She said they were currently funding research into drugs that mimic the action of nerve growth factor (NGF), the name given to the gene therapy involving stimulating cell function.

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Synapses are the junctions between nerve cells, and their action is central to learning and memory.

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Their main finding was that a nerve impulse, now known as an action potential, is caused by the movement in opposite directions across the axon's surface membrane of sodium and potassium ions.

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The stimulation came in two forms: pulses of electricity and pulses of chemicals that mimic the action of serotonin and dopamine, two molecules that transmit messages between nerve cells.

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It sits inside the surface of a cell and springs into action when signaled by other cells, activating proteins that temporarily boost the connection between two nerve cells.

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