Variability across time in implicit weight-related bias: Random noise or meaningful fluctuations?

Social psychologists have struggled with the vexing problem of variability over time in implicit bias. While many treat such variability as unexplainable error, we posit that some temporal variability, whether within persons or across society at large, reflects meaningful and predictable fluctuation based on shifts in the social-cultural context. We first examined fluctuations at the group-level in a Project Implicit data set of female participants who completed the Weight Implicit Association Test between 2004 and 2018 (N = 259,613). Extending our prior work showing that mass media celebrity fat-shaming increased women's implicit antifat bias, we show that celebrity body positivity events reduced such bias (Study 1a). We then focused on a specific form of body positivity-that is, celebrity "push-back" in response to fat-shaming. Whereas fat-shaming without antibias push-back was associated with spikes in negative weight attitudes, fat-shaming with push-back showed no change in such bias (Study 1b). Critically, however, closer analysis revealed that this apparent stability was due to the canceling out of opposing negative (fat-shaming) and subsequent positive (body positivity) influences-an effect that was obscured when the window of observation was expanded. Finally, in Study 2, we examined parallel effects at the individual level in a daily diary study. Consistent with the group-level, between-subjects data, women's intraindividual fluctuations in implicit attitudes were reliably predicted based on prior-day exposure to fat-shaming and/or body positivity influences. Taken together, our work highlights how both group- and individual-level variability across time can be meaningfully explained rather than treated as unexplainable or left as unexplained. (PsycInfo Database Record (c) 2023 APA, all rights reserved).