Diencephalon

Question 1

the main structure of the epithalamus? Function? Composition

Answer 1

pineal gland. Antigonadotrophic in children. Circadian rhythm in adult. More melotonin made when its dark, stimulating symp NS and suppressing brain function. Pinealocytes (nervous and endocrine)

Question 2

what are the reciprocal connections of the thalamus and cortex called

Answer 2

thalamocortical and corticothalamic

Question 3

main general function of thalamus. exceptions

Answer 3

relay center. All sensory pathways except olfactory.

Question 4

what subdivides the thalamus and into what is it subdivided

Answer 4

the internal medullary lamina. Lateral (including VPL, VPM), medial, anterior, and meta (MG and LG)

Question 5

function of vpl, vpm, vl

Answer 5

somatic sensation from body; from head; input from basal ganglia

Question 6

function of the anterior nuclear group

Answer 6

relay for limbic system. input from mammillary body of hypothal. to cingulate gyrus

Question 7

Contents of metathalamus and their functions

Answer 7

Medial Geniculate- auditory from inferior colliculus and brachium to heschels. Lateral Geniculate- visual from retina to optic radiations and calcarine sulcus

Question 8

Explain reticular nucleus: path of neurons, functions

Answer 8

Form inhibitory synapses on thalamocortical neurons (dont project into cortex). When activated, cause burst mode (daydreaming and non-REM sleep), seen as sleep spindles

Question 9

what does the massa intermedia consist of

Answer 9

gray matter of midline nuclei

Question 10

Thalamic syndrome of Dejerine-Roussy

Answer 10

Occlusion of branch of PCA supplying VPM and VPL. Initially: contralat hemisensory loss in head and body. Later: dysesthesia, intractable pain, emotional instability

Question 11

subthalamic nucleus stroke

Answer 11

hamiballismus (hyperkinetic disorder)

Question 12

divisions of hypothalamus

Answer 12

three longitudinal zones: periventricular, medial, lateral. Four regions: preoptic, anterior, middle, posterior

Question 13

three fiber bundles of hypothalamus

Answer 13

stria terminalis (amygdala to fugus), forniz, mammillothalamic tract

Question 14

function of hypothalamus

Answer 14

maintain homeostasis (hunger/satiety, ADH, body temp), motivated behaviors (reproduction), circadian rhythms (suprachiasmatic nucleus is relay from retinal to pineal gland)