Neuro Flashcards

1
Q

What is sound?

A

Displacement of air particles following a sinusoidal pattern of compression and rarefaction.

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

What is the range of hearing for humans?

A

20Hz -> 20kHz.

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

What are the four components of the auditory system?

A
  • The outer ear.
  • The middle ear.
  • The inner ear.
  • Central auditory pathways.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does the outer ear consist of?

A
  • Pinna.
  • Ear canal.
  • Tympanic memebrane.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of the pinna?

A
  • Shaped to gather sound waves and direct them into the ear canal.
  • Filters out lower frequency sounds.
  • Each pinna is unique.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the function of the ear canal?

A

Directs sound waves towards the tympanic membrane.

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

What happens when sound hits the tympanic membrane?

A

It vibrates like the surface of a drum and transmits the sound waves deeper into the ear towards the cochlea.

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

What does the middle ear consist of?

A
  • The ossicles.
  • The Eustachian tube.
  • Tensor tympani and stapedius muscles.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the ossicles and how they function.

A
  • Malleus (hammer): rests against tympanic membrane, head of the ‘hammer’ connects to incus.
  • Incus (anvil): when struck by ‘hammer’ sound waves are transmitted to the stapes.
  • Stapes (stirrups): receives sound waves, transmitting them to oval window.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Discuss the importance of the superior and inferior openings of the auditory tube.

A
  • Superior: middle ear cavity.
  • Inferior: nasal cavity.
  • Therefore, connection of airflow from external environment and middle ear.
  • Vital for maintaining equal air pressure either side of the tympanic membrane, preventing pain and rupture.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the main role of the tensor tympani and stapedius muscles?

A

To dampen sound vibrations and reduce perceived volume.

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

What does the inner ear consist of?

A
  • The cochlea.
  • The vestibular system.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the cochlea allow us to perceive?

A

Sound.

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

What does the vestibular system consist of?

A
  • Semicircular canaks.
  • Utricle.
  • Saccule.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the vestibular system allow us to perceive? Which structures within it allow these perceptions?

A

Movement - semicircular canals.
Linear acceleration - utricle and saccule.

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

What are the 2 openings of the cochlea?

A

Round window and oval window.

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

What are the 3 components of the cochlea?

A
  • Scala vestibuli.
  • Scala media.
  • Scala tympani.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which ionic fluid is found in the scala media?

A

Perilymph, high in K+.

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

Which ionic fluid is found in the scala vestibuli and scala tympani?

A

Endolymph, rich in Na+.

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

What affect on hearing can ion channel abnormalities have?

A

Can cause deafness.

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

Describe the basilar membrane.

A
  • Narrow and stiff at base.
  • Wide and floppy at apex.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is tonotopy and which membrane has this feature?

A
  • The organisation of sound frequencies along an axis.
  • Basilar membrane.
  • High frequencies detected at base.
  • Low frequencies detected at apex.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is the organ of Corti?

A

In the scala media.

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

Are the basilar and tectorial membranes mobile or fixed in place?

A

Basilar - mobile.
Tectorial - fixed.

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

Discuss the importance and basic roles of the hair cells of the organ of Corti.

A

Inner hair cells - important, mechanical transduction.
Outer hair cells - helpful, fine tuning.

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

How do the inner hair cells perform mechanical transfuction?

A

Basilar membrane moves -> inner hair cells move -> activate attached cochlear nerve fibres -> cochlear nerve -> activated central auditory pathway.

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

What will occur upon loss of inner hair cells?

A

Deafness.

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

How do the outer hair cells fine tune sound?

A

Stiffen basilar membrane either side of the maximum stimulated inner hair cells, to focus on that sound and dampen others.

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

What will occur upon loss of outer hair cells?

A

Loss of sharpness of hearing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is interaural time difference?

A

One ear hearing a sound first, as that ear is closer to the sound.

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

What is interaural intensity difference?

A

One ear hearing a sound louder, as that ear is closer to the sound.

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

What type of hearing loss occurs with a defective outer/middle ear?

