Trends in Research Related to Pupillometry From 1999 to 2025: A Bibliometric and Visualized Analysis

Objective: Pupillometry is a noninvasive method which measures changes in the size of the pupil intending to study cognitive processes and identify networks that are related to specific attentional states such as attention, mental effort, working memory, and many others, through monitoring pupil size. This study aimed to investigate hotspots and global research trends in the field of pupillometry by bibliometric analysis.Methods: Publications from 1999 to 2025 in the Web of Science database were extracted and analyzed using bibliometric methods. This study utilized the R Bibliometrix package, along with the web platforms VOS Viewer and CiteSpace.Results: A total of 2,897 peer-reviewed documents were obtained, and the annual research output from 1999 to 2025 has increased significantly. The role of pupillometry in this research has been investigated by over 11,534 authors coming from 3,019 institutions in 89 countries or regions. According to the report, the United States had the highest number of publications, while Psychophysiology was the most productive journal. Amongst the most active academic institutions, the University of Toronto stood out as the most active, and among the most prolific authors, Olson Daiwai emerged as the most prolific. We found that keywords from pupillometry related including locus-coeruleus (304 occurrences), attention (240 occurrences), pupil (239 occurrences), pupillary light reflex (237 occurrences), and retinal ganglion cells (135 occurrences) had high frequency and among the strongest citation burst keywords, “infrared pupillometer”, “in situ keratomileusis”, “retinal ganglion cells”, and “refractive surgery” showed citation bursts from 1999 to 2025, corresponding with the increase in published documents.Conclusions: It can be noted that this study was the first comprehensive bibliometric study to summarize trends and developments in pupillometry research from a bibliometric perspective. By analyzing bibliometric data on development trends in pupillometry development trends, developers or researchers would be able to propose future research directions as well as pursue further collaborations.