The Appetitive Motivation Scale (AMS) measures how strongly a person responds to reward. It was written to capture the Behavioural Approach System in Gray’s Reinforcement Sensitivity Theory as reward-reactivity, and to keep that separate from impulsivity.
Luke Smillie and I introduced the scale in 2004 and tested it against other approach measures in 2005. In 2008 Andrew Cooper led a psychometric revision. In a sample of 1,366 students, factor analysis and item response theory identified several weak items, which were removed. The revised scale measures a single dimension more cleanly. In a second sample it related more strongly to a reward-reactivity factor than to an impulsivity factor, compared with other approach scales.
Key references
- Jackson, C. J., & Smillie, L. D. (2004). Appetitive motivation predicts the majority of personality and an ability measure: A comparison of BAS measures and a re-evaluation of the importance of RST. Personality and Individual Differences, 36, 1627–1636. doi:10.1016/j.paid.2003.06.010
- Smillie, L. D., & Jackson, C. J. (2005). The appetitive motivation scale and other BAS measures in the prediction of approach and active avoidance. Personality and Individual Differences, 38, 981–994. doi:10.1016/j.paid.2004.09.013
- Cooper, A. J., Smillie, L. D., & Jackson, C. J. (2008). A trait conceptualization of reward-reactivity: Psychometric properties of the Appetitive Motivation Scale (AMS). Journal of Individual Differences, 29(3), 168–180. doi:10.1027/1614-0001.29.3.168
- Smillie, L. D., Jackson, C. J., & Dalgleish, L. I. (2006). Conceptual distinctions among Carver and White's (1994) BAS scales: A reward-reactivity versus trait impulsivity perspective. Personality and Individual Differences, 40, 1039–1050. doi:10.1016/j.paid.2005.10.012