A

Conductive hearing loss.

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

What type of hearing loss occurs with a defective inner ear?

A

Sensorineural hearing loss.

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

What are neurons specialised for?

A

Electrical signalling.

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

When are neurons mainly formed?

A

During development, but small areas of the brain may continue making neurons e..g the hippocampus.

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

Which are formed first; neurons or glia?

A

Neurons.

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

What are the two forms of neuronal synapse?

A

Chemical and electrical.

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

How do chemical synapses work? Give an example.

A

Via neurotransmitters e.g. glutamate.

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

How do electrical synapses work? Give an example.

A

Via a direct flow of ions e.g. hypothalamus for hormone secretion.

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

Define neural plasticity.

A

Changes in neuronal/synaptic structure and function in response to neural activity. It is the basis of learning and memory.

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

Give an example of neuronal heterogenity.

A

Neocortex. 6 layers of varying cells/structures.

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

What is the key role of oligodendrocytes?

A

Myelinating cells of the CNS.

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

Describe the role of myelin.

A

Insulates axon segments, enabling rapid nerve conduction.

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

Describe the structure of the myelin sheaths.

A

Interrupted by nodes of Ranvier, to allow saltatory conduction (faster).

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

Describe microglia.

A

Resident immune cells of the CNS. Phagocytic.

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

Describe the origin of microglia.

A

Originate from yolk sac progenitors that migrate into the CNS, therefore closer to macrophages in origin.

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

Describe the varying structure of microglia in different states.

A

Resting state - highly ramified.
Activated - retract processes, become amoeboid.

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

Give 3 functions of microglia.

A
  • Immune surveillance.
  • Phagocytosis.
  • Synaptic plasticity.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Describe astrocytes.

A

Star-like cells, most numerous glial cells in the CNS, highly heterogenous.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Give 5 functions of astrocytes.

A
  • Define brain micro-architecture.
  • Envelope / tripartite synapses, buffer K+ etc.
  • Metabolic support.
  • Neurovascular coupling.
  • Proliferate in disease.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Name 3 specialised astrocytes.

A
  • Radial glia.
  • Bergmann glia.
  • Müller cells.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What are radial glia important for?

A

Brain development.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What are Bergmann glia important for?

A

Structure (cerebellum).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What are Müller cells important for?

A

Providing a scaffold for other cells to form on (retina).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Define motor neurone disease.

A

Adult-onset neurodegenerative disease, characterised by loss of upper and lower motor neurones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Define multiple sclerosis.

A

Autoimmune demyelinating disease, where immune cells attack the myelin sheath of oligodendrocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Give the 4 features of the blood-brain barrier.

A
  • Endothelial cell tight junctions.
  • Basement membrane.
  • Astrocyte end feet.
  • Pericytes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Give 4 events that the blood-brain barrier is sensitive to.

A
  • Inflammation.
  • Hypertension.
  • Trauma.
  • Ischaemia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Where can ependymal cells be found?

A

Lining ventricles and the central canal of the spinal cord.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the function of ependymal cells?

A
  • CSF production, flow and absorption.
  • Allowing solute exchange between nervous tissue and CSF.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Describe the structure of ependymal cells.

A
  • Epithelial-like.
  • Ciliated to facilitate flow,.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is the main site of CSF production?

A

Choroid plexus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

How is the choroid plexus formed?

A

From modified ependymal cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What does the term myoclonus refer to? Give an example of a form of myoclonus.

A
  • A quick jerking movement that you cannot control.
  • E.g. the hiccups.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Describe the McGurk Effect.

A

Occurs when the auditory component of one sound is paired with the visual component of another sound, leading to the perception of a third sound.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What % of your brain is far?

A

60%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What % are the neocortex and language centres of your brain?

A

76%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What are the primitive reflexes?

A

The reflex actions arising from the brainstem that are typically present in childhood, but not in healthy or neurological intact adults, in response to particular stimuli.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is the rooting reflex?

A

Turn head and mouth in direction of stroking of cheek.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What is the sucking reflex?

