An Easy Guide to Neuron Diagrams and Types (2024)

Neurons, also known as nerve cells, send and receive signals from your brain. While neurons have a lot in common with other types of cells, they’re structurally and functionally unique.

Neurons, also known as nerve cells, send and receive signals from your brain. While neurons have a lot in common with other types of cells, they’re structurally and functionally unique.

Specialized projections called axons allow neurons to transmit electrical and chemical signals to other cells. Neurons can also receive these signals via rootlike extensions known as dendrites.

A 2009 study estimated that the human brain houses about 86 billion neurons. The creation of new nerve cells is called neurogenesis. While this process isn’t well understood, we know that it’s much more active when you’re an embryo. However, 2013 evidence suggests that some neurogenesis occurs in adult brains throughout our lives.

As researchers gain insight into both neurons and neurogenesis, many are also working to uncover links to neurodegenerative diseases such as Alzheimer’s and Parkinson’s.

An Easy Guide to Neuron Diagrams and Types (1)Share on Pinterest

Neurons vary in size, shape, and structure depending on their role and location. However, nearly all neurons have three essential parts: a cell body, an axon, and dendrites.

Cell body

Also known as a soma, the cell body is the core section of the neuron. The cell body contains genetic information, maintains the neuron’s structure, and provides energy to drive activities.

Like other cell bodies, a neuron’s soma contains a nucleus and specialized organelles. It’s enclosed by a membrane that both protects it and allows it to interact with its immediate surroundings.


An axon is a long, tail-like structure. It joins the cell body at a specialized junction called the axon hillock. Many axons are insulated with a fatty substance called myelin. Myelin helps axons to conduct an electrical signal.

Neurons usually have one main axon.


Dendrites are fibrous roots that branch out from the cell body. Like antennae, dendrites receive and process signals from the axons of other neurons. Neurons can have more than one set of dendrites, known as dendritic trees.

How many they have generally depends on their role. For instance, Purkinje cells are a special type of neuron found in a part of the brain called the cerebellum. These cells have highly developed dendritic trees which allow them to receive thousands of signals.

Neurons vary in structure, function, and genetic makeup. Given the sheer number of neurons, there are thousands of different types, much like there are thousands of species of living organisms on Earth.

However, there are five major neuron forms. Each combines several elements of the basic neuron shape.

  • Multipolar neurons. These neurons have a single axon and symmetrical dendrites that extend from it. This is the most common form of neuron in the central nervous system.
  • Unipolar neurons. Usually only found in invertebrate species, these neurons have a single axon.
  • Bipolar neurons. Bipolar neurons have two extensions extending from the cell body. At the end of one side is the axon, and the dendrites are on the other side. These types of neurons are mostly found in the retina of the eye. But they can also be found in parts of the nervous system that help the nose and ear function.
  • Pyramidal neurons. These neurons have one axon but several dendrites to form a pyramid type shape. These are the largest neuron cells and are mostly found in the cortex. The cortex is the part of the brain responsible for conscious thoughts.
  • Purkinje neurons. Purkinje neurons have multiple dendrites that fan out from the cell body. These neurons are inhibitory neurons, meaning they release neurotransmitters that keep other neurons from firing.

In terms of function, scientists classify neurons into three broad types: sensory, motor, and interneurons.

Sensory neurons

Sensory neurons help you:

  • taste
  • smell
  • hear
  • see
  • feel things around you

Sensory neurons are triggered by physical and chemical inputs from your environment. Sound, touch, heat, and light are physical inputs. Smell and taste are chemical inputs.

For example, stepping on hot sand activates sensory neurons in the soles of your feet. Those neurons send a message to your brain, which makes you aware of the heat.

Motor neurons

Motor neurons play a role in movement, including voluntary and involuntary movements. These neurons allow the brain and spinal cord to communicate with muscles, organs, and glands all over the body.

