Tracking Behavioral and Physiological Dynamics in Perceptual Decisions during Sustained Attention

We continuously rely on our ability to make decisions about incoming sensory stimuli. However, these decisions are highly variable, showing differences in accuracy and response time even when based on identical information. Although this variability is often attributed to random noise, recent work suggests it may reflect systematic processes, such as fluctuations in engagement states. Pupil diameter has been implicated as an indicator of these fluctuations. Previous research has reported both linear and quadratic relationships between baseline pupil diameter and behavioral engagement, depending on task structure and analytical steps. The present study used a threefold approach to reproduce, replicate, and extend these findings by examining perceptual decision-making and its psychophysiological correlates during sustained attention in a trial-based task without breaks. Seventy-two participants (N = 72) completed a 32-minute self-paced perceptual decision-making task in which they...Show moreWe continuously rely on our ability to make decisions about incoming sensory stimuli. However, these decisions are highly variable, showing differences in accuracy and response time even when based on identical information. Although this variability is often attributed to random noise, recent work suggests it may reflect systematic processes, such as fluctuations in engagement states. Pupil diameter has been implicated as an indicator of these fluctuations. Previous research has reported both linear and quadratic relationships between baseline pupil diameter and behavioral engagement, depending on task structure and analytical steps. The present study used a threefold approach to reproduce, replicate, and extend these findings by examining perceptual decision-making and its psychophysiological correlates during sustained attention in a trial-based task without breaks. Seventy-two participants (N = 72) completed a 32-minute self-paced perceptual decision-making task in which they indicated which of two displayed stimuli had higher contrast. Participants were assigned to either a full-instructions condition (n = 35) or a minimal-instructions condition (n = 37). Behavioral and pupillary measures were analyzed as a function of time-on-task using linear and quadratic models. Across all participants, performance improved over time while pupil diameter decreased. No relationship between pupil diameter and performance was observed in the full-instructions condition. In contrast, the minimal-instructions condition showed a reliable inverted-U relationship between pupil diameter and response time metrics, which remained significant after accounting for time-on-task and across time scales (p ≤ .001). These findings do not support a consistent linear relationship between arousal and performance. Instead, they indicate that performance might be optimized at intermediate levels of arousal and that this relationship is not uniform. This suggests that arousal–performance dynamics in perceptual decision-making could be context-dependent and may differ with increased task demands.Show less

Leiden University Student Repository

Documents

In Collections

Tracking Behavioral and Physiological Dynamics in Perceptual Decisions during Sustained Attention