How does the human brain send messages to other parts of the body?
Mariko Yanagisawa from Stockton on Tees (Aged 5-14)
Filed under: age 5-14, Answered Big Questions, Biology Big Questions, Brain Big Questions, David Small's Big Answers, Nicola Corbett's Big Answers, Steve Busby's Big Answers
Two ways
1. it sends signals along the nerves
2. it releases chenicals that act as signals in different parts of the body
The human brain sends messages to other parts of the body through a network of connecting wires (neurons) called the nervous system. The brain sends these messages in the form of an electrical current (action potentials), these currents then travel through the wires to the part of the body the brain wants to talk to, and then that part of the body will perform an action.
Example:
If you touch something hot a very fast message is sent from the hand to the brain through the nervous system, the brain then works out what the problem is and sends a message back to the hand telling it to move away.
The brain sends an electical signal to parts of the body through nerves. For example, if you want to move your arm the part of the brain involved in movement, the motor cortex (roughly the top of your brain), sends an electrical signal along the nerves through the brain stem (the very bottom of the brain), part way down the spinal chord (which is inside your spine) and then into the arm to the muscles which are required to contract or relax to allow the arm to move. If it were your leg then the electrical signal would go all the way down your spinal chord.
(I’m a PhD neuroscience student.)