Neuroanatomy Flashcards
1
Q
What is the cerebrum divided into?
A
Frontal lobe
Temporal lobe
Parietal Lobe
Occipital Lobe
2
Q
What are sulci and gyri?
A
Sulci: valleys
Gyri: ridges
The heavy foldings of the lobar surfaces
3
Q
What are the primary (major) sulci?
A
More invariant in appearance than secondary sulci
4
Q
What is the central sulcus?
A
Divides frontal lobe from parietal lobe?
5
Q
What divides frontal lobe from parietal lobe?
A
Central sulcus
6
Q
Where is the precentral gyrus?
A
Frontal lobe
7
Q
Where is the primary motor cortex?
A
Precentral gyrus
8
Q
Where is the motor homunculus?
A
Primary motor cortex
9
Q
Where is the postcentral gyrus?
A
Parietal lobe
10
Q
What is the postcentral gyrus?
A
Primary somatosensory cortex
11
Q
Where is the sensory homunculus?
A
Primary somatosensory cortex
12
Q
What is the Sylvian fissure?
A
Lateral sulcus
13
Q
What divides the frontal lobe from the temporal?
A
Lateral sulcus
14
Q
What does the Sylvian fissure do?
A
Divides frontal lobe from temporal.
15
Q
What is the fifth lobe of the cerebrum?
A
Insula
16
Q
Where is in the insula?
A
Deep in Sylvian fissure
17
Q
What is the insula?
A
Seat of the primary gustatory cortex
18
Q
Where is the middle frontal gyrus?
A
Between the superior and inferior frontal sulci
19
Q
What is in the middle frontal gyrus?
A
Dorsolateral prefrontal cortex
20
Q
What does the dorsolateral prefrontal cortex do?
A
Executive functions
21
Q
Where is the cingulate sulcus?
A
Medial side of frontal lobe
22
Q
Where is the seat of motivation?
A
Anterior position of adjoining cingulate gyrus
23
Q
Which sulci are on the inferior surface of frontal lobe?
A
Olfactory and orbital sulci
24
Q
What does the orbitofrontal cortex do?
A
Seat of associative learning and decision-making
25
What does the superior temporal sulcus do?
Primary auditory cortex
26
What separates the superior and inferior parietal lobes?
Superior temporal sulcus
27
What does the superior temporal sulcus do?
Seat of primary auditory cortex
28
What part of the cortex is involved in executive functions?
Dorsolateral prefrontal cortex
29
Where does decision-making and associative learning occur?
Orbitofrontal cortex
30
What is the inferior parietal lobe made of?
Angular gyrus
| Supramarginal gyrus
31
What is the inferior parietal lobe important for?
Visuospatial attention
32
Where does visuospatial attention occur?
Inferior parietal lobe
33
Where is the primary visual cortex?
Calcarine sulcus in medial occiptal cortex
34
What is the sulcus in the medial occipital cortex?
Calcarine sulcus
35
What happens to higher level of associative functions in the hemispheres?
Lateralize to one or other hemisphere
36
Where is language comprehension?
Localized to left temporal corte
37
What is prosody?
Tonal modulation of speech
38
Where is prosody located?
Right hemisphere
39
Where is the dominant hemisphere?
Contralateral to dominant hant
40
What does the dominant hemisphere do?
Mediates language and speech functions
41
How can dominance be tested?
Annette's handedness scale
| Edinburgh handedness inventory
42
How many right-handed people have a dominant right hemisphere?
10%
43
How many left-handed people have a right dominant hemisphere?
20%
44
How many left handed people have left dominant hemisphere?
64%
45
How many left handed people have bilateral dominance?
16%
46
Where is the planum temporale?
Upper surface of superior temporal gyrus
| Larger on left in 65% of people
47
What is the planum temporale?
Triangular region, important for language processing.
48
What is the most asymmetrical structure in the human brain?
Planum temporale
49
Which asymmetry is reduced or reversed in schizophrenia?
Plaum temporale
50
Signs in left hemisphere lesions
```
Aphasia
Right-left disorientation
Finger agnosia
Dysgraphia (aphasic)
Dyscaculia (number alexia)
Limb aprexia
```
51
Signs in right hemisphere lesions
```
Visuospatial deficits
Anosognosia
Neglect
Dysgraphia (spatial, neglect)
Dyscalculia (spatial)
Constructional apraxia
Dressing apraxia
```
52
Which hemisphere lesion leads to face recognition?
