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The 2000 Nobel Prize in Physiology or Medicine was awarded jointly to the neuroscientist, Eric Kandel as well as Arvid Carlsson and Paul Greengard for their discoveries concerning "signal transduction in the nervous system." Their research helped elucidate the fundamental mechanisms by which signals are transmitted between nerve cells in the brain, leading to a deeper understanding of brain function and disorders like Parkinson's and Alzheimer's diseases.