The hypothalamus I

Hypothalamic nuclei Medial zone nuclei Lateral zone nuclei    1. Pre optic    2. Anterior    3. Supra ...

Hypothalamic nuclei

Medial zone nuclei	Lateral zone nuclei
1. Pre optic    2. Anterior    3. Supra chiasmatic    4. Para ventricular    5. Dorso – medial    6. Ventero – medial    7. Arcuate (Infundibular)    8. Posterior	1. Pre optic    2. Supra chiasmatic    3. Supra optic    4. Lateral    5. Tuberomammilary    6. Lateral tuberal

Position of the hypothalamic nuclei



Hypothalamus receives information via:

1) Nervous connections
2) Blood stream
3) CSF


A. Afferent pathways of the hypothalamus

Pathway	Origin	Destination
Visual fibers	Retina	Supra chiasmatic nucleus
Medial & spinal lemnisci, tractus solitarius & RF	Viscera & somatic structures	Hypothalamic nuclei
Medial forebrain fibers	Olfactory mucus membrane
Auditory fibers	Inner ear
Cortico – hypothalamic fibers	Frontal lobe of the cerebral cortex
Amygdalo – hypothalamic fibers	Amygdaloid nucleus
Thalamo – hypothalamic fibers	Thalamus
Tegmental fibers	Tegmentum of the midbrain
Hippocampo – thalamic fibers (Limbic system)	Hippocampus	Nuclei of mammillary body

B. Efferent pathways of the hypothalamus

Pathway	Origin	Destination
Descending fibers in RF to brainstem & spinal cord	Pre optic, anterior, posterior & lateral nuclei of hypothalamus	Cranio – sacral parasympathetic & thoraco – lumbar sympathetic outflows
Mammillo – thalamic tract	Nuclei of mammillary body	Anterior nucleus of thalamus, relayed to Cingulate gyrus
Mammillo – Tegmental tract		RF in Tegmentum in midbrain
Multiple pathways	Hypothalamic nuclei	Limbic system