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# Neurotransmitter

neu·ro·trans·mit·ter - NOOR-oh-tranz-MIT-er

## Definition

A neurotransmitter is a [chemical messenger](/glossary/hormone) that transmits signals across the synapse (the tiny gap) between nerve cells (neurons), enabling communication throughout the nervous system. When an electrical signal reaches the end of a neuron, it triggers the release of neurotransmitter molecules, which cross the synapse and bind to receptors on the receiving neuron, either exciting it (promoting signal transmission) or inhibiting it (suppressing signal transmission).

There are over 100 identified neurotransmitters, but several play particularly prominent roles in health and disease. Serotonin regulates mood, sleep, appetite, and digestion. Dopamine drives motivation, reward, pleasure, and movement. Norepinephrine manages alertness, attention, and the [stress response](/glossary/stress-response). GABA (gamma-aminobutyric acid) is the primary inhibitory neurotransmitter, promoting calm and reducing anxiety. Glutamate is the primary excitatory neurotransmitter, essential for learning and memory. Acetylcholine controls muscle contraction and is involved in memory and attention.

Neurotransmitter imbalances are implicated in numerous mental health and neurological conditions. Depression has been linked to low [serotonin](/glossary/serotonin) and norepinephrine. [Parkinson's disease](/conditions/parkinsons-disease) involves the loss of [dopamine](/glossary/dopamine)\-producing neurons. Anxiety disorders may involve GABA dysfunction. Many psychiatric medications - including SSRIs, SNRIs, and MAO inhibitors - work by modifying neurotransmitter levels or activity at synapses.

## Also Known As

Chemical messenger Neural signaling molecule 

## Key Facts

-   • Over 100 neurotransmitters have been identified, with serotonin, dopamine, norepinephrine, GABA, glutamate, and acetylcholine being the most clinically significant. 
-   • About 90% of the body's serotonin is produced in the gut, not the brain - highlighting the gut-brain connection. 
-   • Most antidepressants work by increasing the availability of serotonin, norepinephrine, or dopamine at synapses. 
-   • Neurotransmitter function depends on adequate intake of amino acid precursors, B vitamins, iron, magnesium, and other cofactors. 
-   • Exercise increases levels of serotonin, dopamine, norepinephrine, and endorphins - contributing to its antidepressant and anxiolytic effects. 

## How It Relates To Your Health

Understanding neurotransmitters helps explain how psychiatric medications work and why lifestyle factors significantly impact mental health. If you're taking medications for depression, anxiety, [ADHD](/conditions/adhd), or other conditions, knowing which neurotransmitter system they target can help you understand their effects and side effects.

Natural strategies that support healthy neurotransmitter function include regular exercise, adequate sleep, a nutrient-rich diet (particularly [amino acids](/glossary/amino-acid), B vitamins, and [omega-3 fatty acids](/glossary/omega-3-fatty-acids)), stress management, and social connection. These lifestyle factors provide the raw materials and conditions for optimal neurotransmitter production and function.

## Related Terms

[Serotonin](/glossary/serotonin)[Dopamine](/glossary/dopamine)[Norepinephrine](/glossary/norepinephrine)[Endorphins](/glossary/endorphins)[Neuroplasticity](/glossary/neuroplasticity)

## Related Articles

[![How Gut Health Affects Your Mood](https://images.unsplash.com/photo-1512621776951-a57141f2eefd?w=1200&h=630&fit=crop&fm=webp)](/mental-health/gut-health-affects-mood)

[](/mental-health/gut-health-affects-mood)[Mental Health](/mental-health)

### How Gut Health Affects Your Mood

2025-11-10

## Sources

1.  [Neurotransmitters](https://my.clevelandclinic.org/health/articles/22513-neurotransmitters) - Cleveland Clinic
2.  [Neurotransmitters](https://www.ncbi.nlm.nih.gov/books/NBK539901/) - StatPearls / PubMed
3.  [Brain Basics: The Life and Death of a Neuron](https://www.ninds.nih.gov/health-information/educational-resources/brain-basics/brain-basics-life-and-death-neuron) - National Institute of Neurological Disorders and Stroke (NIH)

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