Anatomy Of The Brain Flashcards
(162 cards)
1
Q
A sheet of dura mater, lies in the sagittal plane between the two cerebral hemispheres.
A
The falx cerebri
2
Q
Its free border lies above the corpus callosum.
A
The falx cerebri
3
Q
Oriented horizontally, lying beneath the occipital lobes and above the cerebellum.
A
The tentorium cerebelli
4
Q
Translucent, collagenous membrane envelopes the brain and spinal cord.
A
The arachnoid mater
5
Q
A space in which the CSF circulates in.
A
The subarachnoid space
6
Q
What is the blood supply of the brain?
A
Internal carotid + vertebral arteries
7
Q
What is the blood supply of the spinal cord?
A
Vertebral arteries + Radicular arteries derived from the segmental vessels
8
Q
What forms the circle of Willis?
A
Internal carotid + Vertebral arteries
9
Q
One of the most significant arteries supplying the meninges.
A
The middle meningeal artery
10
Q
How many pairs of spinal nerves there are?
A
31 pairs of spinal nerves
11
Q
At which level of the vertebral column does the spinal cord ends?
A
At the level of the intervertebral disc between L1 and L2
12
Q
Which horn is the site of termination of many afferent neurons, conveying sensory impulses to the brain?
A
The dorsal horn
13
Q
Contains motor neurons that innervate skeletal muscles.
A
The ventral horn
14
Q
Which horn contains preganglionic neurons belonging to the sympathetic division of the autonomic nervous system?
A
The lateral horn ( found only in thoracic and upper lumbar levels )
15
Q
A patient complains of loss of sensation of the fine touch, in which tract is the lesion?
A
The dorsal columns
16
Q
During a neurological examination of a patient, you noticed a loss of pain sensation. In which tract the lesion might be?
A
The spinothalamic tract
17
Q
Which tract Carries information from muscle and joint receptors to the cerebellum?
A
The spinocerebellar tracts
18
Q
Which tract controls skilled voluntary movements?
A
Lateral corticospinal tracts ( descending tracts )
19
Q
The two cerebral hemispheres are incompletely separated by.
A
The great longitudinal fissure
20
Q
Contains commissural fibers that unite corresponding regions of the two hemispheres.
A
The corpus callosum
21
Q
Normally lies between the cerebellum and the occipital lobes.
A
The tentorium cerebelli
22
Q
A depression on the dorsal surface of the medulla and pons, beneath the cerebellum.
A
The fourth ventricle
23
Q
Formed by the convergence of the fourth ventricles’ walls.
A
The cerebral aqueduct
24
Q
Formed from the aqueduct, at the junction of midbrain and forebrain.
A
The third ventricle
25
The lateral walls of this ventricle formed by the thalamus and the hypothalamus.
The third ventricle
26
What is the function of the inter-ventricular foramen ( foramen of Monro )?
Connecting the third ventricle to the lateral ventricle
27
What secretes the CSF in the ventricular system?
The choroid plexus
28
What does the brainstem consist of?
The medulla oblongata, pons and midbrain
29
Has centers that control breathing, circulation of blood and the level of consciousness.
The brainstem
30
What is the site of termination of sensory fibers and the origin of motor fibers that run in the cranial nerves?
The cranial nerve nuclei ( in the brainstem )
31
What attaches the cerebellum to the brainstem?
The inferior, middle and superior peduncles
32
What part of the brain concerned with coordination of movement and it operates at an entirely unconscious level?
The cerebellum
33
What does the forebrain consist of?
The diencephalon + The cerebral hemispheres
34
The two sides of the diencephalon are separated by.
The lumen of the third ventricle
35
What are the four main divisions of the diencephalon?
The epithalamus, thalamus, subthalamus and hypothalamus
36
Where does the pineal gland located on?
On the epithalamus
37
What is the largest part of the diencephalon?
The thalamus
38
Forms much of the lateral wall of the third ventricle.
The thalamus
39
Forms the lower part of the walls and the floor of the third ventricle.
The hypothalamus
40
A continuous furrow running over the entire lateral surface of the hemisphere, from the great longitudinal fissure to the lateral fissure.
The central sulcus
41
A sulcus which runs parallel to the upper margin of the corpus callosum.
The cingulate sulcus
42
What is the importance of the precentral gyrus?
