Pupillary Correlates of Fluctuations in Sustained Attention

Abstract

The current study examined pupillary correlates of fluctuations and lapses of sustained attention. Participants performed a sustained attention task with either a varied ISI or a fixed ISI (fixed at 2 or 8 sec) while pupil responses were continuously recorded. The results indicated that performance was worse when the ISI was varied or fixed at 8 sec compared with when the ISI was fixed at 2 sec, suggesting that varied or long ISI conditions require greater intrinsic alertness compared with constant short ISIs. In terms of pupillary responses, the results demonstrated that slow responses (indicative of lapses) were associated with greater variability in tonic pupil diameter, smaller dilation responses during the ISI, and subsequently smaller dilation responses to stimulus onset. These results suggest that lapses of attention are associated with lower intrinsic alertness, resulting in a lowered intensity of attention to task-relevant stimuli. Following a lapse of attention, performance, tonic pupil diameter, and phasic pupillary responses, all increased, suggesting that attention was reoriented to the task. These results are consistent with the notion that pupillary responses track fluctuations in sustained attention.

Pupillometry tracks fluctuations in working memory performance

“…Additionally, in prior work, pretrial pupil diameter does not always show a consistent pattern preceding lapses of attention. In some prior studies, pretrial pupil is significantly smaller preceding reports of mind-wandering and mindblanking, suggesting people were in a low-arousal state in these instances (Unsworth & Robison, 2016a;Unsworth et al, 2018). In other studies, pretrial pupil diameter is significantly larger preceding reports of mind-wandering (Franklin et al, 2013;Pelagatti et al, 2018).…”

“…In a separate yet related line of research, we have been investigating the pupillary correlates of attentional lapses within sustained attention tasks (Unsworth & Robison, 2016a, 2018aUnsworth et al 2018). In these studies, we have observed differences in both pretrial pupillary dynamics and task-evoked pupil dilations when participants are in relatively disengaged attentional states.…”

“…Specifically, when people report being in an off-task attentional state (e.g., mind-wandering or "zoning out"), task-evoked pupil dilations were shallower and performance on the task was worse (i.e., reaction times were longer). Further, long reaction times were preceded by reductions in pupil dilation in preparation for the upcoming stimulus (Unsworth et al, 2018). Theoretically, pretrial pupil diameter provides an index of baseline activity in the locus coeruleusnorepinephrine (LC-NE) neuromodulatory system, which is partially responsible for regulating the allocation of attentional resources, maintaining alertness, and attending to task-relevant sources of information in the environment (Aston-Jones & Cohen, 2005;Gilzenrat et al, 2010;Murphy et al, 2011;Sara, 2009).…”

Motivation alters implicit temporal attention through sustained and transient mechanisms: A behavioral and pupillometric study

“…With regard to temporal preparation, several studies have found increased pupil diameter prior to target onset in fixed foreperiod tasks with predictable target timing (Akdoǧan & van Rijn, 2016;Unsworth et al, 2018;Van der Molen, Boomsma, Jennings, & Nieuwboer, 1989). In contrast, prestimulus pupil increase in variable foreperiod paradigms is either smaller compared to fixed foreperiod tasks (Jennings, Molen, & Steinhauer, 1998) or unreported (Unsworth et al, 2018). It may therefore be possible that prestimulus pupil diameter mostly reflects explicit temporal preparation (predictable timing) and not implicit temporal preparation.…”

“…In particular, prestimulus pupil diameter in anticipation of a target has been associated with proactive, preparatory attention, whereas phasic poststimulus pupil responses may reflect reactive attention (Chatham, Frank, & Munakata, 2009;Chiew & Braver, 2013). Prestimulus pupil diameter is found to increase prior to stimulus onset in predictable timing paradigms (Akdoǧan & van Rijn, 2016;Unsworth, Robison, & Miller, 2018), reflecting attentional readiness. Moreover, reward manipulations have been shown to increase prestimulus pupil size (Chiew & Braver, 2013), possibly reflecting increased proactive attention.…”