- most common location for hypothalamic brain tumors

- disrupts parasympathetics to body (unopposed sympathetics)

- disrupts visual function (bitemporal hemianopsia)

Anterior Commisure/Lamina Terminalis

(anterior to hypothalamus)

- mammilary bodies adjacent to mesencephalon

- disruption causes confusion, loss of memory consolidation (short-term to long-term)

- also disrupts limbic and emotional function

Posterior to Hypothalamus

- surrounds infundibulum

- raised portion of hypothalamus

Tuber cinereum

- receive projections from hippocampus via fornix

- send to anterior thalamic nucleus

Mammilary bodies

- "sleep center"

- receives olfactory information

- input from amygdala and septal nuclei

- prevents overheating

- stimulation increases parasympathetic activity

Anterior hypothalamic nucleus

- regulates sexual function

- release LHRH

- destruction of this area results in Kallman's syndrome (no gonads)

Preoptic area

(in anterior hypothalamic nucleus)

- produces mostly vasopressin (ADH)

Supraoptic nucleus

- produces mostly oxytocin

Paraventricular nucleus

- role in circadian rhythms

- release GnRH and GH during sleep

- recieves direct projections from retina

Suprachiasmatic nucleus

- stalk of pituitary gland

- surrounded by tuber cinereum

- site of release of inhibiting/releasing factors

- dopamine (not a peptide)

Infundibulum

- stimulation induces eating

- lesion causes starvation and not drinking (adipsia)

Lateral hypothalamus

- Leptin binds to Ob receptors here to inhibit eating

Medial hypothalamus

- stimulation increases sympathetic activity

- conserves heat (shivering)

- causes waking (reticular activation)

- "warm butt"

Posterior hypothalamus

- taste and blood chemoreceptors

- monitors the relative concentrations of oxygen and carbon dioxide

Solitary tract

- pain and reticular function

- input into hypothalamus

- from PAQ, reticular formation, dorsal columns and medial lemniscal system

Dorsal Longitudinal Fasciculus

- Dorsal Longitudinal fasciculus makes this

B-endorphin

- projections from lateral and preoptic hypothalamus to the habenula

Stria medullaris

- can monitor blood volume or hormones in the blood (osmolarity and angiotensin II)

Subfornical organs

- located in IV ventricle and thought to monitor toxins in blood, produce vomiting

Area Postrema

- part of lamina terminalis

- senses plasma osmolarity

- reduced blood-brain barrier

Organum vasculosum

- petechial hemorrhage in the brain and retina is a clear indication for this

Child abuse

- hemorrhage that destroys the pituitary gland associated with tumors

- vision problems, headache, drowsiness, confusion, coma

Pituitary apoplexy