1. and its functions

3. Nuclear groups: ANTERIOR / PREOPTIC GROUP PREOPTIC n PARAVENTRICULAR n ANTERIOR n SUPRAOPTIC n SUPRACHIASMATIC n MIDDLE / TUBERAL GROUP DORSOMEDIAL n VETROMEDIAL n LATERAL n ARCUATE/ TUBERAL n POSTERIOR / MAMILLARY GROUP POSTERIOR hypothalamic nuclei MAMILLARY, SUPRAMAMILLARY BODY

4. Regulates ant. pit. hrs (discrete area) Secretion of Post. Pit. hrs (SON, PVN) Controls adrenal cortex – CRH –PVN Controls ad. Medulla – catecholamine (emotions) – P, L, A nucleus

5. Regulation of food intake – VMN (Satiety centre) Lateral Nucleus (Feeding Centre)

6. Temperature regulation PON (Heat loss) Post Hypothalamus (Heat gain)

7. Thirst centre – OVLT, SFO Regulation of water intake – SOP & PVN

8. Role in sleep & wakefulness – Post Hypothalamus Circadian rhythm - SCN

9. Influences memory, emotion motivation behaviours – VMN & Lateral nucleus stronger stimuli on Lateral nucleus activates Punishment centre Reward centre – Medial Forebrain Bundle, (especially) Ventromedial hypothalamus & Lateral (weaker +)

10. Anterior group PARA- VENTRICULAR nucleus (PVN) Regulates water balance Synthesis & release of ADH - Vasopressin & Oxytocin CRH,TRH, Somatostatin release SIADH, Central Diabetes Insipidus, Hypertension SUPRAOPTIC nucleus (SON) Regulates Water Balance Synthesis & Release of ADH - Vasopressin & Oxytocin SIADH, Central Diabetes Insipidus, Hypertension, addictions SUPRACHIASM ATIC nucleus (SCN ) Biological clock Circadian rhythm = 24h light–dark cycle receives visual input from retina--optic tract Abolishes circadian rhythm, insomnia, narcolepsy PREOPTIC nucleus (PON) Regulates release of GnRH --- Ant Pit---- Androgens & Oestrogens Regulates Sexual behaviour (medial PON in females) thermoregulation Before puberty : arrest of sexual development After Puberty : amenorrhea, impotence, infertility ANTERIOR nucleus (AN) THERMAL REGULATION - Senses increase in Body temp. Response : heat dissipation. Stimulates : PNS Destruction leads to HYPETYHERMIA

11. MIDDLE or TUBERAL GROUP NUCLEIFUNCTIONLESION EFFECTS DORSOMEDIAL nucleus Stimulation results in obesity and savage behaviour Destruction results in starvation – FATAL ANOREXIA NERVOSA VETROMEDIAL nucleus Satiety Centre - cessation of eating destruction leads to HYPERPHAGIA - obesity & savage behaviour HYPOTHALAMIC OBESIT Y LATERAL hypothalamic area Feeding centre General sympathetic activation – piloerction, rise in BP, sweating, pupillary dilation, Destruction results in starvation – FATAL ANOREXIA NERVOSA ARCUATE/ TUBERAL nucleus produces hypothalamic releasing hormones Contains DOPA-ergic neurons that inhibit prolactin release (PIF )

12. Posterior or Mammillary group POSTERIOR nucleus Thermal regulation (conservation of heat) Stimulates SNS Inability to thermo regulate MAMILLARY BODY / nuclei Receives input form limbic system & hippocampus Mammothalamic tract from thalamus Memory Wernicke’s encephalopathy Korsakoff psychosis (COAT n RACK)

13. Thank u