Building Brains 3 Flashcards
(166 cards)
1
Q
How does the brainstem play a role in endocrine function? (1)
A
Via stimulation of the hypothalamus
2
Q
How does the brainstem play a role in consciousness, alertness, and sleep? (1)
A
Via the ascending reticular activating system
3
Q
Give two inputs to the inferior colliculi. (2)
A
- Cochlea
- Brainstem nuclei
4
Q
Give two outputs of the inferior colliculi. (2)
A
- Medial geniculate bodies
- Auditory cortex
5
Q
Give two functions of the inferior colliculi. (2)
A
- Relays auditory information
- Localises sound
6
Q
Give two inputs to the superior colliculi. (2)
A
- Retina
- Visual cortex
7
Q
Give two outputs of the superior colliculi. (2)
A
- Tectospinal tract
- Brainstem
8
Q
What is the function of the superior colliculi? (1)
A
Head and eye tracking movements
9
Q
What is the role of the olives? (1)
A
Input to the cerebellum
10
Q
Give two outputs of the midbrain tegmentum. (2)
A
- Extrapyramidal tracts
- Basal ganglia
11
Q
Describe the reticular formation, including its location. (2)
A
Ill-defined collection of inter-mingled neurones.
It spans the length of the brainstem.
12
Q
What is the role of the reticular formation? (1)
A
Controls consciousness, alertness, and sleep via the ascending reticular activating system.
13
Q
Name the three approximate groups of nuclei in the reticular formation, and their relative locations. (6)
A
- Raphe (median)
- Magnocellular (medial)
- Parvocellular (lateral)
14
Q
Which neurotransmitter do the raphe nuclei of the reticular formation produce? (1)
A
Serotonin
15
Q
What is the function of the tectospinal tract? (1)
A
Head and neck orientation to visual stimuli
16
Q
Describe the lateralisation of the tectospinal tract. (1)
A
Innervates contralaterally
17
Q
Name the original input/s to the tectospinal tract.
A
Visual cortex and retina
18
Q
Where does the tectospinal tract originate? (1)
A
Superior colliculus (midbrain)
19
Q
Where does the tectospinal tract decussate? (1)
A
In midbrain (quickly after it starts)
20
Q
In roughly which area of the brainstem and spinal cord does the tectospinal tract descend? (1)
A
Medially
21
Q
Where does the tectospinal tract terminate? (1)
A
Upper cervical levels of the spinal cord
22
Q
Name cranial nerve I. (1)
A
Olfactory nerve
23
Q
Is cranial nerve I sensory, motor, parasympathetic, or a mix? (1)
A
Sensory
24
Q
What is the role of CNI? (1)
A
Sense of smell
25
Name CNII. (2)
Optic nerve
26
Is CNII sensory, motor, parasympathetic, or a mix? (1)
Sensory
27
What is the role of CNII? (1)
Vision from the retina
28
Name CNIII. (1)
Oculomotor
29
Is CNIII sensory, motor, parasympathetic, or a mix? (1)
Motor and parasympathetic
30
Describe the motor functions of CNIII. (5)
- Medial rectus (eye movements)
- Superior rectus (eye movements)
- Inferior rectus (eye movements)
- Inferior oblique (eye movements)
- Levator palpabrae superioris (lifting eyelid)
31
Describe the parasympathetic function of CNIII. (2)
Pupil constriction
via sphincter pupillae and ciliary muscles
32
Name CNIV. (1)
Trochlear
33
Is CNIV sensory, motor, parasympathetic, or a mix? (1)
Motor
34
What is the function of CNIV? (1)
Rotates eye (superior oblique)
35
Name CNVI. (1)
Abducens
36
Is CNVI sensory, motor, parasympathetic, or a mix? (1)
Motor
37
Give the role of CNVI. (1)
Abducts eye (lateral rectus)
38
Name CNV. (1)
Trigeminal
39
Is CNV sensory, motor, parasympathetic, or a mix? (1)
Sensory and motor
40
What is the sensory function of CNV? (1)
Sensation from face
41
What is the motor function of CNV? (1)
Muscles of mastication
42
Are the cranial nerves considered part of the central or peripheral nervous system? (1)
Peripheral
43
Name CNVII. (1)
Facial
44
Is CNVII sensory, motor, parasympathetic, or a mix? (1)
Sensory, motor, and parasympathetic
45
Give the sensory functions of CNVII. (2)
- Taste from anterior 2/3 of tongue
- Skin behind ear
46
What is the motor function of CNVII? (1)
Muscles of facial expression
47
What is the parasympathetic function of CNVII? (1)
Salivary glands (except parotid)
48
Name CNVIII. (1)
Vestibulocochlear
49
Is CNVIII sensory, motor, parasympathetic, or a mix? (1)
Sensory
50
What is the function of CNVIII? (1)
Hearing and balance
51
Name CNIX. (1)
Glossopharyngeal
52
Is CNIX sensory, motor, parasympathetic, or a mix? (1)
Sensory, motor, and parasympathetic
53
What is the sensory function of CNIX? (1)
Taste from posterior 1/3 of tongue
54
