Arvid Carlsson, 1923–, Swedish pharmacologist, grad. Univ. of Lund, Sweden, (M.D., Ph.D., 1951). Carlsson was a professor at the Univ. of Lund (1951–59) and at the Univ. of Gothenburg, Sweden (1959–89). In 2000 he, Paul Greengard, and Eric Kandel were awarded the Nobel Prize in physiology or medicine for their discoveries concerning signal transduction in the nervous system. The nerve cells in the human brain are linked by a complex network of nerve processes, with messages being transmitted via various chemical transmitters. Carlsson was cited for discovering that dopamine is one of those transmitters and that it is critical to movement control. His research led to the realization that lack of dopamine in certain parts of the brain causes Parkinson's disease. See also neurotransmitter.