The hypothalamus and limbic system help regulate basic physiological needs like blood pressure, body temperature, energy metabolism, reproduction, and stress responses. Specifically, the hypothalamus controls the pituitary gland to regulate these functions. It is connected to the limbic system, brainstem, and spinal cord. The limbic system includes structures like the hippocampus, amygdala, and fornix that are involved in emotion and memory.

1. Hypothalmamus and limbic system
By
Dr Manah Chandra Changmai

2. Hypothalamus
The hypothalamus consists of only 4 cm3 of neural tissue, or
0.3% of the total brain.
The hypothalamus extends from the lamina terminalis to a vertical
plane posterior to the mammillary bodies, and from the
hypothalamic sulcus to the base of the brain beneath the third
ventricle.
Hypothalamus

3.  It lies beneath the thalamus and anterior to
the tegmental part of the subthalamus and
the mesencephalic tegmentum
Relations
 Anteriorly:
Extends upto lamina terminalis and merges with
olfactory Structures.
 Posteriorly :
Merges with ventral thalamus and through it to
the Tegmentum of midbrain.
 Medial side:
Forms the wall of the third ventricle below the
levelOf hypothalamic sulcus.
 Laterally :
Contact with the internal capsule
 Inferiorly:
Related to the structures of the third ventricle

4. Pellucidum
Septum pellucidum Hypothalamic sulcus
Hypothalamus
Lamina terminalis
Mamillary body
Choroid plexus
Aqueduct
Interventricular foramen

5. Subdivisions of the hypothalamus
Divided into three zones
Periventricular zone Intermediate zone Lateral zone
The periventricular and intermediate zones are often described together
as medial zone

6. The hypothalamus also divide anteropoateriorly into four regions
Preoptic
-Adjoins lamina
terminalis
Supraoptic(chiasmatic)
-Lie above optic chiasma
Tuberal
(infundibulotuberal)
-includes infundibulum
tubercinereum
Mamillary
(posterior)
-consists of
mamillary
body and
area above it)

8. Hypothalamus

10. Hypothalamus and nuclei within them
Medial Zone
(Periventricular and
intermediate)
Lateral Zone
Preoptic region Preoptic nucleus
Supraoptic region Paraventricular nucleus
Periventricular cell grps
Suprachiasmatic nucleus
Intermediate cell group
Suprachiasmatic
nucleus
Tuberal region Dorsimedial nucleus
Ventrimedial nucleus
Arcuate/infundibular nu.
Premamillary nucleus
Lateral tuberal
nucleus
Mamillary or posterior
region
Posterior nucleus Tuberomamillary
nucleus
Mamillary body Mamillary nuclei

11. Hypothalamus

12. Hypothalamus

13. Connections of the hypothalamus
Hypothalamus is concerned with
visceral function
Connected to various parts of limbis
system,reticular formation,autonomic
centres in brainstem and spinal cord.
It also releases secretions into the blood
stream and into CSF.

14. Afferent connections
The hypothalamus recieves visceral(including
Taste) through spinal cord and brainstem.
Afferents from nucleus of tractus solitarius to
hypothalamus carry taste sensation.
Somatic afferents reach through collaterals of
major ascending tract
Afferents from olfactory pathway and limbic
system.
anterior perforated substance,septal nuclei
Amygdaloid complex,hippocampus,piriform
cortex.
Limbic system
Neocortex
Hypothalamus
Thalamus
Ascending
Somatosensory
pathway
Visual input
Visceral centres
In brainstem &
Spinal cord.

15. Cortico-hypothalamic fibres
Hypothalamus receive fibres from the cortex of the frontal lobe
Many fibres relay in the thalamus (medial dorsal
and midline nuclei and reach hypothalamus
through periventricular fibres
Efferent connections
The hypothalamus sends fibres to autonomic
Centres in brain and spinal cord
In brainstem:-Nucleus of solitary tract
-Dorsal nucleus of vagus
-Nucleus ambigus
-Parabrachial nucleus

16. Efferent connections of Hypothalamus
Hypothalamus
Limbic system
-Hippocampus
-septal nuclei
-Amygdaloid complex
Neocortex
Thalamus
-From mamillary
body
Visceral centre in
Brainstem
-nu. Of tractus solitary tract
-Dorsal nu. Of vagus
-nu. Ambogus
-Parabrachial nu.
Spinal cord:Intermediolateral grey
column
Neoendocrine influence
of hypophysis cerebri

17. Control of hypophysis cerebri by hypothalamus
Neurons in some hypothalamic nuclei produce
Bioactive peptides discharged to neighbourhood
Capillaries(neurosecretion)
Control of neurohypophysis(posterior lobe)
-Vasopressin is secreted in supraoptic nuclei
-Oxytocin is secreted in paraventricular nucleus.
-Axons of the paraventricular nucleus descends
Towards the supraoptic nucleus and joins the axon
From supraoptic nucleus as the paraventriculohypo
Physeal tract.