It contains the primary motor cortex
43
What the highest level in the brain for the control of movement?
The primary motor cortex
44
Lies in the post-central gyrus.
The primary somatosensory cortex
45
Carrying the modalities of touch, pressure, pain and temperature.
The primary somatosensory cortex
46
Where does the visual cortex located on?
On the calcarine sulcus
47
Where does the auditory cortex located on?
The superior temporal gyrus
48
What does the limbic lobe consist of?
The cingulate gyrus, hippocampal formation and amygdala
49
What is the function of the limbic lobe?
Has complex structures concerned with emotional aspects of behavior and with memory
50
What does the corpus striatum consist of?
The caudate nucleus, the putamen and the globus pallidus
51
What is the basal ganglia?
Masses of grey matter, lie deep in the hemispheres on the medial and lateral side of the internal capsule.
52
What is the function of the basal ganglia?
Control of muscle tone, posture and movement
53
Part of the corpus striatum, lies in the wall of the lateral ventricle.
The caudate nucleus
54
Where does the cell body located in the first order neuron?
Dorsal root a of spinal nerve or in the trigeminal ganglion
55
Where does the cell body of the second order neuron located?
In the spinal cord or brainstem
56
Where does the axons of the second order neuron terminate?
In the thalamus
57
Where does the cell body of the third order neuron located?
In the thalamus
58
Its axons projects to the somatosensory cortex.
The third order neuron
59
The motor neurons that directly innervate skeletal muscles, and have cell bodies in the grey matter of the spinal cord.
The lower motor neurons
60
Neurons that control the activity of lower motor neurons.
The upper motor neurons
61
A motor pathway controls the activity of motor neurons located in cranial nerve nuclei.
The corticobulbar or corticonuclear fibers
62
This motor pathway innervate the skeletal muscles of the head and neck.
The corticobulbar or corticonuclear
63
This motor pathway innervates the muscles of the trunk and limbs.
The corticospinal fibers.
64
Forms a ridge on the ventral surface of the medulla.
The corticospinal fibers
65
Known as the pyramidal tract.
The corticospinal tract
66
Extrapyramidal tracts.
Vestibulospinal - reticulospinal tracts - basal ganglia
67
Which tracts Control muscle tone and posture of the body?
Vestibulospinal + reticulospinal tracts
68
From where does the cerebellum receives afferent fibers?
The spinocerebellar tracts - the vestibular system - the motor cortex
69
Lesion of the dorsal columns of the spinal cord.
Ipsilateral loss of touch/proprioception below the level of the lesion
70
Lesion of the spinothalamic tract.
Contralateral loss of pain/temperature below the level of the lesion
71
What do you expect in a patient with unilateral lesion of the thoracic spinal cord.
1- ipsilateral loss of touch sensation and and proprioception.
2- contralateral loss of pain and temperature sensation in the trunk and lower limbs.
72
A patient with ipsilateral loss of touch sensation and proprioception on the right leg, and contralateral loss of pain and temperature sensation on the other leg, he also has hyper-reflexia in the right leg. What can be the diagnosis?
Brown Sequard syndrome ( unilateral lesion of the thoracic spinal cord )
73
What do you expect with a patient with a lesion in the brainstem of the medial lemniscus?
Loss of touch sensation
74
Lesion of the trigeminothalamic tract.
Loss of pain and temperature sensation in the face
75
What is the difference between the corticobulbar and the corticospinal tracts?
The corticobulbar tract: innervate skeletal muscles of the head and the neck.
The corticospinal tract: innervate skeletal muscles of the trunk and limbs
76
A patient comes with loss of digits movement,breakdown in movement of extensions, abduction of the upper limbs and flexion of the lower limbs.
Pyramidal weakness ( UMNL )
77
What are the characteristics of LMN syndromes?
- Paresis.
- Plegia.
- Wasting of muscles.
- Fasciculation.
- Hypotonia.
- Hyporeflexia or areflexia.
78
What are the characteristics of UMN syndromes?
- Pyramidal weakness.
- No wasting of muscles.
- Hyperreflexia.
- Spasticity.
- Positive Babinski response.
- Absent abdominal reflexes.
79
What is Clasp-knife response ( characteristic of UMN lesion )?
Increase of tone at the initial stretch of the limb muscle followed by relaxation of tone.
80
Unilateral lesion in the cerebral hemisphere or brainstem result in.
