11. Functional connectivity of the sensory cortex, thalamus and insula. Somato- & viscerosensory innervation of the head-& neck region (trigeminal system) Flashcards
1
Q
Name 4 associative cortex
A
- Frontal
- Parietal
- Temporal
- Occipital
2
Q
Name 4 secondary cortex
A
- Motor
- Somatosensory
- Visual
- Auditory
3
Q
How can the information flow from secondary cortex to effector?
A
Secondary cortex
-> Primary motor cortex
-> Basal ganglia (somatomotor system); Hypothalamus (visceromotor system)
-> Brain stem - medial nuclei
-> spinal cord - anterior horn
-> effector
4
Q
How can information flow from receptor to secondary cortex?
A
Receptor
-> Spinal cord - spinal ganglion
-> brainstem - lateral nuclei
-> Thalamus
-> Primary somatosensory & special sensory cortex
-> secondary cortex
5
Q
How can information flow from receptor to secondary cortex?
A
Receptor
-> Spinal cord - spinal ganglion
-> brainstem - lateral nuclei
-> Thalamus
-> Primary somatosensory & special sensory cortex
-> secondary cortex
6
Q
What type of cortex can you find in granular cortex?
A
Primary somatosensory cortex
7
Q
In granular cortex, what type(s) of fibers can you find? Where do they terminate?
A
The afferent fibers of the thalamus terminate (layer IV)
8
Q
Where does granular cortex locate?
A
The post central gyrus
9
Q
Which layers are thickened in granular cortex?
A
The external and internal granular layers (II & IV) are thickened
10
Q
Which cortex is agranular cortex?
A
Primary somatomotor cortex
11
Q
In agranular cortex, what type(s) of fibers can you find?
A
The efferent fibers project to the motor nuclei of the cranial nerves and motor columns of the spinal cord
12
Q
Where does agranular cortex locate?
A
Located in the precentral gyrus
13
Q
Which layers of agranular cortex are thickened?
A
The pyramidal layers (III & V)
14
Q
Where is primary sensory cortex located? At which lobe? Bordmann number?
A
- Located in post central gyrus
- Parietal lobe
- Brodmann 3,1,2
15
Q
Primary sensory cortex
-> Where do afferent fibers come from?
A
From the body (via posterolateral ventral and posteromedial ventral nuclei of thalamis) and association nuclei of thalamus
16
Q
Primary sensory cortex
-> Where do efferent fibers go?
A
To the primary motor area, secondary somatosensory area and association areas
17
Q
What is the function of primary sensory cortex?
A
Somatosensory sensation
18
Q
Where are association somatosensory areas located? At which lobe? Brodmann number?
A
- Located in the superior and inferior parietal lobules
- Parietal lobe
- Brodmann 5, 7
19
Q
Where do afferent fibers of association somatosensory areas come from?
A
From the somatosensory & association cortical areas & thalamic nuclei (posterior and intralaminar nuclei)
20
Q
Where do efferent fibers of association somatosensory areas go to?
A
To somatosensory & association cortical areas & thalamic nuclei
21
Q
What are the 3 main functions of association somatosensory areas?
A
- Integrate somatosensory activity
- Perception of moving
- Orientation in space
22
Q
Where does secondary somatosensory area locate? At which lobe?
A
- Located in the small area in the postcentral gyrus, next to the lateral sulcus
- Parietal lobe
23
Q
Where do afferent fibers of secondary somatosensory area come from?
A
From the primary somatosensory area & thalamus
24
Q
What is the function of secondary somatosensory area?
A
Reacts to skin stimulation
25
Where does primary visual area locate?
In the calcarine sulcus and adjacent cortex of the occipital lobe
26
Where do afferents of primary visual area come from?
From the lateral geniculate nuclei via the optic radiation
27
Where do efferents of primary visual area go to?
To the secondary visual area
28
What is the function of primary visual area
Responsible for perception and realization of objects in the visual field
29
Where does secondary visual area locate?