A

Sucking objects that touch the lips.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What is the moro (startle) reflex?

A

Back arches, legs and arms flung out and then brought back towards chest in hugging motion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What is the grasping (palmar) reflex?

A

Grasping objects pressed against palms.

73
Q

What is the stepping reflex?

A

Mimicking walking when held upright.

74
Q

What is the babinski reflex?

A

Fanning toes when feet are stroked.

75
Q

What is the tonic-neck reflex?

A

Turning head to one side, extending arm and leg.

76
Q

How long are infants usually ambidextrous?

A

Until 3 years old.

77
Q

Define anencephaly.

A

A serious birth defect in which a baby is born without parts of the brain and skull, a form of NTD.

78
Q

Define lishencephaly.

A

A smooth brain, a neuronal migration disorder.

79
Q

Describe cystic periventricular leukomalacia and its rarity.

A
  • Death of oligodendrocytes -> virtually no plasticity,
  • Around 5% of babies less than 32 weeks.
80
Q

What can mutations of the PHOX2B gene affect?

A

The development of the key structures that regulate chemical control of breathing.

81
Q

Give 5 things neural crest cells form.

A
  • Sensory ganglia.
  • Schwann cells.
  • Adrenal medulla.
  • Meninges.
  • Dermis.
82
Q

Where can the tectum be found?

A

A region of the midbrain posterior to the cerebral aqueduct of Sylvius.

83
Q

What does the tectum contain, and what are these involved in?

A
  • Nuclei of the superior and inferior colliculi.
  • Colliculi process stimuli before they reach their corresponding primary processing centres.
  • Superior = visual stimuli.
  • Inferior = auditory stimuli.
84
Q

Where can the tegmentum be found?

A

Between the cerebral aqueduct and the pars compacta of the substantia nigra.

85
Q

What are the names of the two areas of the tegmentum named after colours?

A
  • The red nucleus.
  • The periaqueductal grey.
86
Q

Describe the substantia nigra.

A
  • Part of basal ganglia.
  • Two parts: pars compacta and pars reticular.
  • Pars compacta = basal ganglia input.
  • Pars reticular = basal ganglia output.
87
Q

What is the red nucleus involved in?

A

The co-ordination of movements.

88
Q

What is the periaqueductal grey involved in?

A

Pain processing.

89
Q

What is the limbic system made up of (not inclusive)?

A
  • Amygdala.
  • Hippocampus.
  • Fornix.
  • Cingulate gyrus.
  • Septum.
  • Mammillary body.
  • Hypothalamus.
  • Thalamus.
90
Q

What is the limbic system involved in?

A
  • Emotion.
  • Motivation.
  • Emotional associations within memory.
91
Q

Define a neuron.

A

The basic cellular unit of the nervous system.

92
Q

How many neurons are there in the average human brain?

A

~ 100 billion.

93
Q

How many synapses are there in the average human brain?

A

~ 150 trillion.

94
Q

Although neurons can be specialised, which 4 basic components do they all have?

A
  • Dendrites.
  • Cell body.
  • Axon.
  • Presynaptic terminals.
95
Q

Define axonal transmission.

A

Transmission of information from location A to location B.

96
Q

Define synaptic transmission.

A

Integration/processing of information and transmission between neurons.

97
Q

At rest, describe the neuron’s electric charge? Why is it this way?

A
  • Negative ~ -70mV.
  • Large organic proteins are the reason.
98
Q

Describe the permeability of the neuronal cell membrane. Give some examples of what can/cannot pass through.

A
  • Semi-permeable.
  • K+ and Cl- cross readily.
  • Na+ cross with difficulty.
99
Q

What are the 2 forces determining the distribution of charged ions?

A
  • Diffusion.
  • Electrostatic attraction/repulsion.
100
Q

Describe the locations of these ions at rest:
- Anions (proteins)
- Na+
- K+
- Cl-

A
  • Anions (proteins) = restricted to inside of cell.
  • Na+ = mostly outside cell.
  • K+ = mostly inside cell.
  • Cl- = mostly outside cell.
101
Q

Describe the sodium-potassium pump of a neuron.