Contralateral paralysis of the limbs
81
Cerebellar syndrome signs and symptoms.
Nystagmus - dysarthria - intention tremor - ataxia.
82
What is Romberg’s sign?
Loss of balance when the patient closes his eyes due to sensory ataxia
83
Unilateral lesion of these nerve fibers lead to contralateral motor disorder.
Unilateral lesion of the basal ganglia
84
What are the characteristics of Parkinson’s disease?
- Akinesia or bradykinesia.
- Festinant gait and sudden stops.
- Flexed posture.
- Absence of arm-swinging when walking.
- Laking facial expressions.
85
Postural tremor.
Fast and present while maintaining posture.
86
Resting tremor.
Slow and present at rest
87
What type of tremors occur in Parkinson’s disease?
Resting tremor
88
What type of tremors occur in thyrotoxicosis?
Postural tremor
89
Increase in muscular tone that manifest resistance to passive movement throughout the extent of the movement.
The rigidity
90
What is the difference between rigidity and spasticity?
Rigidity: increased muscle tone along the entire movement.
Spasticity: increased muscle tone at the initiation of the movement then relaxation occur.
91
What are the signs and symptoms of basal ganglia disorders?
- Akynesia or bradykinesia.
- Rigidity.
- Dyskinesia, tremor, dystonia.
“ affect the contralateral side of the lesion “
92
A basal ganglia sign that can be seen in Huntington’s disease.
Chorea
93
What is the largest part of the hindbrain?
The cerebellum
94
The functions of this part of the hindbrain are entirely motor and it operates at an unconscious level.
The cerebellum
95
Controls balance, posture, muscle tone and coordination of movements.
The cerebellum
96
The cerebellum consist of two hemispheres connected laterally by.
The vermis
97
What are the layers of the cerebellar cortex?
Outer - Molecular layer.
Intermediate - Purkinje cell layer.
Inner - Granular layer.
98
The afferent fibers entering the cerebellum proceeds to the cortex as.
Mossy fibers or climbing fibers
99
All the afferent fibers originating elsewhere than the inferior olivary nucleus end as.
Mossy fibers
100
Branch in the cerebellum to supply several folia and end in the granular layer.
The mossy fibers
101
The only axons that leave the cerebellar cortex.
The axons of Purkinje cells
102
Form where does the climbing fibers originate from?
Originate from the inferior olivary nucleus of the medulla
103
Provides discrete excitatory input to Purkinje cells
The climbing fibers
104
What is the neurotransmitter of the Purkinje cells?
GABA “inhibition of cells in the cerebellar nuclei
105
What are the four cerebellar nuclei?
- Fastigial nucleus.
- Globose nucleus.
- Emboliform nucleus.
- Dentate nucleus.
106
What is the largest cerebellar nucleus?
The dentate nucleus
107
From where does the dentate nucleus receive afferent fibers?
The inferior olivary nucleus
108
Constitutes the primary source of efferent fibers form the cerebellum to other parts of the brain.
The cerebellar nuclei
109
What are the principal destinations of the efferent fibers of the cerebellar nuclei?
- Reticular and vestibular nuclei of the medulla and pons.
- Red nucleus of the midbrain.
- Ventral lateral nucleus of the thalamus.
110
Midline lesion of the cerebellum leads to.
Loss of postural control ( despite preserved coordination of the limbs )
111
What can be result from a unilateral lesion of the cerebellar hemispheres?
Symptoms and signs of the same side
112
What can be result from a unilateral cerebellar hemispheric lesion?
Ipsilateral incoordination of the arm ( intention tremor ) and of the leg, causing unsteady gait
113
What are the signs and symptoms of a bilateral dysfunction of the cerebellum? ( in alcohol intoxication, hypothyroidism, MS, paraneoplastic disease )
Dysarthria - Cerebral ataxia
114
A very common feature of multiple sclerosis.
Nystagmus
115
What is “Charcot’s triad“ ?
The combination of nystagmus + dysarthria + intention tremor.
( indicates MS )
116
What is the largest part of the three basic embryological divisions of the brain?
The forebrain
117
Part of the forebrain, lies between the brainstem and the cerebral hemispheres.
The diencephalon
118
What does the diencephalon consist of?
Epithalamus - Thalamus - Subthalamus - Hypothalamus
119
A small elevation caudal to the optic chiasm.
