Exploring age-related changes in saccades during cognitive tasks in healthy adults

Hee Won Yang; Jin Yeong Choe; Soo Rim Noh; Jeong Lan Kim; Ji Won Han; Ki Woong Kim

doi:10.3389/fnbeh.2023.1301318

Exploring age-related changes in saccades during cognitive tasks in healthy adults

Front Behav Neurosci. 2024 Jan 5:17:1301318. doi: 10.3389/fnbeh.2023.1301318. eCollection 2023.

Authors

Hee Won Yang¹, Jin Yeong Choe², Soo Rim Noh³, Jeong Lan Kim⁴, Ji Won Han^{5

6}, Ki Woong Kim^{2

5

6}

Affiliations

¹ Department of Psychiatry, Chungnam National University Hospital, Daejeon, Republic of Korea.
² Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Republic of Korea.
³ Department of Psychology, Chungnam National University, Daejeon, Republic of Korea.
⁴ Department of Psychiatry, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
⁵ Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
⁶ Department of Psychiatry, Seoul National University, College of Medicine, Seoul, Republic of Korea.

Abstract

Introduction: Although eye movements such as saccades are related to internal cognitive processes and are independent of visual processing, few studies have investigated whether non-visual cognitive tasks simultaneously affect horizontal and vertical saccades in younger and older adults.

Methods: We recruited 28 younger adults aged 20-29 years and 26 older adults aged >60 years through advertisements in community settings. All participants were free of major psychiatric, neurological, or ocular diseases. All participants performed the mental arithmetic task (MAT) and verbal fluency task (VFT). The primary measures were saccade parameters, including frequency, mean amplitude, and mean velocity.

Results: During MAT and VFT, the frequencies of horizontal and vertical saccades increased (p = 0.0005 for horizontal saccade in MAT; p < 0.0001 for horizontal saccade in VFT; p = 0.012 for vertical saccade in MAT; p = 0.001 for vertical saccade in VFT), but were comparable between MAT and VFT. The old group showed a slower vertical saccade than the young group during the tasks (p = 0.011 in the MAT phase; p = 0.006 in the VFT phase). The amplitude of the horizontal saccade decreased in both groups during MAT compared to the resting period (p = 0.013), but did not change significantly during VFT.

Discussion: Saccade parameters can change during non-visual cognitive tasks with differences between age groups and saccade directions. This study significantly contributes to our understanding of the distinct dynamics of horizontal and vertical saccades across various age group in cognitive aging, despite its restricted focus on specific saccade parameters and cognitive tasks, and inclusion solely of cognitively normal individuals. This study highlights the importance of saccade analysis in elucidating age-related cognitive changes. In conclusion, saccades should be examined in future studies as a potential non-invasive biomarker for early detection of cognitive decline and neurodegenerative diseases.

Keywords: arithmetic; memory; non-visual task; older adults; saccade.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the National Research Foundation of Korea (NRF) funded by the Korea Government (MSIT) [grant number 2015R1D1A1A01059676]. The funder had no role in the conception, the collection of data or analysis, or in preparation of the manuscript.