A
  • Transports Na+ out of neuron.
  • Transports K+ into neuron.
  • 3 Na+ out for every 2 K+ in.
  • Requires energy supplied by ATP.
102
Q

What do excitatory neurotransmitters do to the cell membrane?

A
  • Depolarise it.
  • Increasing the chance of an action potential.
  • Causes an excitatory post synaptic potential (EPSP).
103
Q

What do inhibitory neurotransmitters do to the cell membrane?

A
  • Hyperpolarise it.
  • Decreasing probability of an action potential being generated.
  • Causes an inhibitory post synaptic potential (IPSP).
104
Q

Explain the generation of an action potential via EPSPs.

A

Will only be generated if the membrane potential is depolarised beyond the threshold of excitation, which may take multiple triggers to create a big enough EPSP).

105
Q

What is the excitation threshold for an action potential to be generated?

A

~ - 60mV.

106
Q

Give 7 symptoms of multiple sclerosis.

A
  • Uncontrolled eye movements/seeing double.
  • Slurred speech.
  • Partial/complete paralysis.
  • Tremor.
  • Loss of co-ordination.
  • Weakness/fatigue.
  • Numbness/prickling/pain.
107
Q

Which groups of people get multiple sclerosis?

A
  • Young adults (20 -> 40).
  • Slightly more women then men.
108
Q

What is the affect of Novichok?

A
  • Disrupts synaptic neurotransmission for ACh, as it is an AChE inhibitor (stops breakdown of acetylcholine).
109
Q

How can the effects of Novichok be treated?

A

By using atropine (an ACh receptor blocker.

110
Q

What 2 processes prevent neurotransmitters remaining active in a synapse?

A
  • Enzymatic degradation.
  • Re-uptake.
111
Q

What does acetylcholine do?

A
  • It is a key neurotransmitter at the neuromuscular junction.
  • Activates muscles, not just skeletal for voluntary, but also the heart, respiratory muscles, GI tract, eye muscles, and muscles around blood vessels.
112
Q

What are the 5 fundamental processes of synaptic tranmission?

A
  1. Manufacture.
  2. Storage.
  3. Release.
  4. Interact with post-synaptic receptors.
  5. Inactivation.
113
Q

Name 3 ‘fast’ neurotransmitters.

A
  • Acetylcholine.
  • Glutamate.
  • Gamma-aminobutyric acid.
114
Q

Name 3 neuromodulators.

A
  • Dopamine.
  • Noradrenaline.
  • Serotonin.
115
Q

Name 4 things that can affect acetylcholine, and how they affect it.

A
  • Cigarettes (agonist).
  • Poison arrows (antagonist).
  • Spider toxins (release.
  • Nerve gas (blocks break down).
116
Q

What is gamma-aminobutyric acid?

A

The main inhibitory neurotransmitter.

117
Q

Name 3 things that affect gamma-aminobutyric acid, and how they affect it.

A
  • Anti-anxiety drugs (inhibit receptors).
  • Anticonvulsant drugs (inhibit receptors).
  • Anaesthetics (potentiate the effects).
118
Q

Name 3 things that affect dopamine, and how they affect it.

A
  • Antipsychotic drugs (block receptors).
  • Stimulants (increase release, block re-uptake).
  • Anti-Parkinson drugs (increases manufacture).
119
Q

Name 2 things that affect noradrenaline, and how they affect it.

A
  • Antidepressants (block re-uptake and block breakdown).
  • Stimulants (increases release and blocks re-uptake).
120
Q

Name 3 things that affect serotonin, and how they affect it.

A
  • Antidepressants (SSRI = re-uptake inhibitor).
  • Hallucinogens (receptor agonist).
  • Ecstasy (increases release, reduces re-uptake).
121
Q

What are 2 problems for drug design regarding neurotransmitters?

