Thalamus Flashcards
(48 cards)
In the basic pathway of sensory interpretation, what is the general function of the thalamus?
Helps make a “decision” on what do to with the ascending info (analyzes it) before it goes to consciousness (“decides” what info passes)
- Different sensory modalities come together here
What 2 major brain regions can thalamic output go to?
- Cerebrum
- Striatum
What are the parts of the striatum?
Caudate nuc. + putamen
What are 2 major e.g.’s of sensory info that does NOT go to the thalamus?
- Olfaction
- Unconscious proprioception (str8 to cerebellum)
Besides ascending sensory info, what other major category of info does the thalamus receive?
What 2 major brain regions might provide this info to the thalamus?
Motor
- E.g. from cerebellum and basal ganglia
What’s the proper name of the thalamus?
Dorsal thalamus
Name the divisions of the diencephalon.
- Epithalamus
- Dorsal thalamus
- Subthalamus
- Hypothalamus
What is contained w/in the epithalamus?
Pineal gland, habenula, stria medullaris
What is contained w/in the subthalamus?
Subthalamic nuclei, zona incerta
What are the 4 major thalamic divisions?
Which one divides into 3 more?
Which looks like a thalamic cape and acts as a filter?
- Internal medullary lamina (divides into 3)
- Intralaminar nuclei (w/in lamina)
- Midline nuclei
- Thalamic reticular nuclei (cape/filter-specificity)
Name the 3 divisions of the internal medullar lamina.
What is the shape of the lamina that divide them?
- Anterior division nuclei
- Lateral division nuclei
- Medial division nuclei
(Y-shaped)
Which ventricle does the thalamus form a wall? Which of said ventricle’s walls does it form?
- 3rd ventricle’s lateral wall
The internal capsule divides the thalamus from the _________________.
Which is medial/lateral?
Lentiform nucleus
- Thalamus is medial
Which ventricular space can be found superior to the thalamus?
Body of lateral ventricle (x2)
What can be found superolateral to the thalamus, adjacent to the body of the lateral ventricle?
Caudate nucleus
What are internal capsule fibers known as before they become the internal capsule?
Corona radiata
The thalamus consists of a majority of ________ neurons but also _______ neurons.
(what NT would each of these typically use?)
- Projection (glutamate)
- Inhibitory (GABA)
The majority of thalamic input can be considered __________ but there is also some __________ input.
- Regulatory (e.g. cortex, thalamic reticular nucleus, reticular formation, aminergic projections)
- Specific (e.g. DCP)
What are the 3 grouping of thalamic nuclei? Differentiate them.
- Specific or relay nuclei–*well-defined input and projections
- Association nuclei–*reciprocally connected to association cortex
- Non-specific nuclei–*project to broad areas of cortex
As noted in the homunculus, the VPM of the thalamus relays to what part of the body? What about the VPL?
- Head, tongue (VPM receives from CN V)
- Everything else (VPL receives from DCP/SST)
(looks like man on his knees, sticking out tongue towards medial)
Specific/relay nuclei have specificity but they also _______________ w/each other.
Collaborate
The anterior nucleus, ventral anterior/ventral lateral nucleus, VPM, VPL, MGN, LGN of thalamus fit into which category of thalamic nuclei?
Specific or relay nuclei
What are 2 major association areas of the cerebrum that association nuclei might project to?
Can they project back to the thalamus?
- Prefrontal cortex
- Parietal-occipital-temporal cortex
- Yes, these areas can project back to association nuclei of thalamus
What 3 brain regions might give regulatory input to the relay/specific or association nuclei?
- Cerebral cortex
- Reticular formation
- Reticular nucleus
