These vector images are based on original versions of the Self-Assessment-Manikin scales developed by Lang (1980).
ref.
Lang, P. J. (1980). Behavioral treatment and bio-behavioral assessment: computer applications. In J. B. Sidowski, J. H. Johnson, & T. A. Williams (Eds.), Technology in mental health care delivery systems (pp. 119-l37). Norwood, NJ: Ablex.