18. Control of hypophysis cerebri by hypothalamus
Axons of paraventriculo-hypophyseal tract
join axons arising from supra-optic nucleus
to form supraoptico-hypophyseal tract.
The axons of supraoptico-hypophyseal tract pass
down into neurohypophysis where they branch
and end in relation to capillaries and release
their secretion.
Together known as
Hypoyhalamo-hypophyseal tract
Paraventicular nucleus
Hypophysis cerebri
Supraoptic
Paraventriculo- nucleus
Hypophyseal tract
Supraoptico-hypophyseal
tract

19. Control of hypophysis cerebri by hypothalamus

20. Control of adenohypophysis by hypothalamus
Hypothalamus control adenohypophysis by
Producing number of releasing factors.
Releasing factors travel through tubero-hypophyseal
tract which recieves fibres
from various nuclei.
Release the factors into the capillaries
The capillaries carry the factors into the
pars anterior of hypophysis cerebri through
hypothalamo-hypophseal portal system.
Paraventricular nucleus
Supra-chiasmatic
nucleus
Hypophysis cerebri
Limbic system
Fibres from
brainstem
Tubero-infundibul
ar tract

22. Limbic system

23. Limbic system
Limbic system,in the past are believed to
play an important role in the control of
visceral activity
The areas of cerebral cortex in the region
are often refereed to as LIMBIC LOBE

24. Areas forming the limbic cortex
Hippocampus (ammon’s horn ) and dentate gyrus
Entorhinal cortex
Gyrus cinguli and paraterminal gyrus
Part of the parahippocampal gyrus
The indisium griseum ( regarded as vestigial part of
limbic cortex)
The amygdaloid nuclei

25. Fibres bundles related to the limbic system
1.Olfactory nerves,tract and striae
2.Fornix
3.Stria terminalis
4.Stria medullaris thalami
5.Diagonal band
6.Anterior commissure
Anterior commissure

26. Amygdaloid nuclear complex
-The region is called amygdaloid body
or amygdala.
-Situated near the temporal pole of cerebral
hemisphere.
-Lie in close relation to anterior end of inferior
horn of lateral ventricle.
-The lower end of stria terminalis lie in relation
to amygdaloid complex.

27. Septal region
-Masses of grey matter lie immediately
anterior to lamina terminalis and the
anterior commissure.
-Continous inferiorly with diagonal
band
-superiorly with indusium griseum.
-Related specially to hippocampus and
to hypothalamus.
Septal region

28. Hippocampal formation
-Develops in relation to medial surface
of cerebral hemisphere
-C shaped in accordance with outline of
body and inferior horn of the ventricle.
-Underdeveloped thin layer of grey matter
lining the upper surface of corpus callosum
is called INDUSIUM GRISEUM
-Dendate gyrus present in relation to inferior
horn of lateral ventricle.

30. Hippocampus

32. Fibre bundles of limbic system
Stria teminalis
-Related to inferior horn and central part of
The lateral ventricle
-It begins in amygdaloid complex and runs
backwards in the roof of the inferior horn
-It terminates near interventricular foramen
and anterior commissure by dividing into
various bundle.

33. Septum pellucidum Fornix
Anterior commissure
-Situated in the anterior wall of the third
ventricle at the upper end of lamina terminalis
The Fornix
-Made up of fibres arising from hippocampus
-Body of the fornix suspended from corpus
callosum by septum pellucidum
-Posteriorly,divides into two crura.
-The crura are interconnected by fibres passing
from one another forming hippocampal
commissure.
Anterior commissure

34. Fornix

35. • The hypothalamus and limbic system helps regulate
five basic physiological needs:
1) Controls blood pressure and electrolyte (drinking and salt
appetite).
2) Regulates body temperature through influence both of the
autonomic nervous system and of brain circuits directing
motivated behavior (e.g. behavior that seeks a warmer or
cooler environment).
3) Regulates energy metabolism through influence on
feeding, digestion, and metabolic rate.
4) Regulates reproduction through hormonal control of
mating, pregnancy and lactation.
5) Directs responses to stress by influencing blood flow to
specific tissues, and by stimulating the secretion of adrenal
stress hormones.

36. Thank you