Next to the primary visual area
30
Where do afferents of secondary visual area come from?
from the primary visual area
31
Where do efferents of secondary visual area go to?
To the pretectal area, premotor cortex and frontal eye field (FEF)
32
What is the function of secondary visual area?
Detailed analysis of the visual field and objects
33
Where is primary auditory area located?
Transverse temporal gyri of Heschl
34
Where do afferents of primary auditory area come from?
From the medial geniculate nuclei via the acoustic radiation
35
Where do efferents of primary auditory area go to?
To the secondary auditory area
36
What is the function of primary auditory area?
Responsible for perception and realization of tones, sounds, and voices
37
Where is secondary auditory area located?
In the superior temporal gyrus next to the primary auditory area
38
Where do afferents of primary auditory area come from?
From the primary auditory area and medial geniculate nuclei
39
Where do efferents of secondary auditory area go to?
To the association and speech areas
40
What is the function of secondary auditory area?
Responsible for distinguishing and analyzing and perception of complex sounds, tones and voices
41
Where is the gustatory area located?
In the opercular part of postcentral gyrus and adjacent cortex of the insular lobe
42
Where do afferents of gustatory area come from?
From the nuclei of solitary tract via the thalamic ventral posteromedial nucleus
43
What is the function of gustatory area?
Gustatory perception
44
Where is olfactory area located?
Parahippocampa gyrus (entorhinal area)
45
Where do afferents of olfactory area come from?
From the olfactory bulb and lateral olfactory stria
46
Characteristic(s) of interconnection of olfactory area?
Reciprocal with the orbitofrontal association cortex
47
What is the function of olfactory area?
Responsible for perception and distinguish of olfactory stimuli
48
Where is vestibular area located?
A small region of the postcentral gyrus next to the lateral sulcus
- Opposite to the auditory area in the superior temporal gyrus
49
Where do afferents of vestibular area come from? (BA 2v)
From ventral posteromedial nucleus of thalamus
50
What is the function of vestibular area?
Perception of head position in respect to the rest of the body and head movements
51
What is the largest structure in the diencephalon?
Functional connectivity of thalamus
52
What are the 4 functions of thalamus?
1) Relay sensory in to the cortex
2) Motor circuits
3) Limbic system
4) Reticular formation
53
What are the 5 main anatomical groups of nuclei
1. Anterior group
2. Medial group
3. Lateral group
4. Intralaminar and paraventricular nuclei
5. Rostral nuclei of recticular formation
54
Which are nuclei of anterior group?
Anterior nuclei
55
which are nuclei of medial group?
Medial dorsal nuclei
56
What are the 2 groups of lateral group of nuclei?
Dorsal and ventral groups
57
What are the 3 nuclei of dorsal group (within lateral group)?
3.1 Lateral dorsal nucleus
3.2 Lateral posterior nucleus
3.3 Posterior nuclear complex
58
What are the 4 nuclei of ventral group (within lateral group)?
3.4 Ventral anterior nucleus
3.5 Ventral lateral complex
3.6 Ventral posterolateral nucleus
3.7 Ventral posteromedial nucleus
59
What are the 2 nuclei within Intralaminar & paraventricular nuclei?
4.1 Intralaminar nuclei
4.2 Paraventricular nuclei
60
What is the nucleus within rostral nuclei of reticular formation group?
Reticular nucleus of thalamus
61
What are the 3 main functional nuclei group of thalamus?
1. Specific nuclei
2. Nonspecific nuclei
3. Association nuclei
62
What is the function of specific nuclei?
Receive specific information from visual, acoustic, primary motor somatosensory and motor input
63
What are the 5 main specific nuclei?
Ventral anterior nucleus
Ventral lateral nucleus
Ventral posterior nucleus
Medial geniculate nucleus
Lateral geniculate nucleus
64
What is the function of nonspecifc nuclei?
Have broad projections through the cerebral cortex, & can be involved in general functions such as consciousness & attention.
65
What are the 3 main nonspecific nuclei?
Reticular nucleus
Intralaminar nucleus
Paraventricular nucleus
66
What is the function of association nuclei?
