Researchers identified some 3,300 types of brain cells, an order of magnitude more than was previously known, and have only a dim notion of what most of them do.Researchers identified some 3,300 types of brain cells, an order of magnitude more than was previously known, and have only a dim notion of what most of them do.Read MoreResearch, Brain, Genetics and Heredity, your-feed-science, Allen Institute for Brain Science, Lein, EdNYT > Health