Three scientists who have made important contributions to understanding the memory and mood aspects of the brain were awarded the Nobel Prize in medicine yesterday. The winners are Dr. Arvid Carlsson, 77, of Sweden and two New Yorkers, Dr. Eric R. Kandel, 70, of Columbia University and Dr. Paul Greengard, 74, of Rockefeller University. The three will share the prize money of nearly $915,000. Among the contributions that these men have made include advancements in the study of Parkinson’s disease. When Greengard got the call with the good news from the Nobel committee in Stockholm, it was just after five in the morning in the U.S. “I said to my wife, ‘Who’s the jerk that’s calling me?’ ” he told New York’s Daily News.