Task sets serve as boundaries for the list-wide proportion congruency effect.

= 144) to investigate the boundaries of a laboratory index of these control processes called the list-wide proportion congruency effect (LWPCE). Specifically, we investigated whether (a) sensory modalities on their own or (b) task sets based on sensory modalities serve as boundaries for the LWPCE. Experiments 1 and 2 revealed that the control processes underlying the LWPCE transfer from trials with auditory distractors to trials with visual distractors only when the task structure biases participants to think of auditory and visual stimuli as belonging to the same task. Experiment 3 revealed that participants exhibit such a bias when they cannot classify most of the trials as "purely visual" or "purely auditory." These findings support the view that task sets serve as boundaries for the LWPCE. They also reveal the precise conditions under which control processes transfer across different sensory modalities. (PsycInfo Database Record (c) 2026 APA, all rights reserved).