What is a synapse?

When a nerve impulse reaches the synapse at the end of a neuron, it cannot pass directly to the next one. Instead, it triggers the neuron to release a chemical neurotransmitter. The neurotransmitter drifts across the gap between the two neurons. On reaching the other side, it fits into a tailor-made receptor on the surface of the target neuron, like a key in a lock. This docking process converts the chemical signal back into an electrical nerve impulse.

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Neurotransmitters bridge the gap (synapse) between one neuron and the next.

Why use neurotransmitters?

Your brain uses over 50 different neurotransmitter chemicals. Although electrical signalling between neurons is quicker and more energy efficient, chemical signalling is far more versatile. The signals carried by some neurotransmitters excite the target cell while others dampen down their activity, depending on the type of neurotransmitter released at the synapse and the receptors they reach. This is what sharpens the contrast between light and dark in the eye, for example.

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Neurotransmitters both carry and modify signals in the nervous system.


Principal Funder:

Wellcome trust

Major Sponsors:

GlaxoSmithKline life technologies