There are two types of motor neurons: lower and upper. Lower motor neurons carry signals from the spinal cord to the smooth muscles and skeletal muscles. Upper motor neurons carry signals between your brain and spinal cord.

When you eat, for instance, lower motor neurons in your spinal cord send signals to the smooth muscles in your esophagus, stomach, and intestines. These muscles contract, which allows food to move through your digestive tract.


Interneurons are neural intermediaries found in your brain and spinal cord. They’re the most common type of neuron. They pass signals from sensory neurons and other interneurons to motor neurons and other interneurons. Often, they form complex circuits that help you to react to external stimuli.

For instance, when you touch something sharp like a cactus, sensory neurons in your fingertips send a signal to interneurons in your spinal cord. Some interneurons pass the signal on to motor neurons in your hand, which allows you to move your hand away. Other interneurons send a signal to the pain center in your brain, and you experience pain.

Neurons send signals using action potentials. An action potential is a shift in the neuron’s potential electric energy caused by the flow of charged particles in and out of the membrane of the neuron. When an action potential is generated, it’s carried along the axon to a presynaptic ending.

Action potentials can trigger both chemical and electrical synapses. Synapses are locations where neurons can pass these electrical and chemical messages between them. Synapses are made up of a presynaptic ending, a synaptic cleft, and a postsynaptic ending.

Chemical synapses

In a chemical synapse, the neuron releases of chemical messengers called neurotransmitters. These molecules cross the synaptic cleft and bind to receptors in the postsynaptic ending of a dendrite.

Neurotransmitters can trigger a response in the postsynaptic neuron, causing it to generate an action potential of its own. Alternatively, they can prevent activity in the postsynaptic neuron. In that case, the postsynaptic neuron doesn’t generate an action potential.

Electrical synapses

Electrical synapses can only excite. These synapses form when two neurons are connected by a gap junction. This gap is much smaller than a chemical synapse and is made up of ion channels that help transmit a positive electrical signal.

Because of the way these signals travel, signals move much faster across electrical synapses than chemical synapses. However, these signals can diminish from one neuron to the next. This makes them less effective at transmitting repeated signals.

While research has advanced our understanding of neurons in the last century, there’s still much we don’t understand.

For instance, until recently, researchers believed that neuron creation occurred in adults in a region of the brain called the hippocampus. The hippocampus is involved in memory and learning.

But a 2018 study found that the production of neurons in the hippocampus actually drops after birth. This means that virtually no new neurons are created there by adulthood.

Experts considered this discovery a setback in terms of using neurogenesis to treat diseases like Alzheimer’s and Parkinson’s. These conditions are both the result of neuron damage and death.

There is still hope, though, that neural stem cells can be used to make new neurons. Neural stem cells can produce new neurons, according to the National Institute of Neurological Disorders and Stroke. But researchers are still trying to figure out the best way to use these stem cells to produce specific types of neurons in the laboratory setting.

If this can be done, these nerve cells could be created to replace those that are lost through age, damage, and disease.

Ongoing clinical trials

Many clinical trials are currently underway to test the use of newly created neural cells. For example, this one targets people who have had an ischemic stroke.

Also, a 2019 study used fluorescent probes to observe real-time activity in the nerve cells of mice. This technology could be used to help map brain activity, uncover the problems that lead to neurological disorders, and advance the field of artificial intelligence.

Educational resources

Want to see how much you learned today? Use the resources below to quiz yourself (or your students) on the anatomy and different types of neurons.

  • Anatomy of a Neuron study guide
  • Anatomy of a Neuron quiz
  • Types of Neurons study guide
  • Types of Neurons quiz
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Nervous system cells are called neurons. They have three distinct parts, including a cell body, axon, and dendrites. These parts help them to send and receive chemical and electrical signals.

While there are billions of neurons and thousands of varieties of neurons, they can be classified into three basic groups based on function. These are motor neurons, sensory neurons, and interneurons.

There’s still a lot we don’t know about neurons and the role they play in the development of certain brain conditions. But many research projects and clinical trials are underway to try and find those answers.

