Investigated the mental control of mood and mood-related thought. In Exp 1, Ss reminiscing about a happy or sad event were asked to make their mood positive, were given no instructions, or were asked to make their mood negative. Ss attempting mood control without an imposed cognitive load were successful, whereas those who attempted control while rehearsing a 9-digit number not only failed to control their moods, but also showed self-reported mood change opposite the mood they intended to create. In Exp 2, Ss attempting to control mood-related thoughts under cognitive load showed increased accessibility of those thoughts contrary to the direction of intended control in a Stroop-type color-naming task.
Wegner, D. M., Erber, R., & Zanakos, S. (1993). Ironic processes in the mental control of mood and mood-related thought. Journal of Personality and Social Psychology, 65(6), 1093-1104.
http://dx.doi.org/10.1037/0022-3514.65.6.1093