Thalamus

Question 1

VA/VL (input, nucleus, output)

Answer 1

Basal ganglia, cerebellum -> ventral anterior/ventral lateral nucleus -> motor areas (precentral gyrus, area 4)

Question 2

VPL (input, nucleus, output)

Answer 2

Medial lemniscus, spinothalamic tract (spinal components) -> ventroposterolateral nucleus -> somatosensory cortex (postcentral gyrus, area 312)

Question 3

VPM (input, nucleus, output)

Answer 3

Medial lemniscus, spinothalamic tract (trigeminal components) -> ventroposteromedial nucleus -> somatosensory cortex (postcentral gyrus, area 312)

Question 4

Medial geniculate (input, nucleus, output)

Answer 4

Brachium of inferior colliculus -> medial geniculate -> auditory cortex (transverse temporal gyri, area 41)

Question 5

Lateral geniculate (input, nucleus, output)

Answer 5

Optic nerve -> lateral geniculate -> visual cortex (occipital lobe, area 17)

Question 6

Anterior (input, nucleus, output)

Answer 6

Mamillothalamic tract -> anterior nucleus -> cingulate gyrus

Question 7

Describe structure of thalamus

Answer 7

Part of diencephalon. In the middle of the brain. Makes up the walls of the third ventricle.

Question 8

Internal medullary lamina

Answer 8

Divides thalamus into anterior, lateral, and medial divisions, which have nuclei that serve different functions.

Question 9

Thalamic reticular nucleus

Answer 9

Covers lateral part of thalamus and serves as a filter (opens and closes). Thalamus=excitatory, Reticular nucleus=inhibitory.

Question 10

Describe function of thalamus

Answer 10

Thalamus receives all sensory information (except smell and unconscious sense) and decides what to do with it. Sensory and motor systems tightly integrated. Thalamus projects to cerebral cortex.

Question 11

Describe functional thalamic groups

Answer 11

Three types of nuclei:

1) Specific or relay: relay information to a specific area in the cortex, which, usually, provides feedback to the same nuclei.
2) Association nuclei: feedback information to nuclei, projection to association areas
3) Non-specific nuclei: projects to broad areas of the cerebral cortex resulting in global effects.

Question 12

Describe the internal capsule and thalamic peduncles

Answer 12

Internal capsule is a bundle of corona radiata by the thalamus (anterior leg, genus, posterior leg). Superior, inferior, anterior, and posterior thalamic peduncles.

Question 13

Describe blood supply of thalamus and stroke implications

Answer 13

(Counter-clockwise from top) Polar a., paramedian a., posterior choroidal a., and thalamogeniculate a. Anterior: language and memory. Medial: arousal and memory. Posterior: vision. Lateral: sensory and motor.