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The faster a person is diagnosed after a stroke, the sooner they can be treated and the more cognitive function can be preserved. But it takes time to identify the problem from a brain scan — an average of 87 minutes after the images have been captured, for cases flagged as urgent, according to one study1. In that time, tissue dies. Researchers have found that someone experiencing a stroke that cuts off flow through a large blood vessel will typically lose 120 million neurons, 830 billion synapse connections and 714 kilometres of nerve fibre in 1 hour — the equivalent of ageing by about 3.5 years2.