Producing, Preventing, and Explaining Persistent Complex Subliminal Stimulation Effects

Strong recent focus on unconscious processes has increased interest in subliminal stimulation and similar experimental technologies. Assumptions about the persistence of effects of unconscious stimulation are generally conservative, referring to seconds or minutes (Silverman, 1977; Velmans, 1991). In Study I, five experiments (N = 365) showed complex effects of unconscious stimulation ten days after subliminal exposure, implying that persistence estimates need reevaluation. Experimental stimuli were "mommy and I are one" (MIO) and "mommy and I are dissimilar" (MIDIS), and neutral control stimuli. Effects consisted of higher correlations between measures pertaining to the self-mother relationship and measures of psychological adjustment. These ethically problematic findings prompted investigation in Study II of whether debriefing information to participants could prevent persistent effects of subliminal stimuli, an issue not previously investigated. Two experiments (N=188) tested two kinds of information to participants following subliminal MIDIS or control stimulation. Results showed different persistent effects depending on participant sex. Simple information about the stimulus was effective in preventing these, but elaborate information describing the effects and mechanisms for them was not. The findings have implications for ethical recommendations for subliminal research, and suggest that this unexplored area requires more attention. In Study III, a theoretical account for the persistent effects is presented, based on unconscious activation of a relational schema containing goal motivation. Unless the goal is fulfilled or activation dissipates due to attributability or irrelevance of the goal, the activation will be maintained (motivated maintenance). Being unconscious, the influence results in automatic schematic processing of environmental cues, including perceptual, judgment, and behavioral biases. These in turn interactively maintain the activation of the schema (interactive maintenance). The discussion includes the conclusion that previous estimates of the persistence of unconscious stimulation effects need revision. Theoretical and empirical questions concerning the studies are discussed and ethical research implications are considered