Real-time feedback amplifies the interactive effect between conflict expectation and stimulus incongruency on a speech-to-text Stroop application

Feedback is crucial for keeping people engaged in cognitively demanding behavioral tasks. Previous research has demonstrated real-time feedback could enhance behavioral performance in tasks involving working memory. However, the effects of real-time feedback on cognitive control functions, such as conflict monitoring, and its influence across different age groups remain unclear. To address these questions, we developed a web-based speech-Stroop application that provided real-time feedback to users from three age groups: young adults (18-40 years), middle-aged adults (41-60 years), and older adults (61-80 years). The study aimed to investigate how feedback affected conflict expectation and stimulus incongruency in the speech-Stroop task, while manipulating the ratio of congruent and incongruent trials in different blocks. Overall, older adults exhibited slower and less accurate responses compared to the younger groups, indicating a decline in executive function with aging. Additionally, older adults experienced greater cognitive interference from incongruent stimuli. Importantly, real-time feedback resulted in longer response times, suggesting that the feedback made participants more cautious. However, no significant interactions were observed between feedback, task factors, or age groups. Furthermore, feedback did not affect overall accuracy levels. Nevertheless, real-time feedback amplified the interactive effects between conflict expectation and stimulus incongruency on accuracy. In trials without feedback, comparable degrees of cognitive interference were observed across different block types with varying ratios between congruent and incongruent stimuli. Conversely, trials with real-time feedback exhibited significantly increased cognitive interference in blocks where incongruent stimuli were rare and unexpected. Notably, these feedback effects on the interaction between conflict expectation and stimulus incongruency were consistent across all age groups. Together, our study provides valuable insights into the influence of real-time feedback on cognitive control processes. The findings can guide the development of user-friendly and engaging cognitive monitoring and training applications suitable for all age groups.