Receive most of the information from the cerebral cortex, & project back to the “association areas” in the cortex to regulate the integration and interpretation of the sensory information.
67
What are the 3 main association nuclei?
1. Anterior nucleus
2. Pulvinar
3. dorsomedial nucleus
68
Where do affferents of ventral polatseral nucleus (VPL) come from?
From the spinal cord
69
Where do efferents of ventral polatseral nucleus (VPL) go to?
To the primary somatosensory area (BA 3, 1, 2) in the postcentral gyrus
70
What is the function of ventral polatseral nucleus (VPL)?
Somatosensory information from the trunk and limbs
71
Where do afferents of ventral posteromedial nucleus (VPM) come from? (for the somatosensory information from the head)
From the trigeminal nerve
72
Where do efferents of ventral posteromedial nucleus (VPM) go to? (for the somatosensory information from the head)
To the primary somatosenosry area for the head (BA 3, 1, 2) in the postcentral gyrus
73
Where are afferents of ventral posteromedial nucleus (VPM) come from? (for the function of sense of taste)
From the gustatory nucleis (solitare-thalamic tract)
74
Where do efferents of ventral posteromedial nucleus (VPM) go to? (for the function of sense of taste)
To the gustatory area (BA 43) in the inferior frontal gyrus (its opercular part)
75
Where do afferents of anterior ventral nucleus come from?
Mainly from the lobus pallidus, reticular formation, substantia nigra, and cerebellum
76
Where do efferents of anterior ventral nucleus go to?
To the preemptor area (BA 6) in the frontal gyri
77
What is the function of anterior ventral nucleus?
Motor circuits of basal nuclei and motor planning and control
78
Where do afferents of lateral ventral complex come from?
Mainly from the cerebellum, globus pallidus. red nucleus and substantia nigra
79
Where do efferents of lateral ventral complex go to?
To the primary motor area (BA 4) in the precentral grys
80
What is the function of lateral ventral complex?
Motor circuit of cerebellum, basal nuclei and cortex
81
Describe appearance of Thalamocortical fibers (TCF) (in 1 word)
Bush
82
Thalamocortical fibers (TCF) -> Via ______ —> project to the layers of the cortex
internal capsule
83
TCF —> Via internal capsule —> project to the layers of the cortex
=> What are these cortices?
visual cortex, somatosensory cortex, auditory cortex
84
Thalamocortical fibers (TCF) works with which areas?
gustatory & olfactory pathways & pre-frontal motor areas
85
Where do insular areas locate? BA number?
Located in the insular lobes
Brodmann 13–16
86
Where do afferents of insular areas come from?
From the ventral posteromedial, ventral posterolateral & intralaminar nuclei of thalamus
87
Where do efferents of insular areas go to?
1. Frontal lobe
2. Parietal lobe
3. Temporal lobe
4. Cingular gyrus
5. Amygdaloid body
6. Entorhinal cortex
7. Periamygdalar area of olfactory cortex
88
Insular areas have 3 parts which are ____
1 Viscerosensory part (ventral part of the insular lobe)
2 Motor part (middle part of the insular lobe)
3 Vestibular part (dorsal part of the insular lobe)
89
What is the function of Viscerosensory part (ventral part of the insular lobe)?
- Perception of gustatory stimuli
- Integration with olfactory perception
- Regulation of the immune system
90
What is the function of Motor part (middle part of the insular lobe)?
- Influences respiratory movements & activity of the breathing muscles
- Activity of the articulation muscles & their association with speech production
- Influences gastrointestinal tract motility (peristalsis)
91
What is the function of Vestibular part (dorsal part of the insular lobe)?
Participates in perception of head position & movements
92
Location of prefrontal areas
* Prefrontal area of frontal gyri (rostral part)
* Orbital gyri
* Straight gyrus (gyrus rectus)
* Cingulate gyrus
93
What are the functions of prefrontal areas?
