Question: How does your brain send electrical signals so fast?

Emily Mattacola answered on 11 Nov 2019:

The human brain is absolutely amazing! You have roughly 100 billion nerve calls in your brain, which are special cells called neurons. Each neuron is connected with thousands of others, but each connection is really specific – your brain is really good at knowing which neuron needs to talk to the next neuron to send a message, even when there are so many of them in your brain, and they’re so interconnected. That means that the message can be sent much quicker than if your brain was sending out messages to lots of neurons that don’t need or can’t process the information, so it’s these specific connections that help to mean the message gets through quickly.

The connections between neurons are called synapses. When a message reaches a synapse, it triggers the release of a chemical called a neurotransmitter, from the end of one neuron (the end part of the neuron is called the nerve terminal). The neurotransmitter jumps across the gap between the two neurons, and is received by the next neuron. The bit of the neuron which receives the message is called the dendrite. The dendrite recognises the neurotransmitter, which causes electrical changes in the neuron, which trigger it to release the neurotransmitter to the next neuron, and so on. It’s an incredibly complex, but very efficient system.