Bilateral
53
What are the subcortical structures?
```
Limbic system
Medial Temporal structures
Basal ganglia
Thalamus
Hypothalamus
```
54
Who first described the limbic lobe?
Broca
55
Who first assigned the function of emotional processing to limbic structures?
Papez, then Maclean
56
What is the Papez circuit of the limbic system?
```
Hippocampus
Fornix
Mamillary bodies
Mammillothalamic tract
Anterior thalamic nucleus
Genu of internal capsule
Cingulate gyrus
Parahippocampal gyrus
Entorhinal cortex
Perforant pathway
Back to hippocampus
```
57
What are the boundaries of the limbic system post-Papez?
Include amygdala, septum, basal forebrain, nucleus accumbens, orbitofrontal cortex
58
Functions of limbic system?
Mediation of emotional responses via amygdala
Influencing neuroendocrine responses via hypothalamus
Reward system regulation via nucleus accumbens
59
Function of nucleus accumbens?
Reward system
60
Function of hypothalamus?
Neuroendocrine response
61
Function of amygdala?
Mediation of emotional repsonses
Fear conditioning
Emotional regulation
62
What are the medial temporal structures?
Hippocampus
Amygdala
Entorhinal and parahippocampal cortex
63
Function of hippocampus?
Memory processes
| Continuous production of new neurons in adult life
64
What is the basal ganglia?
Group of gray matter nuclei
65
What is the largest subcortical structure?
Basal ganglia
66
Function of basal ganglia?
Planning and programming of movement
| Concerting abstract thought into voluntary action
67
What is in the basal ganglia?
Striatum: caudate nucleus + putamen
Pallidum: globus pallidus
68
What are the lentiform nucleus?
Putamen and globus pallidus
69
What is the striatum in basal ganglia made up of?
Caudate nucleus
| Putamen
70
What structures are functionally related to basal ganglia but not part of structure?
Substantia nigra
| Subthalamic nuclei
71
Where does basal ganglia receive input from?
Glutamatergic corticostriatal projection
72
Who described the circuits in the basal ganglia?
Alexander
73
What are the important circuits in the basal ganglia?
```
Motor
Oculomotor
Dorsolateral prefrontal (executive)
Anterior cingulate (motivation)
Lateral orbitofrontal (social intelligence)
```
74
Which circuit in the basal ganglia is for social functioning?
Lateral orbitofrontal circuit
75
Which circuit in the basal ganglia is for motivation?
Anterior cingulate
76
Which circuit in the basal ganglia is for executive?
Dorsolateral prefrontal circuit
77
Disorders involving basal ganglia dysfunction
```
OCD
Tourette's
Huntington's chorea
Wilson's disease
CO poisoning
Hemiballismus
Parkinsonism
Fahr's disease
```
78
What basal ganglia dysfunction causes OCD?
Volumetric changes + higher blood flow to caudate nuclei.
| Increased caudate metabolism reduces after effective treatment.
79
What is he basal ganglia dysfunction in Tourette's?
Striatal dopaminergic dysfunction
80
What is the basal ganglia dysfunction in Huntington's chorea?
Degeneration of striatum - mainly caudate nucleus - and selective loss of GABAergic neurons
81
What is the basal ganglia dysfunction in Wilson's disease?
Copper deposits in lenticular nuclei
82
What is the basal ganglia dysfunction in CO poisoning?
Acute bilateral anoxic damage to basal ganglia
83
What is the basal ganglia dysfunction in hemiballismus?
Subthamalic nucleus damage - especially infarction
84
What is the basal ganglia dysfunction in Parkinsonism?
Depigmentation of substantia nigra - Lewy bodies seen.
| Striatal overactivity associated with bradykinesia
85
What basal ganglia dysfunction is linked with bradykinesia in Parkinsonism?
Striatal overactivity
86
What basal ganglia dysfunction is linked to Fahr's diease?
Progressive calcium deposition in basal ganglia.
87
What is the thalamus?
Oval mass of grey matter nuclei in subcortial region.
88
What does the thalamus do?
Relays all types of sensory information except olfaction onto cortex.
Filter sensory information in preparation for cortical processing.
Relays cerebellar and basal ganglia inputs to cerebral cortex.
89
Structure of anterior thalamus
Receives mamillothalami tract and fornix
| Connects to cingulate cortex
90
What does anterior thalamus do?
