Diencephalon

Question 1

Parts of diencephalon

Answer 1

Hypothalamus, thalamus, geniculate bodies (medial & lateral), subthalamus, epithalamus

Question 2

laminae medullares in thalamus

Answer 2

plates of white matter that separate thalamic nuclei

Question 3

Groups of nuclei in thalamus

Answer 3

anterior:
- nuclei anteriores thalami

medial-dorsal:
- nucleus mediodorsalis

lateral:
- nucleus ventralis anterior, nucleus ventralis lateralis
- nucleus ventralis posterolateralis, nucleus ventralis posteromedialis
- nuclei pulvinares
- corpus geniculatum laterale
- corpus geniculatum mediale

Question 4

Nuclei anteriores thalami

Answer 4

afferent fibers from corpus mamillare (tractus mamillo-thalamicus)

efferent fibers into gyrus cinguli

connects different parts of limbic system
regulation of emotions and memory

Question 5

Nucleus mediodorsalis (MD)

Answer 5

afferent fibers from corpus amygdaloideum

efferent fibers to prefrontal cortex (part of limbic system)

damage causes memory loss, decreases intellectual capacity

Question 6

Lateral thalamic nuclei

Answer 6

nucleus ventralis anterior & nucleus ventralis posterior, VA & VL

nucleus ventralis posterolateralis & nucleus ventralis posteromedialis, VPL & VPM

nuclei pulvinares

corpus geniculatum laterale

corpus geniculatum mediale

Question 7

Thalamus: nucleus ventralis anterior (VA) & nucleus ventralis posterior (VP) of thalamus

Answer 7

afferent fibers from subcortical motor centers (corpus pallidus, substantia nigra, cerebellum)

efferent fibers to premotor and motor cortex

initiation of movement, control of muscle tone
part of extrapyramidal system

Question 8

subcortical motor centers

Answer 8

corpus pallidus, substantia nigra, cerebellum

Question 9

Thalamus: nucleus ventralis posterolateralis (VPL) & nucleus medialis posteromedialis (VPM)

Answer 9

recieve conscious sensory impulses (touch, pain, temperature, taste)

Question 10

Nuclei pulvinares

Answer 10

afferent fibers from corpus geniculatum laterale (et mediale?), colliculus superior and visual association cortical areas

efferent fibers back to visual association cortical areas

regulation of visual attention

Question 11

Corpus geniculatum laterale

Answer 11

afferents via tractus opticus

efferents to primary visual cortex (Brodmann area 17)

interneurons of visual pathway
subcortical visual center

Question 12

Corpus geniculatum mediale

Answer 12

afferents from lemniscus lateralis

efferents to primary auditory cortex (Brodmann areas 41,42)

interneurons of hearing pathway
subcortical auditory center

Question 13

Subthalamus - structure and contents

Answer 13

Below thalamus, separated by sulcus hypothalamicus

Contains nucleus subthalamicus

Question 14

Nucleus subthalamicus

Answer 14

part of extrapyramidal system (controls voluntary movement of limbs)
part of basal nuclei
dorsally to substantia nigra
interconnected with globus pallidus

Question 15

Epithalamus

Answer 15

pineal gland & additional structures:

habenula
trigonum habelunare - in the middle of both thalamus
commissura habelunarum - formed by striae medullares running between superior and medial surfaces of thalamus and partly crossing to the other side

Question 16

Pineal gland

Answer 16

secretes seratonin, norepinephrine and melatonin (makes melatonin from seratonin)

information from visual pathway influences intensity of melatonin synthesis, biological rhythm regulator/cicardian clock

influences development of telencephalon, intellectual ability, proportional development of the body and inhibits maturation of genitals before puberty, responsible for skin pigmentation

Question 17

subcortical visual centers

Answer 17

pulvinar, corpus geniculatum laterale, colliculus superior

Question 18

Hypothalamus - contents

Answer 18

Mamillary bodies (corpus mamillare) : subcortical center of smell

Neurohypophysis : regulates action of all endocrine organs with adenohypophysis (secretes hormones produced in hypothalamus aka oxytocin & ADH), lies in fossa hypophysialis (sella turcica), connected to base of brain via infundibulum

Optic chiasma : crossed medial and uncrossed lateral fibers of CN2 (optic nerve)

Optic tract : fibers of optic nerve from both eyes, terminates in subcortical visual centers

Tuber cinereum : tuberal nuclei, secrete histamine in brain, helps to regulate cicardian cycle

Question 19

Hypothalamus - functions

Answer 19

Highest center of autonomic nervous system

Links nervous system to endocrine system via pituitary gland
secretes neurohormones (hypothalamic-releasing hormones) that stimulate or inhibit secretion from pituitary (adenohypophysis)

Hypothalamus controls body temperature, hunger, thirst, emotions (? at least anger), cicardian cycle etc.

Question 20

Tractus hypothalamicospinalis

Answer 20

axons of hypothalamic nuclei that pass to PARASYMPATHETIC NUCLEI OF BRAIN & SC –> provide control of hypothalamus over autonomical functions

Question 21

ventriculus tertius - anterior border

Answer 21

Lamina terminalis: thin plate from optic chiasma to rostrum corporis callosi

Columnae fornicis

Comissura cerebri anterior: in front of columnae fornicis, bundle of fibers connecting olfactory bulb and olfactory cortex

Recessus supraopticus: lower part of anterior wall

Question 22

ventriculus tertius - posterior border

Answer 22

epiphysis

commissura habenularum

commissura cerebri posterior: band of nerve fibers beneath pineal gland, connecting both sides of midbrain

Question 23

ventriculus tertius - superior border

Answer 23

tela choroidea: duplication of pia mater encephali

plexus choroideus: produces CSF

Question 24

ventriculus tertius - communications

Answer 24

aqueductus cerebri - with 4th ventricle posteriorly

foramina interventricularia  (2) - with lateral ventricles anteriorly
foramen interventriculare is bordered by columnae fornicis (anterior) and tuberculum anterius thalami (posterior)