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Flashcards in Thalamus Deck (20)
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1
Q

Nuclear groups of the thalams

A
Anterior
Medial (Dorsomedial)
Lateral
Posterior
Intralaminar
Other
2
Q

Anterior Nuclear Group

A

Anterior Nucleus:

afferents: Mammilothalamic tract, Hippocampal afferents via fornix
efferents: To Cingulate Gyrus

3
Q

Medial Nuclear Group

A

Dorsomedial nucleus

Amygdala and Olfactory Cortex –> DM –> Prefrontal cortex

Sub. Nigra pars Reticulata –> DM –> Frontal Eye feilds in Middle frontal gyrus. (Brodman 8)

4
Q

Posterior Nuclear Group

A

Pulvinar - Lateral Geniculate - Medial Geniculate

5
Q

Pulvinar connections

A

Association cortices –> Pulvinar –> Diffuse cortex projections

Retina –> Pulvinar –> Visual Association Cortex V2, V3
Superior Colliculus –> Pulvinar –> Visual Association Cortex, extrastriate cortices)
Both of the above are Extrageniculate Ocular Pathways

6
Q

Reticular Nucleus connections

A

Interthalamic connections, Reticular Nucleus links thalamic nuclei to one another.

It also recieves diffuse cortical afferents.

7
Q

Lateral Geniculate body connections

A

Retinal Ganglion cells –> LGB –> Primary visual cortex

Ipsilateral fibers (from ipsilateral temporal visual field) go to layers 2,3,5
Contralateral fibers (from contralateral nasal visual field) go to layers 1,4,6
8
Q

Medial Geniculate body connections

A

Inferior Colliculus –> MGB –> Primary Auditory cortex and Secondary auditory cortex B41 and B42.

9
Q

Lateral Nuclear Group

A
Lateral Dorsal Nucleus -  LD
Lateral Posterior Nucleus -  LP
Ventral Anterior -  VA
Ventral Lateral -   VL
Ventral Posteromedial -  VPM
Ventral Posterolateral -   VPL
10
Q

Ventral Anterior Nucleus connections

A

Medial Globus Pallidus and Sub. Nigra pars reticulata –> VA –> Premotor Cortex.

ARAS –> Intralaminar Thalamic Nuclei –> VA –> Diffuse Frontal Projections

11
Q

Intralaminar Nuclei connections

A

ARAS –> Rostral Intralaminar Nuclei –> VA thalamic nucleus

12
Q

Ventral Lateral Nucleus connections

A

Output nuclei of basal ganglia —> VL anterior portion –> Supplementary Motor Cortex

Contralateral Deep Cerebellar Nuclei –> VL posterior portions –> Premotor Cortex and Primary Motor Cortex.

13
Q

Lateral Dorsal Nucleus connections

A

Limbic lobe and Parietal region –> LD –> Cigulate Gyrus and Medial Parietal Cortex

14
Q

Lateral Posterior Nucleus connections

A

Superior Parietal Lobule –> LP –> Superior Parietal Lobule

15
Q

Ventral Postero Lateral Nucleus connections

A

Medial Lemniscus and Spinothalamic Tract –> VPL –> Primary and Secondary Somatosensory Cortex.

16
Q

Ventral Postero Medial Nucleus connections

A

Principle Sensory Nucleus of Trigeminal Nerve and the Spinal Trigeminal Nucleus (Dorsal Trigeminal Nucleus) => Trigeminal lemniscus
–>
VPM –> Primary Secondary Somatosensory Cortex

Nucleus of Solitary Tract (STN) –> VPM parvocellular cells –> Parietal Operculum taste area Brodman 43.

*The VPM/VPL has a somatotopic organization of corresponding neurons relaying the sensory afferents

17
Q

What are the intralaminar nuclei?

A
The Rostral Intralaminar Nuclei, don't need names
and the
Caudal Intralaminar Nuclei: 
1) the Parafascicular Nucleus
2) the Centromedian Nucleus
18
Q

Rostral Intralaminar Nuclei connections

A

Association cortices –> Pulvinar –> Diffuse cortex projections

19
Q

Caudal Intralaminar Nuclei connections

A

Medial/Internal Globus Pallidus –> Centromedian Nucleus (CM) –> Putamen and diffuse cortical

Median/Internal GP –> Parafascicular (PF) –> Caudate and diffuse cortical

20
Q

What are the major functional classifications of the thalamic nuclei?

A

Sensory Relay nuclei: VPL VPM, Lateral and medial geniculates.

Association nuclei: Dorsomedial Nuclei, Lateral Dorsal Nucleu, Lateral Posterior Nucleus, Pulvinar

Non-specific/diffuse nuclei: Midline and intralaminar nuclei

Nuclei not projecting to the cortex: Reticularis Nucleus, Parafascicularis, Subparafascicularis.