Same task rules, different responses: Goal neglect, stimulus-response mappings and response modalities

To complete complex tasks, individuals must actively maintain task rules to direct behavior correctly. Failure to use task rules appropriately, termed goal neglect, has been shown across both vocal and manual response modalities. However, previous goal maintenance studies have differed not only in the response modality that they require, but also in the complexity of the stimulus-response mappings that participants must use during the task. The present study examines the effects of both response modality and stimulus-response mapping complexity, separately, on the rate of goal neglect in a modification of a classic goal maintenance task. Seventy-two younger adults were administered a shape-monitoring task, with three between-subjects response conditions: a vocal response with a simple stimulus-response mapping, a vocal response with a complex stimulus-response mapping, and a manual response with a complex stimulus-response mapping. Contrasting the rate at which task rules were neglected between response conditions showed that participants using complex stimulus-response mappings committed more frequent goal neglect than those using simple mappings, but that participants using vocal or manual responses did not differ in their rate of goal neglect once both responses required complex mappings. This suggests that the need to represent novel and complex stimulus-response mappings, of any modality, at the same time as novel task rules within working memory leads to some task rules being insufficiently maintained.