The Impact of Instructions on Individual Prioritization Strategies in a Dual-Task Paradigm for Listening Effort

Introduction Understanding how listeners execute a dual-task paradigm for listening effort would provide a benchmark for future studies and clinical implementations. Therefore, this study aimed to examine the impact of instructions on the prioritization strategy employed by individuals during a dual-task paradigm for listening effort by assessing dual-task interference. Methods The dual-task paradigm consisted of a primary speech understanding task in different listening conditions and a secondary visual memory task, both performed separately (baseline) and simultaneously (dual-task). Twenty-three normal-hearing participants (mean age: 36.8 years; 14 females) were directed to prioritize the primary speech understanding task in the dual-task condition, whereas another twenty-three (matched for age, gender, and education level) received no specific instructions regarding task priority. Both groups performed the dual-task paradigm twice (mean interval: 14.8 days). Dual-task interference was assessed by plotting the dual-task effect of the primary and secondary task against each other. Participants were classified based on their patterns of interference. Results The prioritizing group had more participants who achieved stable or better scores on the primary task in the dual-task condition compared to baseline. However, there was considerable variability in the prioritizing strategy employed at the individual level across listening conditions and test moments, regardless the given prioritization instructions. Conclusion Providing prioritization instructions was insufficient to ensure that an individual will mainly focus on the primary task and will stick to this strategy across listening conditions and test moments. These results raised certain reservations about the current usage of dual-task paradigms for listening effort.