Abstract

Cognitive involvement in reading causes variations in the tonus of autonomic nerve system. The aim of this study was to examine the effect of short-term cognitive load on accommodation and pupils' absolute values and temporal variability in test persons performing three different types of tasks. We aimed to show how cognitive tasks of different type and difficulty level affect accommodation and pupil behavior during a short time interval. Participants (n=58; mean age 16.4 years, SD=0.56) performed reading from a 10-inch LCD screen placed at 40cm distance. Three different types of tasks (numerical, textual, and the Stroop task), each at three different levels of cognitive load were introduced. Participants had 90s to complete each task. Accommodative and pupillary responses were measured with videoretinoscope Power Refractor 3 at 50Hz. Pupil size was largest in the Stroop task (M=5.20mm, SD=0.75mm), followed by the numerical tasks (M=5.02mm, SD=0.72mm) and textual tasks (M=4.78mm, SD=0.71mm). Accommodative fluctuations - measured as accommodation SD - were largest in the textual tasks (M=0.67 D, SD=0.34 D), followed by the numerical tasks (M=0.61 D, SD=0.40 D) and the Stroop task (M=0.52 D, SD=0.21 D). In our experiment, short-term cognitive load was associated with altered pupillary and accommodative response to near tasks. In conflicting tasks (Stroop) or in performing continuing calculations, the pupils were larger; in tasks requiring logical reasoning, the accommodative fluctuations were greater. These effects can potentially be associated with current near-point stress and myopia growth models.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.