Relays information from hypothalamus and hippocampus onto frontal cortex
91
What in the thalamus is associated with visual attention?
Pulvinar
92
Where are sleep spindles in the thalamus?
Generated in reticular nucleus
93
Function of hypothalamus
Regulates physiological functions - eating, drinking, sleeping, temperature regulation
Neuroendocrine role
94
What is the ventromedial hypothalamus?
Satiety centre
95
Where is the satiety centre?
Ventromedial hypothalamus
96
Where is the feeding centre?
Lateral hypothalamus
97
What type of lesion leads to obesity in animals?
Lesion in ventromedial hypothalamus hyperphagia
98
Where is the inferior olivary nucleus?
Brainstem
99
What does the inferior olivary nucleus do?
Aids in motor coordination by projecting climbing fibres to contralateral cerebellar cortex via inferior cerebellar peduncle
100
Signs in inferior olivary nucleus lesions
Appendicular ataxia due to motor incoordination of contralateral arm and leg
Fail finger-nose test
101
Role of cerebellum
Preparing motor plan
Predicting balance needed between muscle groups to carry out action
Cognitive processes
102
Signs of cerebellar lesions
```
Ataxia
Coarse intentional tremors
Hypotonia
Past pointing
Pendular knee jerk
```
103
Function of cerebellum in schizophrenia
Disrupted cortico-cerebellar circuity can lead to cognitve dysmetria - difficulty in coordinating and monitoring process of receiving, processing and expressing information.
104
What is the brainstem made up on?
Midbrain
Pons
Medulla
105
What is the midbrain made up of?
Superior and inferior colliculi
Substantia nigra
Periaqueductal grey matter
106
What do the superior and inferior colliculi do?
Superior - conjugate gaze control
| Inferior - auditory source localization
107
What does the periaqueductal grey matter do?
Vocalization
| Freezing response to threat and pain
108
Where is the pons?
Beneath cerebeullum
| Surrounds upper helf of 4th centricle
109
Where is the medulla?
Inferior part of 4th ventricle
| Continuous with spinal cord
110
Which part of the brainstem is continuous with the spinal cord?
Medulla
111
Anatomical feature of Olfactory nerve
Runs on basal surface of frontal cortex w/o passing through thalamus.
Formed as outgrowth of forebrain.
112
Anatomy of optic nerve
Outgrowth of forebrain.
| Relays via thalamus - geniculate body.
113
Anatomy of oculomotor nerve.
Motor function.
| Supplies 4/6 of ocular muscles.
114
Anatomy of trochlear nerve.
Motor function
| Supplies superior oblique.
115
Anatomy of trigeminal nerve
Sensory + motor.
Transmits facial sensation
Controls jaw muscles
116
Anatomy of abducens nerve
Motor.
| Supplies lateral abducens.
117
Anatomy of facial nerve.
Sensory + motor.
Transmits taste sensation
Controls facial muscles.
118
Anatomy of vestibular nerve.
Transmits auditory sensation.
119
Anatomy of cochlear nerve
Transmits balance sesnation
120
Anatomy of glossopharyngeal nerve
Motor control of pharynx
Parasympathetic control of parotid gland
Taste from back of tongue
121
Anatomy of vagus nerve
Motor control of larynx and pharynx.
Parasympathetic control of viscera.
Visceral sensations.
122
Anatomy of accessory nerve.
Motor control of neck muscles.
123
Anatomy of hypoglossal
Motor control of tongue muscles
124
Where is grey matter in the cerebrum?
Outer surface
125
Where is grey matter in the spinal cord?
Inner surface
126
What does the white matter form in the spinal cord?
Anterior, lateral and dorsal columns
127
What does the dorsal column of the spinal cord carry?
Proprioceptive sensory fibres
128
What is the spinothalamic tract made of?
Anterior and lateral columns
129
What information does the spinothalamic tract carry?
Touch
Pressure
Pain
Temperature
130
What secretes CSF?
Choroid plexus in lateral, third and fourth ventricles
131
Rate at which CSf is produced
300ml/day
132
Route of CSF
```
Secreted from choroid plexus
From lateral ventricle to interventricular foramina of Monroe
Into 3rd ventricle
Into Aqueduct of Sylvius
4th ventricle
Foramen of Magendie (single)
and Foramina of Luschka (two lateral)
Subarachnoid space
```
133
How does CSF go from lateral to 3rd ventricle?
Interventricular formina of Monroe
134
How does CSF go from 3rd to 4th ventricle?
