12-8 Thalamus Flashcards
<p>Describe these 4 Divisions of the Diencephalon 1. Dorsal Thalamus 2. Epithalamus [3] 3. Subthalamus [2] 4. Hypothalamus</p>
<p>1. Dorsal Thalamus = MAIN THALAMUS 2. Epithalamus= Pineal Gland/Habenular nuclei/ [Stria medullaris] 3. Subthalamus= subthalamic nucleus & Zona incerta 4. Hypothalamus</p>
A: What is the [Stria Medullaris] and where is it found?
**SM = fibers from ____ ____ & ______ structures tht work with [______ nuclei] to allow ______ ______ to influence ______ ______ ______
B: What is the [Zona incerta] and where is it found?
A: SM= fibers from [globus pallidus] & limbic structures tht work w/[Habenular nuclei] to allow basal ganglia to influence midbrain reticular formation
A2: Found in the ePithalamus
βββββββββββββββββββββββββββ-
B: [Zona incerta] = rostral continuation of [midbrainβs reticular formation]. Found in Subthalamus
Describe the 4 Components of the of the Thalamus
A: [Internal Medullary lamina]
B: Intralaminar nuclei
C: Thalamic RETICULAR nucleus
D: Midline nuclei
B: Intralaminar nuclei= embedded in [Internal Medullary Lamina] & projects to both cerebral cortex & basal ganglia
βββββββββββββββββββββββββββ-
C: Thalamic RETICULAR nucleus= forms sheet-like structure arounds thalamus & regulates activity of thalamocortical tracts
D: Midline nuclei= rostral continuation of PAG and covers ventricular surface of thalamus
Define the 3 Functional Groups of the Thalamus
A- [Specific Relay nuclei]= bidirectional inputs & projections to SPECIFIC motor/sensory Cortex
B- [Association nuclei]= bidirectional connections to association areas of Cortex & subcortical structures
C- [Non-specific nuclei]= NON POINT-TO-POINT connections in intralaminar & midline that βawaken/prepareβ cortex for receipt
<p>A: [Thalamic RETICULAR nucleus] projects ONLY to \_\_\_\_\_ and NOT the \_\_\_\_\_. Neurons of this nuclei are \_\_\_ \_\_\_\_\_. Thalamic Axons passing thru (incoming & outgoing) give off \_\_\_\_ which travel to [Thalamic RETICULAR nucleus]. B: Main Purpose of [Thalamic RETICULAR nucleus] is to inhibit \_\_\_\_\_ and therefore Enhances activity of \_\_\_\_\_\_\_</p>
<p>[Thalamic RETICULAR nucleus] projects ONLY to other thalamic nuclei and NOT the Cerebral Cortex. Neurons of this nuclei are [inhibitory GABAergic]. Thalamic Axons passing thru (both incoming & outgoing) give off collaterals to [Thalamic RETICULAR nucleus]. B: Main Purpose of [Thalamic RETICULAR nucleus] is to inhibit random background sensory activity ---> Enhances salient activity of 1 area of thalamic neurons.</p>
<p>A: What Thalamic Afferents travel TO the [ANTERIOR nc.]? [2] B: Where does the Efferent fibers of the [ANTERIOR nc.] project to? C: What type of Thalamic nucleus is the [ANTERIOR nc.]</p>
<p>[ANTERIOR nc.] A: Aff= Mammillary body & Hippocampus ---> nc B: Eff= nc---> projects to Cingulate Gyrus C: [Specific Relay nuclei]</p>
Describe the Blood Supply for the [Internal Capsule] (3)
Internal Capsule Blood Supply:
1. [lateral striate a.] from MCA
- [Recurrent a. of Heubner] from the ACA
- [ANT Choroidal a.]
B: Specific inputs to the Thalamus use ____ as a NTS
A: PCA
Postetrior Cerebral A.
βββββββββββββββββββββββββββ-
B: Specific inputs to the Thalamus use GLUTAMATE as a NTS
<p>A: What Thalamic Afferents travel TO the VA[VENTRAL Anterior nc.]? B: Where does the Efferent fibers of the [VENTRAL Anterior nc.] project to? C: What type of Thalamic nucleus is the [VENTRAL Anterior nc.]</p>
<p>[VENTRAL Anterior nc.] A: Aff= Basal ganglia ( [substantia nigra] ) ---> nc B: Eff= nc---> projects to PreFrontal Cortex C: [Specific Relay nuclei]</p>
<p>A: What Afferents travel TO the Thalamic [VL>ant] nc. B: Where does the Efferent fibers of the Thalamic [VL>ant] nc. project to? C: What type of Thalamic nucleus is the [VL>ant]</p>
<p>[VENTRAL Lateral nc.]>ANT part A: Aff= Basal ganglia ([Globus Pallidus])---> nc B: Eff= nc---> projects to Supplementary motor area C: [Specific Relay nuclei]</p>
<p>A: What Afferents travel TO the Thalamic [VL>PoST] nc. B: Where does the Efferent fibers of the Thalamic [VL>PoST] nc. project to? C: What type of Thalamic nucleus is the [VL>PoST]</p>
<p>[VENTRAL Lateral nc.]>PoST part A: Aff= Cerebellum---> nc B: Eff= nc---> MOTOR CORTEX C: [Specific Relay nuclei]</p>
<p>A: What Afferents travel TO the Thalamic [VPM] nc. B: Where does the Efferent fibers of the Thalamic [VPM] nc. project to? C: What type of Thalamic nucleus is the [VPM] D: What type of info specifically is this Thalamic nucleus involved with?</p>
<p>[VENTRAL POSTEROMEDIAL nc.] A: (Somatic) Aff= Head --> nc B: Eff= nc---> Somatosensory Cortex C: [Specific Relay nuclei] D: Involved with relaying Vestibular information</p>
<p>A: What Afferents travel TO the Thalamic [VPL] nc. (2) B: Where does the Efferent fibers of the Thalamic [VPL] nc. project to? C: What type of Thalamic nucleus is the [VPL] D: What type of info specifically is this Thalamic nucleus involved with?</p>
<p>[VENTRAL POSTEROLateral nc.] A: (Somatic) Aff= [Trunk&Limbs] --> nc B: Eff= nc---> Somatosensory Cortex C: [Specific Relay nuclei] D: Involved with relaying Vestibular information</p>
<p>A: What Afferents travel TO the Thalamic [Lateral Geniculate] nc. (2) B: Where does the Efferent fibers of the Thalamic [Lateral Geniculate] nc. project to? C: What type of Thalamic nucleus is the [Lateral Geniculate]</p>
<p>[Lateral Geniculate nc.] A: Aff= Optic Tract & [SUP colliculus] --> nc B: Eff= nc---> [Area 17 CPVC] C: [Specific Relay nuclei]</p>
<p>A: What Afferents travel TO the Thalamic [medial Geniculate] nc. B: Where does the Efferent fibers of the Thalamic [medial Geniculate] nc. project to? C: What type of Thalamic nucleus is the [medial Geniculate]</p>
<p>[medial Geniculate nc.] A: Aff= [inf colliculus] --> nc B: Eff= nc---> Primary Auditory Cortex C: [Specific Relay nuclei]</p>