A neuron, also known as a nerve cell or neurone, is the fundamental unit of the brain and nervous system. These specialized cells are responsible for receiving sensory input, transmitting information throughout the body, and enabling everything from breathing and thinking to movement and speech.
What Neurons Do
Neurons are excitable cells that communicate by firing electrical signals called action potentials across a neural network. This intricate network allows for rapid and efficient information processing throughout the body. Think of them as tiny messengers, constantly sending and receiving messages to coordinate bodily functions.
- Sensory Input: Neurons receive information from the environment through sensory receptors (e.g., light, sound, touch).
- Information Processing: This sensory input, along with information from other neurons, is processed within the neuron.
- Signal Transmission: The processed information is then transmitted to other neurons, muscles, or glands via electrical and chemical signals.
Neuron Structure and Types
While the specific structure can vary, a typical neuron includes:
- Soma (Cell Body): Contains the nucleus and other organelles.
- Dendrites: Branch-like extensions that receive signals from other neurons.
- Axon: A long, slender projection that transmits signals to other neurons.
- Synapse: The junction between two neurons where communication occurs via neurotransmitters.
There are many different types of neurons, each with specialized functions, categorized by their structure and location within the nervous system. Examples include motor neurons that control muscle movement and sensory neurons that relay information from the senses.
Neurons and the Brain
Neurons make up approximately 10 percent of the brain; the rest consists of glial cells and astrocytes that support and nourish neurons. The complex interactions between these cells are essential for brain function. In conditions like Alzheimer's disease, neuron damage and dysfunction play a significant role in cognitive decline. Constant communication between neighboring brain cells via neurons is key to healthy brain function.
References: Information in this response is synthesized from multiple sources, including those provided: the National Institute of Neurological Disorders and Stroke (NINDS), the Queensland Brain Institute, Cell Press, Wikipedia, Healthline, Medical News Today, StatPearls, PubMed Central, and the National Institute on Aging (NIA).