Cerebral aqueduct of Sylvius
135
How does CSF go from 4th ventricle to subarachnoid space?
Foramen of Magendie (single) and
| Foramina of Luschka (two lateral)
136
Where is the body of the lateral ventricle?
Below corpus callosum
137
What separates the two lateral ventricles?
Septum pellucidum
138
Where is the third ventricle?
Between thalamus and hpothalamus
139
Where is the fourth ventricle?
Above pons
| Below cerebellum
140
Where does obstruction to CSF commonly occur?
3rd or 4th ventricle (Foraman of Monroe)
141
What happens in communicating hypocephalus?
Impairment of CSF reabsorption in subarachnoid space due to partial occlusion of arachnoid villi
142
What does the internal carotid artery divide into?
Anterior cerebral and middle cerebral artery
143
What does anterior cerebral artery supply?
Medial and superior strip of lateral aspect of cerebral cortex up to parietal/occipital border
144
What does the middle cerebral artery supply?
Lateral aspect of cerebral cortex, including Brocas and Wernickes in dominant hemispheres
145
Which artery supplies Brocas and Wernickes?
Middle cerebral artery
146
What does the posterior cerebral artery supply?
Inferomedial temporal lobe
| Occipital lobe
147
Which artery supplies the occipital lobe?
Posterior cerebral artery
148
Where does the posterior cerebral artery arise from?
Basilar artery
149
What supplies the medulla?
Posterior inferior cerebellar arteries
| Anterior spinal branches of vertebral arteries
150
What supplies the pons?
Basilar artery
151
Signs of carotid system TIA
```
Amaurosis fugax
Aphasia
Hemiparesis
Hemisensory loss
Hemianopic visual loss
```
152
What causes amaurosis fugax?
Blockade of retinal arteries
153
Signs of vertebrobasilar TIA
```
Diplopia, vertigo, vomiting
Choking, dysarthria
Ataxia
Ataxia without agraphia
Hemisensory loss
Hemianopic visual loss
Transient global amnesia
Tetraparesis
LOC
```
154
What supplies the premotor cortex?
Anterior cerebral artery
155
What supplies the cingulum?
Anterior cerebral artery
156
Bilateral infarct of anterior cerebral artery results in which signs
```
Quadriparesis (legs weaker than arms)
Akinetic mutism (ventromedial or cingulate syndrome)
```
157
What supplies the caudate nucleus?
Recurrent artery of Huebner (branch of anterior cerebral artery)
158
Lesion effect of caudate nucleus
Initially agitated, confused
| Evolves to akinesia, abulia with mutism and personality changes
159
What supplies the lateral prefrontal cortex?
Anterior branches of upper division of middle cerebral artery
160
Signs of lesion of lateral prefrontal cortex
Planning deficits
Impairment of working memory
Apathy
161
What supplies the basal forebrain?
Anterior comunicating artery
162
Signs of lesion in basal forebrain
Akinesia
Personality change - orbitofrontal dysfunction
Confabulatory amnesia
163
What supplies the lateral medulla?
Posterior inferior cerebellar artey
164
Lesion effect of lateral medulla or of thrombus in PICA?
Wallenberg's lateral medullary syndrome.
Acute vertigo with cerebellar signs.
Ipsilateral face numbness, diplopia, nystagmus
Horners syndrome
IX/X nerve palsy with contralateral spinothalamic sensory loss and mild hemiparesis
165
When does Wallenberg's lateral medullary syndrome occur?
Thrombus in PICA
| Lesion in lateral medulla
166
Types of white matter pathways
Projection fibres
Association fibres
Commissural fibres
167
What are projection fibres?
Run vertically, connecting higher and lower centres of the brain
168
What are association fibres?
Interconnect different regions within same hemisphere of brain
169
What are commissural fibres?
Interconnect similar regions in opposite hemisphere.
170
What does the anterior commissure do?
Interconnects olfactory bulbs
171
What does the posterior commissure do?
Interconnects midbrain pretectal nuclei
172
What interconnects the posterior dorsal thalamic nuclei?
Hippocampal commissure
| Habenular commissure
173
What supplies anterior aspect and most of the body of the corpus callosum?
Pericallosal artery (from anterior cerebral artery)
174
Signs of vascular disruption to pericallosal artery?
Left sided apraxia and agnosia
175
What is the posterior aspect of the corpus callosum called?
Splenium
176
What supplies the splenium?
