References: Charles, S. T., Reynolds, C. A. & Gatz, M. (2001). Age-Related Differences and Change in Positive and Negative Affect Over 23 Years. Journal of Personality and Social Psychology, 80(1). For more details see: http://www.apa.org/research/action/emotional.aspx American Psychological Association, November 28, 2005

Written by Susan Turk Charles Reynolds, C. A. and Gatz, M. (2001) written by the American Psychological Association, adapted by Juanita N. Baker, Ph.D.