A bayesian investigation into inhibition mechanisms of contrast and assimilation

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The ability to inhibit distractors within an environment while focusing on specific information is crucial to proper functioning. In most inhibition tasks, such as Stroop, the to-be-ignored information affect the response to be more like the distractors rather than the target, termed assimilation. In other tasks, the opposite effect occurs, termed contrast. Contrast and assimilation are opposing effects that both occur when distracting information affects judgements. It is asked whether inhibition across contrastive and assimilative tasks have common underlying mechanisms or if they are distinct processes. A series of Bayesian hierarchical models were used to conduct a correlational analysis and assess the hypothesis. A task was designed, in which common target stimuli were used, that displayed large assimilation and contrast effects depending on the background context. Three models are discussed in detail to better understand the relationship between these two inhibition effects. A positive correlation was found between assimilation and contrast effects. Individuals who better inhibited assimilation-inducing contexts appear to be better able to inhibit contrast-inducing contexts. An overall summary of the analyses is provided.