cerebellum at the midline?

A

Vermis

108
Q

What are the functional divisions of the cerebellum?

A

Cerebrocerebellum (neocerebellum
Spinocerebellum (paleocerebellum)
Vestibulocerebellum (archicerebellum)

109
Q

What does the cerebrocerebellum do, is made up of & inputs from?

A

Planning movements, motor learning, trajectory
Lateral hemispheres
Input from pons via peduncle

110
Q

What does the spinocerebellum do, is made up of & inputs from?

A

Regulating body movement, muscle tone, posture
Vermis
Spinocerebellar tracts via peduncles

111
Q

What does the vestibulocerebellum do, is made up of & inputs from?

A

Controlling balance & ocular reflexes
Flocculonodular lobe & fastigi nuclei
Input from vestibular nuclei via peduncles

112
Q

What are the 3 arteries that supply the cerebellum?

A

Superior cerebellar
Anterior inferior cerebellar
Posterior inferior cerebellar

113
Q

What are the 3 peduncles?

A

Superior - midbrain
Middle - pons
Inferior - medulla

114
Q

What are the 3 layers of the cerebellar cortex from superficial to deep?

A

Molecular
Purkinje
Granule

115
Q

What are the 2 inputs to the cerebellar cortex?

A

Mossy fibres - from middle peduncle, inform of voluntary motor input, synapse with granule cells, have parallel fibres
Climbing fibres - from inferior peduncle, convey muscle proprioception & vestibular inputs

116
Q

What is the output from the cerebellar cortex?

A

Purkinje cell axons - from dentate nucleus > superior peduncle > thalamus

117
Q

What are the symptoms for cerebellar damage?

A
'DANISH'
Dysmetria (inability to judge distance)
Ataxia (staggering)
Nystagmus (abnormal eye movements)
Intention tremor
Slurred speech
Hypotonia (weak muscles)
118
Q

What are the 3 primary brain vesicles?

A

Prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)

119
Q

What are the 5 secondary brain vesicles?

A

Pros -> telencephalon & diencephalon
Mes -> mesencephalon
Rhomb -> metencephalon & myelencephalon

120
Q

What do each of the primary brain vesicles from?

A

Pros - cerebrum; thalamus
Mes - midbrain
Rhomb - cerebellum & pons; medulla