What is the motor function of CNIX? (1)
Pharynx (stylopharyngeus muscle)
55
What is the parasympathetic function of CNIX? (1)
Salivation (parotid gland)
56
Name CNX. (1)
Vagus
57
Is CNX sensory, motor, parasympathetic, or a mix? (1)
Sensory, motor, and parasympathetic
58
What are the sensory functions of CNX? (2)
- Sensation from pharynx and palate
- Taste from epiglottis
59
What is the motor function of CNX? (1)
Soft palate and larynx
60
What is the parasympathetic function of CNX? (1)
Thoracic and abdominal viscera/organs
61
Name CNXI. (1)
Accessory
62
Is CNXI sensory, motor, parasympathetic, or a mix? (1)
Motor
63
What are the functions of CNXI and what muscles does it innervate? (4)
- Turn head (sternocleidomastoid)
- Shrug shoulders (trapezius)
64
Name CNXII. (1)
Hypoglossal
65
Is CNXII sensory, motor, parasympathetic, or a mix? (1)
Motor
66
What is the function of CNXII? (1)
Tongue movements
67
If there was a lesion in CNXII, what clinical sign would be seen? (1)
Tongue deviates towards damaged side
68
Which is the only cranial nerve to originate on the dorsal side of the brainstem? (1)
CNIV
69
Which cranial nerves/parts of cranial nerves does the salivatory nucleus contain? (1)
Parasympathetic parts of:
- Facial CNVII
- Glossopharyngeal IX
70
Which cranial nerves/parts of cranial nerves does the nucleus ambiguus contain? (1)
Motor parts of:
- glossopharyngeal CNIX
- Vagus CNX
71
What is the role of the dorsal motor nucleus in the brainstem? (1)
Parasympathetic nucleus of the vagus nerve
72
Which cranial nerves/parts of cranial nerves does the solitary nucleus contain? (1)
Sensation from:
- Facial VII
- Glossopharyngeal IX
- Vagus X
73
Which cranial nerves/parts of cranial nerves does the spinal trigeminal nucleus contain? (1)
Sensation from:
- Trigeminal V
- Facial VII
- Glossopharyngeal IX
- Vagus X
74
Give three functions of the cerebellum. (3)
- Equilibrium (balance)
- Posture
- Dynamic coordination and synchronisation of muscles
75
Complete the sentence... (2)
The cerebellum stores ............... and compares them with actual movement, then feeds back to the ..................
Motor plans
Cortex
76
Name the three STRUCTURAL divisions of the cerebellum. (3)
- Anterior lobe
- Posterior lobe
- Flocculonodular lobe
77
Which is the largest lobe of the cerebellum? (1)
Posterior lobe
78
Name the fissure of the cerebellum which separates the anterior and posterior lobes. (1)
Primary fissure
79
Name the fissure of the cerebellum which separates the posterior lobe and the flocculonodular lobes. (1)
Posterolateral fissure
80
Name the part of the cerebellum which lies medially and joins the hemispheres. (1)
Vermis
81
Describe the three components of the flocculonodular lobe of the cerebellum. (3)
Nodulus in the middle
Flocculus on either side
82
The superior cerebellar peduncle connects the cerebellum with which part of the brain? (1)
Midbrain
83
The middle cerebellar peduncle connects the cerebellum with which part of the brain? (1)
Pons
84
The inferior cerebellar peduncle connects the cerebellum with which part of the brain? (1)
Medulla
85
Name the three FUNCTIONAL divisions of the cerebellum. (3)
- Vermis/intermediate zone
- Lateral hemispheres
- Flocculonodular lobe
86
What is the role of the deep cerebellar nuclei? (1)
Output pathways of the basal ganglia
87
Name the three deep cerebellar nuclei. (3)
- Fastigial
- Dentate
- Interposed
88
The spinocerebellum is composed of which functional zone of the cerebellum? (1)
Vermis/intermediate zone
89
The cerebrocerebellum is composed of which functional zone of the cerebellum? (1)
Lateral hemispheres
90
The vestibulocerebellum is composed of which functional zone of the cerebellum? (1)
Flocculonodular lobe
91
How many layers of cortex does the cerebellum have? (1)
3
92
Name the cortical layers of the cerebellum from outer to inner. (3)
- Molecular
- Purkinje
- Granular
93
Describe the cells seen in the granular layer of the cerebellar cortex. (1)
Dense granular cells
94
Describe the cells seen in the purkinje layer of the cerebellar cortex. (1)
Single layer of purkinje cells
95
Describe the elements that would be seen in the molecular layer of the cerebellar cortex. (3)
- Interneurones
- Granular axons
- Purkinje dendrites
96
Which layer of the cerebellar cortex receives input? (1)
Granular layer
97
Which layer of the cerebellar cortex gives output, and where to? (2)
Purkinje cells give output to cerebellar nuclei.
