The Role of Serotonin in Nonnormative Risky Choice: The Effects of Tryptophan Supplements on the "Reflection Effect" in Healthy Adult Volunteers. - Susannah E. Murphy; Carlo Longhitano; Rachael E. Ayres; Philip J. Cowen; Catherine J. Harmer; Robert D. Rogers (J. Cogn. Neurosci., 2009)