The tuber cinereum
120
From where does the infundibulum extends?
From the apex of the tuber cinereum
121
What forms the lateral wall of the third ventricle?
The ventral part - the hypothalamus.
| The dorsal part - the thalamus.
122
Part of the diencephalon, lies immediately rostral to the superior colliculus of the midbrain.
The epithalamus
123
What does the epithalamus consist of?
The pineal gland + Habenula
124
Radiation of fibers between the internal capsule to the cortical surface.
The corona radiata
125
A cortical area within the depths of the lateral fissure.
The insula
126
Become continuous with the parahippocampal gyrus.
The cingulate gyrus
127
Necessary for conscious awareness, thought, memory and intellect.
The cerebral cortex
128
What are the major interhemispheric commissural fibers.
Corpus callosum - anterior commissure - hippocampal commissure
129
Part of the corpus callosum, which contributes to visual functions.
The splenium
130
Alexia without agraphia can result from.
Destruction of the splenium of the corpus callosum
131
A commissural fibers that interconnect the inferior and middle temporal gyri and the olfactory regoins of the two sides.
The anterior commissure
132
Transverse fibers linking the posterior columns of the fornix of each side.
The hippocampal commissure
133
A projection fibers lies between the thalamus and the caudate nucleus medially and the lentiform nucleus laterally.
The intarnal capsule
134
Which part of the internal capsule contains corticobulbar and corticospinal motor fibers?
The posterior limb of the internal capsule
135
Consist of fibers arising from the medial and lateral geniculate nuclei of the thalamus that pass to the auditory and visual cortices.
The retrolenticular part
136
The most rostral and ventral part of the corpus striatum.
The nucleus accumbens
137
Provides an important link between the basal ganglia and the limbic system. “Through its close connection with the amygdala”
The nucleus accumbens
138
Associated with reward, gratification and addictive aspects of behavior.
The nucleus accumbens
139
Lentiform or lenticular nucleus.
Globus pallidus + putamen
140
What does the medial surface of the lentiform nucleus lies against?
Lies against the genu of the internal capsule
141
The striatum or neostriatum ( caudate nucleus + putamen )is almost separated by.
The anterior limb of the internal capsule
142
What does the striatum consist of?
Caudate nucleus + putamen
143
Lies lateral to the internal capsule and the globus pallidus.
The putamen
144
What separates the putamen and the globus pallidus?
The lateral medullary lamina
145
Separates the external capsule from the extreme capsule.
The claustrum
146
Lies lateral to the extreme capsule.
The cortex of the insula
147
What separates the head of the caudate from the putamen?
The internal capsule
148
What separates the external and the internal segments of the globus pallidus?
The medial medullary lamina
149
Efferent projections of the striatum are directed to.
The striatipallidal + striatonigral fibers
150
From where does the pallidal afferents arise?
The striatum and the subthalamic nucleus
151
The pallidal efferents projects to.
The subthalamus and thalamus
152
Describe the pathways of the pallidothalamic fibers?
Ansa lenticularis- pass round the anterior margin of the internal capsule.
Lenticular fasciculus- pass through the internal capsule.
Thalamic fasciculus- enter the thalamus from its ventral aspect.
153
Used for the treatment of Parkinson’s disease.
Levodopa
154
What is the pathological hallmark of Parkinson’s disease?
Degeneration of the dopaminergic neurons of the pars compacta of the substantia nigra and depletion of striatal dopamine
155
What is the 2nd treatment option for Parkinson’s disease?
1- neurosurgical lesion of the internal segment of the globus pallidus.
2- stimulation of the subthalamic nucleus through an implanted electrodes.
156
What is the pathological hallmark of Huntington’s disease?
Progressive degeneration of the striatum and cerebral cortex.
157
Between the two rostral limits of the two crura cerebri.
The mammillary bodies
158
Largest inputs to the hypothalamus comes from.
The hippocampus + the amygdala.
159
Concerned with baroreceptors and chemoreceptors.
The nucleus solitarius of the medulla
160
What does the hippocampal formation consist of?
Hippocampus + dentate gyrus + parts of para hippocampal gyrus
161
Formed by infolding of the inferomedial part of the temporal lobe into the lateral ventricle.
The hippocampus
162
Lies between the hippocampus and the parahippocampus
The dentate gyrus
