Question: what 's the most powerful signal whch can be sent to your brain (through your body)?

Eleanor Parker answered on 10 Mar 2014:

Interesting question. Well, all signals to the brain are carried by cells called neurons. The signals are a mix of electrical and chemical signals. The electrical signal travels along the neuron then when it reaches the end it turns into a chemical signal to cross the gap to the next neuron. I don’t think any signals are more powerful than others, but some are faster. For example pain reflexes are vey fast. This is because the signal doesn’t travel all the way to your brain and back, just to your spinal cord.
But some people say that a smile is the most powerful signal to other peoples brains. Smile at someone and they are very likely to smile back 🙂