Posterior cerebral artery
177
Signs of vascular disruption to splenium?
Alexia and color anomia
| Preserved ability to copy words
178
Why is there preserved ability to copy words but not color in disruption of vasularity to splenium?
Motor information can be relayed via anterior corpus callosum instead
179
What is the fornix?
Connects hippocampus to hypothalamus via mamillary bodies
180
Is fornix white or grey matter?
White
181
Function of fornix
Relays cortical input to regulate neuroendocrine and autonomic systems
182
What connects Brocas and Wernickes?
Arcuate fasciculus
183
What does damage to Arcuate fasciculus result in?
Conduction aphasia
184
What is the uncinate fasciculus?
Connects orbitofrontal cortex to anterior temporal lobs.
185
Function of unicate funculus?
Social cognition
| Language
186
Who divided the cortical layers into 47 specialised areas?
Brodmann
187
What is the neocortex made up of as per Brodmann?
6 Layers
188
Which layers in the neocortex are mainly afferent?
Layers 2 and 4
189
Which layers in the neocortex are mainly efferent?
Layers 5 and 6
190
What makes up cortical neurons?
75% is pyramidal neurons
| 25% are stellate cells - not in layer 1
191
What is Layer 1?
Molecular/agranular
192
Cells in Layer 1?
Glial cells
Dendrites from neurons of deeper layers
Horizontal cells of Cajal
193
Name of Layer 2?
External Granular layer
194
Cells in Layer 2
Granule cells
| Small pyramidal cells (larger as you go down layers)
195
Name of Layer 3?
External pyramidal layer
196
Cells in layer 3?
Small and medium sized pyramidal cells
197
Name of layer 4?
Internal granular layer
198
Cells in layer 4?
Some pyramidal cells
Mostly granule cells
Receives thalamocortical inputs
199
Name of layer 5?
Internal pyramidal layer
200
Cells in layer 5?
Largest pyramidal cells - particularly motor cortex - betz cells
201
Name of layer 6?
Multiform layer
202
Cells in layer 6?
All cells
Spindle cells
Martinotti cells
Major source of corticothalamic fibres
203
Which layer gives rise to association/commissural and projection fibres?
Layer 6
204
How is the cerebelar cortex described as per Brodmann?
Three layered
Molecular - basket and stellate cells
Purkinje - Purkinje cells
Granular - granule and golgi cells
205
What are Purkinje cells?
Class of GABAergic neurons in cerebellar cortex only.
| Connect to deep cerebellar nuclei via inhibitory projections.
206
Function of purkinje cells?
For sole output of all motor coordination in cerebellum.
207
Where are granule cells?
Granular layer of cerebeullum
Layer 4 of cerebral cortex
Denate gyrus of hippocampus
Olfactory bulb
208
Where are Betz cells?
Primary motor cortex - fifth layer of grey matter.
209
What are Betz cells?
Pyramidal cell neurons - largest in CNS.
| 10% of total pyramidal cell population in layer 5 of primary motor cortex.
210
Where are stella cells?
Layer 4 of cerebral cortex (from thalamus forward to pyramidal cells)
Cerebeullum
211
What do glial cells do?
Supportive metabolic functions
| Modulate neuronal functions via neurosteroids
212
Types of glial cells
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
213
Which glial cell is most predominant?
Astrocyte
214
What are astrocytes?
Enable nutrition of neurons
Breakdown of neurotransmitters
Maintain blood-brain barrier
215
Where are oligodendrocytes?
CNS
216
What do oligodendrocytes do?
Produce myelin sheaths
217
What do microglia do?
Scavenger cells that clear neuronal debris following cell death
218
What do ependymal cells do?
Cover ventricles and facilitate csf circulation via their ciliary processes.
219
Where is the blood brain barrier located?
In endothelial cells of capillaries in the brain.
220
How do endothelial cells in brain capillaries form the blood-brain barrier?
Tight junctions with high electrical resistance as barrier against molecules.
221
How are blood capillaries separated from neurons?
Brain capillaries are in contact with foot processes of astrocytes
222
What molecules can go through blood-brain barrier?
Lipid soluble (ethanol and caffeine) via lipid membrane of cells
223
What olecues cannot go through blood brain barrier?
Water-soluble molecules such as Na and K.
224
What is the name of the brain which does not have a blood brain barrier?
