Question: how does the brain work your body

Victoria Cox answered on 6 Nov 2020:

Hi there. I will let one of the neuroscientists we have in the zone answer this properly (I work on infectious diseases not brains) but here is my answer below.

The brain and spine are part of your nervous system which connect to all your nerve cells. The nervous system allows you to respond to things in your environment. For example, if you touch something too hot this happens: you have sensors in your skin which activate a nerve cell and this causes a signal to be sent to the brain, the brain receives this signal and then sends another signal to the muscles in your hand to move them away from the hot thing. The signals are sent along the nerve cells.

As well as nerves, the brain also signals to the body using hormones. Hormones are proteins that the body makes that travel in the blood. For example when you are stressed or in danger, your brain activates the ‘fight or flight’ response and causes your adrenal glands (which are above your kidneys) to produce the hormone adrenaline. This hormone travels in the blood and causes a lot of changes such as increased breathing and faster heart rate. These changes mean that more oxygen can be breathed in and delivered to your muscles, so more respiration can happen in the muscles. Respiration uses oxygen and glucose (sugar from your food) to release energy. The brain causes your body to do this so you will have more energy if you need to run away or fight.