Central Nervous System

The Central Nervous System is one of the two main categories of the Nervous System.

It is so named because it receives information from throughout the body, then integrates that information and coordinates and influences action and activities throughout the body.

It works in conjunction with the Peripheral Nervous System. The CNS is found within the dorsal cavity, with the meninges of the Brain in the cranial cavity and in the spinal cavity of the Spinal Cord.

The main function of the CNS is the reception of information, the processing of that information, and often the decision or reaction made to the information.

Along with the peripheral nervous system, the central nervous system works together to control behavior. The CNS is quite complex and the location is extensive.

Within the brain are several areas dedicated to CNS control.

Structure – Brain and Spinal Cord

White and Gray matter

The CNS of the brain is covered by a skull. The CNS is divided in white and grey matter.
1.)  White matter – constitutes Axons and Oliodendrocytes
2.)  Grey matter – constitutes Neurons
Glial Cells – both white and Gray matter have these cells – though white has more.
    –  This type of cell are supporting cells of the CNS
    –  There are different types of this cell
    –   Some act as scaffolding for Neuroblasts  (bergmann glia cells)
    –   Some act macrophages (microglia) and are part of the Immune System

The following is a list – divided into 4 categories:

1.)  Telencephalon

–  Amygdala – helps process memory of “emotional” states
–  Hippocampus – [Front Brain] – short term memory
–  Lateral Ventricles
–  Rhinencephalon – area helps control smell

2.)  Diencephalon

–  Hypothalamus –  Release of several enzymes
–  Pineal gland –  Melatonin production
–  Pituitary gland –  Secretes hormones
–  Thalamus – Process input from the body then relays it to the cerebral cortex
–  Third Ventricle

3.)  Mesencephalon

–  Cerebral peduncle
  Tectum –   Some control of Eye movement, vision, and hearing
–  Pretectum –   Receives input from the eye

4.)  Rhombencephalon

–  Pons –   This is a conduit for information from the cerebellum and the cerebrum, has control in breathing, and a possible role in dreaming
–  Cerebellum –  helps with sensory, coordination, motor control
–  Medulla oblongata –  helps control blood pressure, heart rate, and respiration

The picture to the left depicts the Brain regions of a 4-week old human embryo.

The development of the CNS is quite complex and important.

The brain continues to develop and mature well after birth.

It is believed that the brain is still developing during the first twenty years of life.