Circumventricular organs
225
Examples of circum-ventricular organs
Subfornical organ
Area postrema (chemoreceptor trigger zone)
Median eminence
Posterior pituitary
226
Classification of dopaminergic pathways
Long
Short
Ultrashort
227
Long dopaminergic pathways
Nigrostriatal
Mesocortical
Mesolimbic
228
Short dopaminergic pathways
Tuberoinfundibular
| Incertohypothalamic
229
Ultrashort dopaminergic pathways
In amacrine cells in retina and olfactory system
230
Which dopaminergic pathway is the extrapyramidal pathway?
Nigrostriatal - crucial for motor control
231
Origin and destination of nigrostriatal pathway
Substantia nigra to striatum and amygdala via medial forebrain bundle
232
Effect of dopamine blockage in nigrostriatal pathway?
Dopamine deficiency - Parkinsons
| Blockade due to antipsychotics can cause extrapyramidal SEs
233
Origin and destination of mesolimbic pathway?
Ventral tegmental area to nucleus accumbens and hippocampus via medial forebrain bundle
234
Effect of dopamine blockade on nmesolimbic pathway?
Produces desirable antipsychotic effect by controlling positive psychotic symptoms
235
Origin and destination of mesocortical pathway?
Ventral tegmental area to cingulate cortex and prefrontal regions via medial forebrain bundle
236
Effect of dopamine blockade on mesocortical pathway?
Low levels of dopamine in this pathway lead to negative symptoms - alogia, anhedonia, amotivation, apathy
237
Origin and destination of tuberoinfundibular pathway?
Hypothalamus to pituitary via portal vessels
238
Effect of dopamine blockade on tuberoinfundibular pathway?
Dopamine acts as prolactin inhibitory hormone. Thus, low dopamine levels will increase prolactin.
239
Origin and destination of incertohypothalamic pathway?
Internal connections within hypothalamus
240
Effect of dopamine blockage within incertohypothalamic pathway?
Disturbed thermoregulation and weight gain
241
What are the cholinergic pathways?
Brainstem
| Basal forebrain
242
What is the brainstem cholinergic pathway?
Forms part of ascending reticular activating system.
243
Function of brainstem cholinergic pathway?
Maintains wakefulness and REM sleep.
244
Origination of brainstem cholinergic pathway?
Originates from pedunculopontine and laterdorsal tegmental nuclei.
245
What does brainstem cholinergic pathway innervate?
Thalamic relay neurons
| Reticular nuclei
246
Where does basal forebrain cholinergic pathway originate and project to?
Originates in nucleus basalis of meynert in basal forebrain
| Projects to hippocampus, frontal cortex and amygdala
247
What does degeneration of basal forebrain cholinergic pathway result in?
Alzheimer's disease
248
Where do most serotonergic neurons originate and ascend to?
Midbrain dorsal and median raphe nuclei
Ascend to innervate entire cortex, basal ganglia, thalamus
Descend to spinal cord
249
Where do noradrenergic pathways priginate and ascend to?
Originate in loculs coeruleus (pons)
Ascend to cortex via medial forebrain bundle
Descend to spinal cord
250
Most common excitatory neurotransmitter in brain?
GLutamate
251
What makes up most of the corona radiata?
Cortiofugal fibres
252
Which tracts are predominantly glutamatergic?
```
Almost all cortical descending tracts
Corticofugal fibres - corona radiata
All association and commissural fibres
Thalamocorticol
Cerebellar output from deep nuclei, subthalamic nuclei to globus pallidus projections
Brainstem to spinal cord
```
253
What is the primary inhibitory neurotransmitter?
GABA
254
What is the major transmitter for cerebral interneurons?
GABA
255
Name two major cortical interneuron subtypes
Parvalbumin-expressing interneurons (40%)
| Somatostatin-expressing interneurons (30%) - Martinotti cells
256
What can reduction in expression of parvalbumin-expressing interneurons lead to?
Schizophrenia
257
Subtypes of parvalbumin-expressing interneurons?
Basket cells
| Chandelier cells
258
What are basket cells?
Receive direct input from thalamocortical projections.
| Form synapses with soma or dendrites of pyramidal neurons
259
Function of basket cells
Provide excitatory-inhibitory balance to cortex
260
What are chandelier cells?
Form synapses with proximal axonal hillock of pyramidal neurons.
261
Function of chandelier cells?
Overall excitatory role by serving to short-circuit the action potential propagation
262
Which artery supplies the dorsolateral prefrontal circuit?
MCA
