Seeing the Forrest through the trees: Oculomotor metrics are linked to heart rate

PLoS One. 2022 Aug 2;17(8):e0272349. doi: 10.1371/journal.pone.0272349. eCollection 2022.

Abstract

Fluctuations in a person's arousal accompany mental states such as drowsiness, mental effort, or motivation, and have a profound effect on task performance. Here, we investigated the link between two central instances affected by arousal levels, heart rate and eye movements. In contrast to heart rate, eye movements can be inferred remotely and unobtrusively, and there is evidence that oculomotor metrics (i.e., fixations and saccades) are indicators for aspects of arousal going hand in hand with changes in mental effort, motivation, or task type. Gaze data and heart rate of 14 participants during film viewing were used in Random Forest models, the results of which show that blink rate and duration, and the movement aspect of oculomotor metrics (i.e., velocities and amplitudes) link to heart rate-more so than the amount or duration of fixations and saccades. We discuss that eye movements are not only linked to heart rate, but they may both be similarly influenced by the common underlying arousal system. These findings provide new pathways for the remote measurement of arousal, and its link to psychophysiological features.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blinking
  • Eye Movements*
  • Heart Rate
  • Humans
  • Saccades*
  • Task Performance and Analysis

Grants and funding

This work was supported by ERC [ERC-CoG-863732], https://erc.europa.eu/, awarded to SVdS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.