It takes sound waves in the environment and transforms them into nerve impulses to the auditory nerve.

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These other two types have supporting, rather than starring roles in the brain, and cannot transmit nerve impulses.

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Caffeine works by suppressing the neurotransmitters in your brain that would normally release nerve impulses that make you tired.

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Listening to 100 neurons firing is like listening to static, but a computer can pick up different patterns in the nerve impulses as a person thinks about moving in different ways.

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It is the movement of potassium (and also sodium) ions that causes the electrical impulses that nerve cells carry including the impulses found in slow-wave sleep.

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Just as importantly, the resulting nerve cells were able to conduct electrical impulses and could form the specialised junctions called synapses, by means of which nerve cells talk to each other.

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