A
  • A region of the brain engaged in a particular function uses several neurotransmission systems.
  • Regions of the brain engaged in different function use the same neurotransmission systems.
122
Q

What are the 4 types of motor control?

A
  • Voluntary.
  • Goal-directed.
  • Habit.
  • Involuntary.
123
Q

In what manner to individual muscles fibres act?

A

In an ‘all or none’ way.

124
Q

What % of body weight does muscle take up?

A

~ 40%.

125
Q

What is the smallest muscle in the body?

A

Stapedius.

126
Q

What is the largest muscle in the body?

A

Gluteus maximus.

127
Q

What is the strongest muscle in the body?

A

Masseter.

128
Q

How does the number of muscle fibres an individual has vary?

A

Appears genetically determined, very little change with time or training.

129
Q

Describe the composition of a skeletal muscle.

A
  • Attached to a bone by a tendon.
  • Comprises several muscle fasciculi.
  • Each muscle fasciculus comprises several muscle fibres.
  • Each muscle fibres comprises of several myofibrils.
  • Myofibrils contain actin and myosin protein filaments.
130
Q

How do muscles contract?

A

When muscle fibre is depolarised, actin and myosin slide past each other - producing muscle contraction.

131
Q

Define a motor unit.

A

A single alpha motor neuron and all the muscle fibres it innervates.

132
Q

How many muscle fibres are innervated by a motor neuron?

A

Different motor neurons innervate different numbers of muscle fibres.

133
Q

What is possible when motor neurons innervate fewer muscle fibres? Give 2 examples.

A

Fewer fibres = greater movement resolution.
E.g. finger tips and tongue.

134
Q

What does activation of an alpha motor neuron cause?

A

Depolarisation, contraction of all muscle fibres in that motor unit.

135
Q

What 2 things does the CNS need to know about muscles to be a good control system?

A
  • How much tension is on the muscle.
  • What is the length/stretch of the muscle.
136
Q

What senses tension on a muscle?

A

Golgi tendon organs.

137
Q

Under conditions of extreme tension, what can golgi tendon organs do?

A

Inhibit muscle fibres, via a circuit in the spinal cord, to prevent damage.

138
Q

What senses stretch of a muscle?

A

Muscle spindles.

139
Q

Describe muscle spindles.

A
  • Muscle sensory receptors.
    -Embedded within most muscles.
  • Composed of intrafusal fibres with sensory fibres coiled around them.
140
Q

How are intrafusal fibres innervated?

A

Separately to extrafusal, by gamma motor neurons.

141
Q

What is the simplest reflex?

A

The stress reflex.

142
Q

Why do cats always land on their feet?

A

The vestibular righting reflex.

143
Q

What does the “Myosin Cross-Bridge Cycle’ require?

A
  • ATP.
  • Calcium ions.
  • Magnesium ions.
144
Q

Which neurotransmitter triggers the Myosin Cross-Bridge cycle?

A

Acetylcholine.

145
Q

Why does rigor mortis occur?

A

As ATP is required for the Myosin Cross-Bridge cycle, and ATP is produced by oxidative metabolism - which stops after death -> muscle contraction and stiffness = rigor mortis.

146
Q

Discuss slow vs fast twitch muscle fibres, and fatigue.

A

Slow = fatigue resistant.
Some fast = fatigue after a while.
Some fast = fatigue rapidly.

147
Q

Where does motor command originate?

A

In motor cortex pyramidal cells (upper motor neurones).

148
Q

How accurate is the homoculus?

A
  • Oversimplification.
  • In reality, more complex and overlapping.
  • Few motor commands require isolated activation of a single motor unit.
149
Q

What 2 routes do the dorsolateral tracts contain?

A
  • A direct corticospinal route.
  • An indirect corticorubrospinal route.
150
Q

What does the indirect dorsolateral tract route (corticorubrospinal) go via?

A

The red nucleus.

151
Q

Which side do dorsolateral tracts innervate?

A

The contralateral side of one segment of the spinal cord.

152
Q

Which muscles do the dorsolateral tracts project to?

A

Distal muscles e.g. fingers.