* Cortical center of emotions
* Behavior - planning
* Ego
* Personality
* Cortical center of creative thinking
* Complex memory circuits
94
# Somato- & viscerosensory innervation of the head-& neck region
What are the 4 nulcei of trigeminal system?
1. Trigeminal motor nucleus
2. Mesencephalic trigeminal nucleus (pseudo-unipolar neurons)
3. Pontine nucleus (princeps sensory nucleus)
4. Spinal trigeminal nucleus
95
Somato- & viscerosensory innervation of the head-& neck region
=> What is the location of trigeminal motor nucleus?
Pons (tegmentum)
96
Somato- & viscerosensory innervation of the head-& neck region
=> What is the role of trigeminal motor nucleus?
1. Branchiomotor (BM)
2. Special visceromotor nucleus (SVM)
3. Ventro-lateral column
97
Somato- & viscerosensory innervation of the head-& neck region
=> What is the location of Mesencephalic trigeminal nucleus?
Midbrain (peri-aqueductal gray matter)
98
Somato- & viscerosensory innervation of the head-& neck region
=> What is the location of Mesencephalic trigeminal nucleus?
Midbrain (peri-aqueductal gray matter)
99
Somato- & viscerosensory innervation of the head-& neck region
=> What is the role of Mesencephalic trigeminal nucleus?
1. General somato-sensory (GSS)
2. Proprioceptive (joint position)
3. (Masseteric reflex)
100
What is the location of Pontine nucleus (princeps sensory nucleus)?
Pons (tegmentum)
101
What is the function of Pontine nucleus (princeps sensory nucleus)?
* General somato-sensory (GSS)
* Pons (tegmentum)
* Epicritic (fine touch, pressure, vibration)
102
What is the location of Spinal trigeminal nucleus?
Pons, Medulla oblongata & extends till the substantia gelatinousa of the C1,C2
103
What is the function of spinal trigeminal nucleus?
General somato-sensory (GSS)
Protopathic (pain, temperature)
104
What is the synonym for Reflex arc of Mastication?
Jaw jerk reflex
105
Definition of Reflex arc of Mastication
a stretch reflex (proprioceptive, monosynaptic reflex) used to examine the condition of a patient's trigeminal nerve.
106
When this reflex arc of Mastication is tested?
The masseter reflex examination is performed when there are signs of damage to the trigeminal nerve.
107
What is proprioception?
Information about position of the muscles & joints – afferent inputs coming from muscle spindles, tendon organ!
108
What o sthe procedure for Reflex arc of Mastication test
* Ask the patient to relax the jaw!
* Place the finger on the chin.
* The mandible is tapped downward while the mouth is held slightly open.
* In response —> the masseter muscles will move the mandible upward.
109
Reflex arc of Mastication (Masseter reflex)
Receptor to effector pathway?
110
Trigeminal lemniscus is made of __
f 2nd order neuronal axons in the brain steam.
111
Trigeminal lemniscus carries sensory information from the trigeminal system to which nucleus?
The ventral posteromedial (VPM) nucleus of the thalamus.
112
What is the role of Trigeminal lemniscus?
It brings tactile, pain, and temperature impulses from the skin of the face, the mucous membranes of the nasal and oral cavities, and the eye, as well as proprioceptive information from the facial and masticatory muscles.
113
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Mammillary body (mammilothamic tract)
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
114
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Dentate nucleus (cerebellum), pallidum
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
115
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Spinal cord (spinothalamic tract), dorsal column nuclei (medial lemniscus)
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
116
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Spinal and main trigemini nuclei (trigeminal lemnisucs), ascending fibers from the solitary nucleus
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
117
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Amygdaloid nucleus
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
118
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Spinal cord (spinothalamic tract), dorsa column
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
s
119
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Cerebral cortex
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
120
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Thalamus
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
121
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Inferior colliculus
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
122
CONNECTIONS AND FUNCTIONAL SIGNIFICANCE OF THE THALAMIC NUCLEI
1. Source of the main afferent connection:
- Retina (optic nerve and tract)
2. nucleus: ?
3. Main efferent connection: ?
4. Functional significance: ?
