Verbal Behavior

SΔp: The missing discriminative stimulus for nonpunishment.

“…O’Donnell defined the S Dp as, “a stimulus condition in the presence of which a response has a lower probability of occurrence than it does in its absence as a result of response-contingent punisher delivery in the presence of the stimulus” (p. 262). This is consistent with how others have defined the discriminative stimulus for punishment (e.g., Fisher et al, 2011; Malott & Shane, 2014; Michael, 2004; Miltenberger, 2016). However, unlike others, O’Donnell stated that to prevent confounding the effects of punishment and extinction, the experimental procedures that would establish an S Dp are (a) a punishment contingency and (b) an ongoing reinforcement contingency for the same response.…”

“…It is with this goal in mind that we revisit the definition of the S Dp . The discriminative stimulus for punishment had been discussed long before O’Donnell (2001) proposed the term and symbol, S Dp (e.g., Chance, 1999; Malott et al, 2000; Michael, 1980; Miller, 1997; Sulzer-Azaroff & Mayer, 1991); however, at the time, people were using different symbols and there was no consensus as to what to call a stimulus correlated with punishment contingencies. The S Dp filled an important need, as precise and consistent terminology facilitates scientific communication within a discipline.…”