DIENCEPHALON

I.   INTRODUCTION

-- diencephalon:

1.  Epithalamus:

2.  Thalamus:

3.  Hypothalamus:

4.  Third Ventricle:

 

 

II.  THIRD VENTRICLE
-- thalamus, hypothalamus, and epithalamus form its  floor, walls and roof

III. EPITHALAMUS

A.  Pineal Gland: appears to regulate the body’s clock
* produces melatonin

IV.  THALAMUS

-- two oval masses of gray matter, covered w/white matter

-- Function: relay point and processing center for all sensory impulses (except olfaction) running to cerebral cortex
*  also acts as sensory information filter

What do you think?  If there were no thalamus, how would this affect the cerebrum’s interpretation of sensory stimuli?

V.   HYPOTHALAMUS

–  its functions include:

1.  Autonomic Nervous System Control Center:

 

 

 

 

 

2.  Endocrine System Control Center:
* endocrine system: secretes hormones into the bloodstream

* hypothalamus produces two hormones which are secreted by the posterior pituitary

* also produces hormones that regulate hormonal secretion of the anterior pituitary

3.  Body Temperature Regulation:

4.  Water and Electrolyte Balance:

* electrolyte: ions and molecules that can carry an electric current

 

* “thirst center”

 

 

5.  Regulation of Hunger/Food Intake:

*  “hunger” or “feeding center”

 

 

*  “satiety center”

6.  Regulation of Sleep-Wake (circadian)Cycles:

7.  Control of Emotional behavior:
* at center of limbic system (“emotional brain”)

 

This structure serves as a center for controlling autonomic activity and endocrine activity:

a. epithalamus

b. third ventricle

c. mesencephalon

d. thalamus

e. hypothalamus

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