Thalamus HY

Question 1

internal capsule fibers

Answer 1

• brings output of cortex to subcortical sites (to LMNs)

- carries all projections from thalamus to cortex via posterior limb (except for optic)

Question 2

thalamic nuclei

Answer 2

• medial geniculate body
• lateral geniculate body
• VPL (ventroposterolateral)
• VPM (ventroposteromedial)
• VA (ventral anterior)
• VL (ventrolateral)
• anterior
• dorsomedial
• pulvinar

Question 3

medial geniculate body

Answer 3

inf. colliculus –> medial geniculate –> Heschl’s gyrus (A1)

Question 4

lateral geniculate body

Answer 4

optic tract –> lateral geniculate –> visual cortex (V1)

Question 5

VPL

Answer 5

somatosensory pathways (STT, dorsal column)
-sensory info from BODY

STT/DC –> VPL –> sensory cortex

Question 6

VPM

Answer 6

somatosensory pathways (trigeminothalamic tract)
-sensory info from FACE

trigemial (all) –> VPM –> lower end of sensory cortex

Question 7

somatosensory nuclei of thalamus

Answer 7

• VPL

- VPM

Question 8

motor nuclei of thalamus

Answer 8

• VA

- VL

Question 9

VA

Answer 9

• motor system
• basal ganglia

globus pallidus –> VA –> motor, motor association

Question 10

VL

Answer 10

• motor system
• cerebellum

deep nuclei –> VL –> motor, motor association

Question 11

papez circuit

Answer 11

-limbic system

mamillary bodies –> anterior –> cingulate gyrus hippocampus –> mamillary bodies

Question 12

anterior nucleus

Answer 12

• limbic system
• papez circuit

mamillary bodies –> anterior –> cingulate gyrus hippocampus –> mamillary bodies

Question 13

association nuclei

Answer 13

• dorsomedial
• pulvinar

project to association cortex

Question 14

DM

Answer 14

-dorsomedial

amygdala –> DM –> frontal

Question 15

Pulvinar

Answer 15

T/P/O –> Pulvinar –> T/P/O cortices

Question 16

function of the thalamus

Answer 16

modulation of signals before they enter the cortex

–allows for selective attention

Question 17

pure sensory stroke of thalamus

Answer 17

• lacunae in VPL, VPM
• –loss of all sensation in body/face
• infarct due to small vessel disease
• associated with hypertension, DM

typified by:

• microatheroma
• lipohyalinosis

Question 18

thalamic hemorrhage

Answer 18

• spontaneous intracerebral hemorrhage
• associated with hypertension
• involvement of adjacent internal capsule (dominates, adds hemiparesis)
• also sensory involvement

Question 19

common symptoms of thalamic hemorrhage

Answer 19

• numbness, sensory deficits on CONTRAlateral side
• sometimes developing into thalamic pain
• hemiparesis