An Easy Guide to Neuron Diagrams and Types (2024)


What are the 3 main types of neurons? ›

Based on their roles, the neurons found in the human nervous system can be divided into three classes: sensory neurons, motor neurons, and interneurons.

What are the types and structure of a neuron? ›

A neuron has three main parts: dendrites, an axon, and a cell body or soma (see image below), which can be represented as the branches, roots and trunk of a tree, respectively. A dendrite (tree branch) is where a neuron receives input from other cells.

What is the simplest neuron model? ›

In the field of neural networks and deep learning, the simplest neuron model we could use is perceptron. Which is the sum of weights and variables multiplication goes into a non-linear function such as sigmoid-function. The output of a perceptron could be 1 or 0.

What is the basic layout of a neuron? ›

All neurons have three different parts – dendrites, cell body and axon. The neuron structure is specially adapted to carry messages over large distances in the body quickly in the form of electrical signals.

What are the 5 functions of a neuron? ›

Conduction of Nerve Impulses 2. Ion Gradients across the Membrane 3. Initiation of the Action Potential 4. Conduction of the Action Potential 5.

How many different types of neurons are there? ›

There are three kinds of neurons: Sensory neurons carry information from the sense organs (such as the eyes and ears) to the brain. Motor neurons control voluntary muscle activity, such as walking and talking, and carry messages from nerve cells in the brain to the muscles.

What are the most common types of neurons? ›

Interneurons. Interneurons are neural intermediaries found in your brain and spinal cord. They're the most common type of neuron. They pass signals from sensory neurons and other interneurons to motor neurons and other interneurons.

What are synapses called? ›

synapse, also called neuronal junction, the site of transmission of electric nerve impulses between two nerve cells (neurons) or between a neuron and a gland or muscle cell (effector). A synaptic connection between a neuron and a muscle cell is called a neuromuscular junction.

What are the parts of the neuron and its function? ›

The main function of the neurons is to pass the receiving information and send appropriate signals to the rest parts of the body. The signals received are in the form of electrical signals. Neuron comprises of dendrite, axon and cell body. Dendrites receives messages from the surrounding and sends it to the cell body.

What is the difference between a nerve and a neuron? ›

Neurons are specialized to transmit information throughout the body. Whereas nerve is a whitish fibre or bundle of fibres in the body made up of number of neuron cells that transmits impulses of sensation to the brain or spinal cord, and impulses from these to the muscles and organs.

How many neurons are in the brain? ›

There are approximately 100 billion neurons in a mature human brain. [3] The naturally occurring neuronal cell death occurs prenatally, and elimination of about 50% of unwarranted connections among neurons occurs postnatally.

What does an axon do? ›

From the broadest perspective, the function of axons is to carry electrical impulses that are the means of communication within the brain and between the brain and the rest of the body.

What are the different types of neurons and their names? ›

Receptor (sensory) neurons: makes up sensory nerves that receive stimuli. Effector (motor) neurons: makes up the motor nerves that take and execute commands received from CNS. Intermediate (relay) neurons: present in the brain and spinal cord and interconnect these parts.

How to draw a neural network diagram? ›

You want to think about how many inputs (or data points) you want for each node for each layer. The rule of thumb for drawing a neural network diagram is to use five inputs for every node and keep each node within a circle. Load your dataset into your favorite software.

How to do a neuron project? ›

Take a chart paper and draw an outline of a neuron with dendrites, axons and a cell body with a nucleus. Take a piece of play dough and make a circular-shaped structure. Paste it at the center of the chart paper as a cell body of a neuron.

How do I make neurons? ›

Factors that encourage neurogenesis include:
  1. Learning new skills.
  2. Exercise.
  3. Sex.
  4. Intermittent fasting.
  5. Calorie restriction.
  6. Caffeine.
  7. Resveratrol (found in red wine)
  8. Curcumin (found in turmeric)
May 23, 2021

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