98
Describe the axons of granular cells in the molecular layer of the cerebellar cortex. (1)
Parallel fibres
99
Describe a simple typical pathway of input to output in the cerebellum. (5)
Input to granular cells
Axons ascend to molecular layer
Granular axons synapse on purkinje dendrites in molecular layer
Purkinje cells project to deep cerebellar nuclei
Output from cerebellar nuclei
100
Describe the function of mossy cells in the cerebellum. (2)
Carry signals from spinal cord and brainstem
to granular cells.
101
Describe the ratio of mossy fibres : granular cells in the cerebellar cortex. (1)
One mossy fibre : many granular cells
102
Describe the role of climbing fibres in the cerebellum. (2)
Carry signals from olives
to purkinje cells.
103
Describe the ratio of climbing fibres and purkinje cells in the cerebellum. (2)
Each purkinje cell receives input from one climbing fibre.
Each climbing fibre can innervate many purkinje cells.
104
Which deep cerebellar nuclei are most medial? (1)
Fastigial
105
Which deep cerebellar nuclei are the largest? (1)
Dentate
106
Give the input and output of the vestibulocerebellar pathway. (3)
INPUT:
Vestibulocochlear nerve
OUTPUTS:
Vestibulospinal tract
Reticulospinal tract
107
What is the role of the vestibulocerebellar pathway? (2)
Receives proprioceptive information
and mediates posture, balance, and head movements.
108
Describe the vestibulocerebellar pathway. (9)
- Vestibulocochlear nerve
- Vestibulocochlear nuclei
- Vestibulocerebellar fibres
- Granule cells of the flocculonodular lobe
- Purkinje cells
- Fastigial nucleus
- Fastigial fibres
- Reticular formation and vestibulocochlear nuclei
- Vestibulospinal and reticulospinal tracts
109
What is the origin of the vestibulospinal tract? (1)
Vestibulocochlear nuclei
110
Where does the medial vestibulospinal tract decussate? (1)
It doesn't - it descends and innervates bilaterally
111
Where does the medial vestibulospinal tract synapse? (1)
Cervical spinal cord
112
Describe the laterality of the lateral vestibulospinal tract. (1)
Innervates ipsilaterally
113
Where does the lateral vestibulospinal tract synapse? (1)
Along the length of the spinal cord.
114
Which division of the vestibulospinal tract maintains balance and posture via extensor and antigravity muscles? (1)
Lateral
115
Which division of the vestibulospinal tract maintains head and neck position? (1)
Medial
116
Where does the reticulospinal tract originate? (1)
Reticular formation of pons and medulla
117
Describe the laterality of the reticulospinal tract. (1)
Mostly innervates ipsilaterally
118
Where do the medial and lateral reticulospinal tracts synapse? (1)
Throughout the spinal cord
119
What is the role of the reticulospinal tract? (1)
To assist the vestibulospinal tract in controlling extensor muscles.
120
Give the input and output of the cerebrocerebellar pathway. (3)
INPUT
Cortex (via Pontine nuclei)
OUTPUT
Rubrospinal tract
Cortex
121
What is the function of the cerebrocerebellar pathway? (1)
Force, planning and timing of movement
122
Describe the cerebrocerebellar pathway. (9)
- Corticopontine fibres
- Pontine nuclei
- Pontocerebellar fibres
- Granule cells of lateral hemisphere
- Purkinje cells
- Dentate nucleus
- Dentatorubrothalamic fibres
- Red nucleus and thalamus
- Rubrospinal tract and thalamocortical fibres
123
Where does the rubrospinal tract originate? (1)
Red nucleus (midbrain)
124
Where does the rubrospinal tract decussate? (1)
Midbrain (decussates quickly after origin)
125
In which area of the brainstem/spinalcord does the rubrospinal tract descend? (1)
Laterally, alongside corticospinal tract
126
Describe the laterality of the rubrospinal tract. (1)
Innervates contralaterally
127
Describe the function of the rubrospinal tract and how it carries out its function. (2)
- Assists corticospinal tract by adjusting flexor muscles (primarily of upper limbs)
- Does this by receiving collaterals from the corticospinal tract
128
Give the input and output of the spinocerebellar pathway. (2)
INPUT
spinocerebellar tracts
OUTPUT
rubrospinal tract
cortex
129
What is the function of the spinocerebellar tract? (1)
Coordination of limb movement and gait
130
Describe the spinocerebellar Pathway. (9)
- Sensory neurones
- Dorsal horn
- Spinocerebellar tracts (mossy fibres)
- Granule cells of the vermis and intermediate zones
- Purkinje cells
- Interposed nuclei
- Interpositionorubrothalamic fibres
- Thalamus and red nucleus
- Cortex and rubrospinal tract
131
There are two divisions of the spinocerebellar tract (ventral and dorsal).
