Until recently, it was commonly believed by intelligence experts that people reach the height of their intellectual peak by the time they’re twenty. 2Lately, however, scientists have discovered that our minds continue to grow long after we are fully developed physically. 3In addition, some psychologists are expanding their notion of what makes up intelligence. 4Dr. Robert Sternberg of Yale University, for example, outlines seven different areas of intelligence, including musical ability and self-knowledge.