1. with regard to trial and error studies, a trend where one occurrence varies with a different occurrence- with regard to operant conditioning studies, a supported trial (S) might vary with a non-supported trial (N), producing an SNSNSN trend as a result. 2. the trend of performance created by this itinerary which is more potent reaction toward S than toward N trials.
ALTERNATION: “The alternation of exposure to different stimuli ended up showing a marked increase in stress placed upon the independent variable.”