What Are Neurons?

Table of Contents
View All
Table of Contents

Neurons are information carrier cells within the central nervous system (CNS) and peripheral nervous system (PNS). The CNS includes the brain and spinal cord, while the PNS includes neurons throughout the rest of the body. Neurons use electrical impulses and chemical signals, called neurotransmitters, to communicate information throughout the CNS and PNS.

If you've ever wondered how our minds and bodies collaborate, allowing us to consciously move, feel, and think, it all begins with neurons. This article provides an overview of neurons, their structure, types, and how they work.

Neurons

zf L / Getty Images

Neuron Structure

Most neurons have three parts: a cell body, an axon, and dendrites.

The Cell Body

The cell body of neuron contains the nucleus. The nucleus contains our genetic information. It also includes the cytoplasm, which is the fluid that houses the majority of cellular material within the neuron.

Axons

An axon is a long, narrow connecting line that snakes away from the cell body to send electrical impulses to other neurons. Through these impulses, axons are responsible for the active transmission of information throughout the entire body.

Axons look like long tails. They branch into many smaller branches that reach towards the axons of other neurons.

Dendrites

Dendrites also extend from the neuron cell body, but they are responsible for receiving messages from other neurons.

Dendrites, which look like tree branches, collect information to bring back to the neuron. Each dendrite's end is a contact point that allows one neuron to connect with another. These contact points are called synapses. Dendrites have many of them.

Glial Cells

Neurons rely on another type of cell called glial cells. Glial cells are sometimes referred to as "nerve glue" because they provide connectivity between neurons to allow for the movement of information. They aid in the transport of nutrients, hormones, and neurotransmitters.

Types of Neurons

There are different types of neurons, including motor, sensory, and interneurons.

Motor Neurons

Motor neurons transmit electrical impulses and information from the CNS to muscles in the body. Motor neurons control all of our body movements.

There are two main motor neurons subtypes:

  • Upper motor neurons: Send data from the brain to the lower motor neurons
  • Lower motor neurons: Send data from the upper motor neurons to muscles in the body

Sensory Neurons

Sensory neurons are neurons that allow us to feel sensation. For example, if you stub your toe, sensory neurons will send chemical and electrical impulses back through the nervous system to tell your brain that you feel pain in your toe.

Sensory neurons can be activated physically, such as feeling touch, or chemically, such as tasting a piece of cake. All five of our senses—sound, sight, touch, smell, and taste—are impacted by sensory neurons.

Interneurons

Interneurons are nerve cells that connect between motor neurons and sensory neurons. Interneurons can also send information to and from other interneurons.

How Do Neurons Work?

Neurons work by sending chemicals, called neurotransmitters, across a small area between the axon of one neuron and the dendrite of another. This tiny space that allows for information exchange is called a synapse.

Neurons also allow the CNS and the PNS to report information back to each other instantaneously and constantly. This information exchange enables us to think, talk, feel, move, and do every other thing that our bodies are capable of doing.

Neuron Functions

A neuron's function involves sending electrical impulses and chemical signals to and from the brain.

Neurons complete this task using a process called "action potential." Action potential is the quick flow of electrical voltage from the neuron down the axon. This voltage allows information to be transmitted from neuron to neuron all over the body.

Summary

Neurons carry signals throughout the central and peripheral nervous systems. Their function is to send electrical impulses and chemical signals to and from the brain.

Most neurons have three parts, including a cell body, which contains the nucleus and the cytoplasm, an axon, which transmits information away from the nucleus, and dendrites, which receive messages from other neurons.

The main types of neurons include motor neurons, which transmit information to our muscles, sensory neurons, which transmit information to enable our senses, and interneurons, which aid transmission between motor and sensory neurons.

A Word From Verywell

Neurons are essential to human life. They allow our body and brain to communicate and enable us to think, feel, and move. Additional research can help us understand the complexity behind how neurons work.

Frequently Asked Questions

  • What is a neuron?

    Neurons are information carrier cells within the central nervous system (CNS) and peripheral nervous system (PNS). They work by allowing the CNS and the PNS to report information to each other, which allows us to think, talk, feel, and move.

  • Where are neurons located in the body?

    Neurons are located in the brain and spinal cord, which are organs of the CNS. Neurons are also located throughout the rest of the body in the PNS.

  • What are the different types of neurons?

    There are three main types of neurons:

    • Motor neurons make the connection between the brain and muscles throughout the body. These neurons transmit electrical impulses containing information to skeletal muscles and smooth muscles. Motor neurons control all of our body movement.
    • Sensory neurons are neurons that let us feel sensation. If you burn your hand, sensory neurons will send chemical and electrical impulses back through the nervous system to let your brain know that you feel pain in your hand.
    • Interneurons are the nerve cells that connect motor neurons to other motor neurons and sensory neurons to other sensory neurons.
Was this page helpful?
4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Neurological Disorders and Stroke. Brain basics: the life and death of a neuron.

  2. Faber DS, Pereda AE. Two forms of electrical transmission between neurons. Front Mol Neurosci. 2018;11:427. doi:10.3389/fnmol.2018.00427

  3. Argente-Arizón P, Guerra-Cantera S, Garcia-Segura LM, Argente J, Chowen JA. Glial cells and energy balance. J Mol Endocrinol. 2017;58(1):R59-R71. doi:10.1530/JME-16-0182

  4. Columbia University Motor Neuron Center. About motor neurons.