Proper fasciculus

Proper fasciculus is a term used in neuroanatomy to refer to a bundle of neuronal axons, or nerve fibers, that travel together within the central nervous system. These bundles of axons, which are similar to electrical cables, are responsible for transmitting information throughout the body. The term "proper" is used to distinguish these fasciculi from those that are "improper," or composed of fibers that do not have the same origin and destination.

Structure and Function

The proper fasciculus is composed of myelinated axons, which are wrapped in a fatty substance called myelin that helps to speed up the transmission of electrical signals. These axons originate from the cell bodies of neurons located in the gray matter of the brain or spinal cord, and they carry information to other neurons, muscles, or glands in the body.

The function of the proper fasciculus depends on the specific neurons that it contains. For example, some proper fasciculi are involved in carrying sensory information from the body to the brain, while others are involved in carrying motor commands from the brain to the muscles. Still others are involved in coordinating complex behaviors such as walking or speaking.

Clinical Significance

Damage to a proper fasciculus can result in a variety of neurological symptoms, depending on the specific fibers that are affected. For example, damage to a sensory fasciculus can result in loss of sensation, while damage to a motor fasciculus can result in muscle weakness or paralysis. In some cases, damage to a proper fasciculus can also result in more complex neurological disorders, such as Parkinson's disease or multiple sclerosis.

See Also

• Nervous system
• Neuron
• Myelin
• Gray matter
• Parkinson's disease
• Multiple sclerosis