153
Q

What 2 routes do the ventromedial tracts contain?

A
  • A direct corticospinal route.
  • An indirect cortico-brainstem-spinal tract.
154
Q

What does the indirect ventromedial tract route (cortico-brainstem-spinal) go via?

A
  • Tectum.
  • Vestibular nuclei.
  • Reticular formation.
  • Cranial nerve nuclei.
155
Q

What % of the total brain weight does the cerebellum make up?

A

10%.

156
Q

DISINHIBITORY PATHWAY

A
157
Q

What is the autonomic nervous system divided into?

A

Parasympathetic and sympathetic.

158
Q

In terms of male sexual function, explain which acts are parasympathetic vs sympathetic.

A

Parasympathetic = erection.
Sympathetic = ejaculation.

159
Q

What are the 3 forms of output for the autonomic nervous system?

A
  • Parasympathetic.
  • Sympathetic.
  • Enteric NS.
160
Q

Which type of receptor would be present in the sympathetic system opposed to the parasympathetic system?

A

Adrenergic receptor.

161
Q

Which type of receptor would be present in the parasympathetic system opposed to the sympathetic system?

A

Muscarinic receptor.

162
Q

Which type of receptor would be present in both parasympathetic and sympathetic systems?

A

Nicotinic receptors.

163
Q

Name an input of the autonomic nervous system.

A

The carotid baroreceptors.

164
Q

How are ANS disorders divided?

A

Primary and secondary ANS disorders.

165
Q

Give an example of a primary ANS disorder.

A
  • Multiple system atrophy (Shy-Drager syndrome).
  • Autonomic failure with Parkinson’s disease.
166
Q

Give an example of a secondary ANS disorder.

A
  • Diabetes mellitus.
  • Chronic renal failure.
  • Chronic liver disease.
  • Guillain-Barre syndrome.
  • Tetanus.
  • HIV.
  • Brain tumours.
167
Q

What is the easiest way of measuring ANS function?

A

Cardiovascularly:
- Heart rate and blood pressure beat-by-beat.
- Head-up tilt test.
- Baro-reflex testing (phenylephrine test).

168
Q

Give 5 non-cardiovascular ways to measure ANS function.

A
  • Pupillometry.
  • Sweat measurement.
  • Skin blood flow (thermoregulation).
  • Gastric acid secretion.
  • Sexual function.
169
Q

What 3 groups of disorders may be associated with basal ganglia dysfunction?

A
  • Motor disorders.
  • Psychiatric disorders.
  • Secondary damage.
170
Q

Give 4 motor disorders associated with basal ganglia dysfunction.

A
  • Parkinson’s disease.
  • Huntington’s disease
  • Dystonia.
  • Gilles de la Tourette syndrome.
171
Q

Give 2 psychiatric disorders associated with basal ganglia dysfunction.

A
  • Obsessive compulsive disorder.
  • Attention deficit hyperactivity disorder.
172
Q

Give 2 forms of secondary damage associated with basal ganglia dysfunction.

A
  • Cerebral palsy.
  • Wilson disease.
173
Q

How many dopamine receptors are there? How many classes are there?

A

5:
- D1 - D5.
2:
- D1 = D1 and D5.
- D2 = D2, D3, and D4.

174
Q

Describe the pathway to dopamine.

A

L-Tyrosine -> L-DOPA -> Dopamine.

175
Q

Describe Parkinson’s disease in terms of muscle tone, movement and dopamine.

A
  • Increased muscle tone.
  • Reduced movements.
  • Not enough dopamine.
176
Q

Describe Huntington’s disease in terms of muscle tone, movement and dopamine.

A
  • Decreased muscle tone.
  • Overshooting movements.
  • Too much dopamine.
177
Q

Give 3 key features of Parkinson’s disease.

A
  • Brady/akinesia.
  • Tremor.
  • Rigidity.
178
Q

Give 3 key features of Huntington’s disease.

A
  • Chorea.
  • Dementia/psychiatric illness.
  • Personality change.