Eye tracking cognitive load using pupil diameter and microsaccades with fixed gaze

Abstract

Pupil diameter and microsaccades are captured by an eye tracker and compared for their suitability as indicators of cognitive load (as beset by task difficulty). Specifically, two metrics are tested in response to task difficulty: (1) the change in pupil diameter with respect to inter- or intra-trial baseline, and (2) the rate and magnitude of microsaccades. Participants performed easy and difficult mental arithmetic tasks while fixating a central target. Inter-trial change in pupil diameter and microsaccade magnitude appear to adequately discriminate task difficulty, and hence cognitive load, if the implied causality can be assumed. This paper’s contribution corroborates previous work concerning microsaccade magnitude and extends this work by directly comparing microsaccade metrics to pupillometric measures. To our knowledge this is the first study to compare the reliability and sensitivity of task-evoked pupillary and microsaccadic measures of cognitive load.

What Eye Movements Reveal About Later Comprehension of Long Connected Texts

“…In addition, the current work focused on high-level, global features as they are more generalizable, are robust to tracking errors, and matched the level of resolution (page and text level) of comprehension assessments. However, future studies may consider whether including locally mapped features improves prediction accuracy, alongside other more fine-grained features not used in the present study, such as pupil diameter and microsaccades, which are known to reflect processes relevant to reading comprehension such as cognitive load (Krejtz, Duchowski, Niedzielska, Biele, & Krejtz, 2018). It is also worth noting that the present study used eye trackers with relatively low sampling rates of 60-120 Hz, which renders measurement of saccade length somewhat imprecise, so replication with more advanced eye tracking is warranted.…”

The effects of interior design on wellness – Eye tracking analysis in determining emotional experience of architectural space. A survey on a group of volunteers from the Lublin Region, Eastern Poland

“…Changes in pupil size can also be a measure of stress experienced in reaction to presented visual materials [38]. It should be remembered, however, that this relationship is complex, since the pupil size can be also related to the load of cognitive processing [26,39,40,41], the quantity of light 1 or the colour in the sight stimuli and luminance-contrast [42,43].…”

Pupil diameter differentiates expertise in dental radiography visual search

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