In brief
The brain, spinal cord and nerves. The nervous system lets all parts of the body communicate with each other and reacts to changes outside and inside the body.
- The bowel has its own separate nervous system, the enteric nervous system.
- The hypothalamus releases hormones that help control the pituitary gland, the body's master gland.
- Some nerve messages work automatically, such as the salivary glands producing saliva when you eat.
How it works
The brain and spinal cord make up the central nervous system, and the nerves everywhere else form the peripheral nervous system. Nerve cells, called neurones, pass messages to each other across gaps called synapses, using chemicals called neurotransmitters.
The autonomic nervous system regulates glands and organs, including breathing, heartbeat and metabolism, without conscious effort. Its sympathetic branch prepares the body for activity and makes the heart beat faster and stronger. Its parasympathetic branch looks after the body at rest, stimulates digestion and helps you relax.
Connections
15 connections on the map. Select a topic to read its page.
Brain and nervous system includes
The bowel has its own nervous system, and the brain's automatic nerves speed up or slow digestion.
Source: InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the nervous system work?
Under stress your body releases hormones such as adrenaline, and the sympathetic nervous system makes the heart beat faster and stronger.
Sources: healthdirect Australia, Stress; InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the nervous system work?
Serotonin is one of the brain's chemical messengers, called neurotransmitters.
Sources: healthdirect Australia, Antidepressants; Better Health Channel (Victorian Government), Nervous system
Dopamine is a chemical in your brain that is vital for the control of your muscles and movement.
Brain and nervous system is affected by
Too much vitamin B6 from supplements can cause peripheral neuropathy, the TGA warns.
Sources: Therapeutic Goods Administration, Medicines containing vitamin B6 (pyridoxine, pyridoxal or pyridoxamine); NIH Office of Dietary Supplements, Vitamin B6 fact sheet for consumers
A stroke happens when the blood supply to part of the brain is suddenly reduced.
Source: healthdirect Australia, Stroke
Dementia is a group of conditions that gradually affect brain function.
Source: healthdirect Australia, Dementia
Parkinson's disease mainly affects movement and mood, and gets worse over time.
Brain and nervous system needs
DHA levels are especially high in the brain and retina.
Sources: NIH Office of Dietary Supplements, Omega-3 fatty acids fact sheet for consumers; NIH Office of Dietary Supplements, Omega-3 fatty acids: fact sheet for health professionals
Vitamin B12 helps keep nerve cells healthy, and a shortage can cause numb or tingling hands and feet.
Source: NIH Office of Dietary Supplements, Vitamin B12 fact sheet for consumers
Potassium helps your nerves, muscles and heart to work.
Brain and nervous system helps control
The sympathetic nervous system makes the heart beat faster and stronger.
Source: InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the nervous system work?
The bowel has its own nervous system. The parasympathetic system stimulates digestion and the sympathetic system slows it.
Source: InformedHealth.org (IQWiG), NCBI Bookshelf, In brief: How does the nervous system work?
Brain and nervous system is linked with
The hypothalamus and the pituitary gland work together to regulate body functions, and the hypothalamus releases hormones that help control the pituitary.
Source: healthdirect Australia, Endocrine glands and their hormones
Brain and nervous system is controlled by
- Slow, relaxed breathing Supported
Deliberately copying a relaxed breathing pattern seems to calm the nervous system.
Source: Better Health Channel (Victorian Government), Breathing to reduce stress
Medicines and supplements
General education only. Never start, stop or change a medicine without your prescriber.
Sources
Each connection above names its own source. See every source AskBioMap uses.
Summarised from the Better Health Channel, InformedHealth.org and healthdirect. Sources read on 13 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.