Nerve fiber bundles are groups of nerve fibers, also known as axons, that are organized together to transmit signals throughout the body. These bundles are essential for communication between different parts of the nervous system, allowing for coordinated responses and functions. They can be found in both the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, which connects the central nervous system to limbs and organs. Each nerve fiber within a bundle is surrounded by a protective layer called myelin, which helps speed up the transmission of electrical signals. The arrangement of these bundles can vary, with some being large and easily identifiable, while others are smaller and more complex. Understanding nerve fiber bundles is crucial for studying conditions that affect the nervous system, such as multiple sclerosis and neuropathy.