The ventral spinocerebellar tract communicates with the cerebellum via which peduncle? (1)
Superior cerebellar peduncle
132
There are two divisions of the spinocerebellar tract (ventral and dorsal).
The dorsal spinocerebellar tract communicates with the cerebellum via which peduncle? (1)
Inferior cerebellar peduncle
133
Which of the three cerebellar pathways use mossy fibres?
Spinocerebellum
134
The spinothalamic tract conveys information from which type/s of sensory fibres?
A delta and C
135
Which sensory modalities does the DCML pathway convey? (3)
- Fine touch
- Vibration
- Proprioception
136
Name the two fasciculi which together make up the dorsal columns. (1)
- Fasciculus cuneatus
- Fasciculus gracilis
137
Are the neurones which make up the dorsal columns first, second, or third order neurones? (1)
First
138
Describe the relative location of the fasciculus cuneatus. (1)
Lateral
139
Does the fasciculus cuneatus carry signals from the upper or lower limbs? (1)
Upper
140
Describe the relative location of the fasciculus gracilis. (1)
Medial
141
Does the fasciculus gracilis carry signals from the upper or lower limbs? (1)
Lower
142
Where do the first order neurones of the DCML pathway first synapse? (1)
Nucleus cuneatus or nucleus gracilis of the medulla.
143
Where does the DCML pathway decussate? (1)
Medulla (just after synapsing)
144
Where does the DCML pathway project to after synapsing in the medulla, and how does it get there? (2)
Projects to thalamus
via the medial lemnisci.
145
Where does the DCML pathway end? (1)
Primary somatosensory cortex
146
Name two mechanoreceptors which are located towards the surface of the skin. (2)
Merkel's disks
Meissner's corpuscles
147
Name two mechanoreceptors which are located deep in the dermis. (2)
Pacinian corpuscles
Ruffini's endings
148
Which type of mechanoreceptor is responsible for detecting pain? (1)
Free nerve endings
149
What sensory modality do Ruffini's endings detect? (1)
Stretching of the skin
150
What sensory modalities do Meissner's corpuscles detect? (2)
Touch
Pressure
151
What sensory modalities do Pacinian corpuscles detect? (2)
Deep pressure
Vibration
152
Which sensory modalities do Merkel's disks detect? (2)
Touch
Pressure
153
Ruffini's endings, Pacinian corpuscles, Merkel's disks, and Meissner's corpuscles all send information to the spinal cord via which type of sensory fibre? (1)
A beta
154
Complete the sentence... (1)
Adaptation describes a mechanoreceptor's response to ...........................
An ongoing stimulus
155
Give two mechanoreceptors which have small receptive fields. (2)
Meissner's corpuscles
Merkel's disks
156
Give two mechanoreceptors which have large receptive fields. (2)
Pacinian corpuscle
Ruffini's ending
157
Name two mechanoreceptors which are rapidly adapting. (2)
Meissner's corpuscle
Pacinian corpuscle
158
Name two mechanoreceptors which are slowly adapting. (2)
Merkel's disk
Ruffini's ending
159
Describe the firing pattern of rapidly adapting mechanoreceptors. (1)
Stop firing quickly after stimulus onset
160
Describe the firing pattern of slowly adapting mechanoreceptors. (1)
Continue firing for a period after stimulus onset
161
Give the three types of nociceptor and the sensory fibres that they are associated with. (6)
Thermal - A delta fibres
Mechanical - A delta fibres
Polymodal - C fibres
162
What types of stimulus can activate polymodal nociceptors? (3)
Mechanical
Thermal
Chemical
163
Nociceptors are activated by which type of ion channels? (1)
TRP (transient receptor potential) channels
164
How do TRP channels lead to nociceptor activation? (1)
Influx of calcium
165
Give four inputs to the brainstem which may trigger vomiting. (4)
- Cerebral cortex
- Vestibular system
- Blood toxins
- Stomach / GI system
166
Give six areas of the brainstem which are involved in vomiting. (6)
- Area postrema
- Respiratory groups
- Dorsal motor nuclei
- Vomiting centre
- Solitary nucleus
- Salivatory nucleus
