Abstract
Meta‐analysis that assessed the magnitude of behavior change produced by subliminal vs. supraliminal drive‐related stimuli was performed on all subliminal psychodynamic activation (SPA) studies that employed both types of stimuli (N of studies = 11, N of subliminal‐supraliminal comparisons = 43). The analysis revealed that subliminal presentation of drive‐related stimuli produced significantly stronger effects on behavior than supraliminal presentation of the same stimuli. Stimulus content, type of outcome measure, and subject characteristics all influenced the magnitude of subliminal‐supraliminal response differences. These results support Silverman's (1983) hypothesis that drive‐related stimuli must be presented subliminally in order to produce SPA effects. Furthermore, given the pattern of subliminal‐supraliminal effect sizes obtained, a partial cue hypothesis of SPA effects is not tenable. Implications of these findings for research that examines the restricting effects of awareness on responding to drive‐ and affect‐related stimuli are discussed.