3/10 Diencephalon

DIENCEPHALONShannon Ng

WHAT’S THE DIENCEPHALON?The diencephalon is the region of the

vertebrate neural tube which gives rise to the posterior forebrain structures.

neural tube- the embryo’s precursor to the central nervous system

In development, the forebrain develops from the prosencephalon, the most anterior vesicle of the neural tube which later forms both the diencephalon and the telencephalon. In adults, the diencephalon appears at the upper end of the brain stem, situated between the cerebrum and the brain stem. It is made up of four distinct components: the thalamus, the subthalamus, the hypothalamus, and the epithalamus.

The diencephalon relays sensory information between the brain regions and controls many autonomic functions of the peripheral nervous system.

It also connects structures of the endocrine system with the nervous system and works in conjunction with limbic system structures to generate emotions and memories.

LOCATION Directionally, the diencephalon is

situated between the cerebral hemispheres, superior to the midbrain.

FUNCTIONS directing sense impulses throughout the

body autonomic function control endocrine function control motor function control homeostasis hearing, vision, smell, and taste touch perception

STRUCTURES OF THE DIENCEPHALON hypothalamus thalamus epithalamus (including the pineal gland) subthalamus

HYPOTHALAMUS This is the portion of the brain that

contains a number of nuclei with a variety of functions. One of the important functions of the hypothalamus is to link the nervous system to the endocrine system via the pituitary gland.

pituitary gland or hypophysis – an endocrine gland and is at the base of the brain

endocrine system – a system of glands which secretes a type of hormone directly to the bloodstream

THALAMUS This is a midline paired symmetrical

structure within the brains of vertebrates, including humans. Its functions includes relaying sensation, spatial sense, and motor signals.

EPITHALAMUS This is the dorsal posterior segment of

the diencephalon. Its function is the connection between the limbic system to the other parts of the brain.

limbic system- a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex, and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction

SUBTHALAMUS It is a part of the diencephalon that

encompasses globus pallidus, which is topographically part of the telencephalon.

globus pallidus (paleostriatum)- a sub-cortical part of the brain which is part of the telencephalon

telencephalon- cerebrum

Thank You!

Sources:en.wikipedia.org

biology.about.com