What are neurotransmitters?

Neurotransmitters are chemical messengers in the body. Their job is to transmit signals from nerve cells to target cells. These target cells may be in muscles, glands, or other nerves.

The brain needs neurotransmitters to regulate many necessary functions, including:

heart rate


sleep cycles





muscle movement

The nervous system controls the body’s organs, psychological functions, and physical functions. Nerve cells, also known as neurons, and their neurotransmitters play important roles in this system.

Nerve cells fire nerve impulses. They do this by releasing neurotransmitters, which are chemicals that carry signals to other cells.

Neurotransmitters relay their messages by traveling between cells and attaching to specific receptors on target cells.

Each neurotransmitter attaches to a different receptor — for example, dopamine molecules attach to dopamine receptors. When they attach, this triggers action in the target cells.

After neurotransmitters deliver their messages, the body breaks down or recycles them.

Key types of neurotransmitters

Experts have identified more than 100 neurotransmitters to date.

Neurotransmitters have different types of action:

  • Excitatory neurotransmitters encourage a target cell to take action.

  • Inhibitory neurotransmitters decrease the chances of the target cell taking action. In some cases, these neurotransmitters have a relaxation-like effect.

  • Modulatory neurotransmitters can send messages to many neurons at the same time. They also communicate with other neurotransmitters.

Some neurotransmitters can carry out various functions, depending on the type of receptor that they are connecting to.

The following sections describe some of the best-known neurotransmitters.

Acetylcholine (EAM = 300Hz)

Acetylcholine triggers muscle contractions, stimulates some hormones, and controls the heartbeat. It also plays an important role in brain function and memory. It is an excitatory neurotransmitter.

Low levels of acetylcholine are linked with issues with memory and thinking, such as those that affect people with Alzheimer’s disease. Some Alzheimer’s medications help slow the breakdown of acetylcholine in the body, and this can help control some symptoms, such as memory loss.

Having high levels of acetylcholine can cause too much muscle contraction. This can lead to seizures, spasms, and other health issues.

The nutrient choline, wh