{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T22:40:13Z","timestamp":1790808013174,"version":"4.1.0"},"reference-count":28,"publisher":"Association for Computing Machinery (ACM)","issue":"2","content-domain":{"domain":["dl.acm.org"],"crossmark-restriction":true},"short-container-title":["Proc. ACM Comput. Graph. Interact. Tech."],"published-print":{"date-parts":[[2026,6,1]]},"abstract":"<jats:p>A comprehensive signal-analytic examination is made of the detection of cognitive load from the measurement of pupil diameter oscillation. Earlier such computational methods failed to provide a real-time variant of frequency-based approaches and failed to justify various design choices. In this work, the problem is approached from first principles, considering what pupillary oscillations should be expected, both under rest and under (cognitive) load. Then three detection techniques are derived based on the Fast Fourier Transform (FFT), the Discrete Wavelet Transform (DWT), and the Butterworth filter to compute the Low\/High Frequency (LF\/HF) ratio. The work also covers the minimum signal duration required for each method, the theoretical range of the LF\/HF ratio, drawing from physiological and signal processing perspectives, and the minimum time window needed to produce output. It is shown that the Butterworth filter is better suited for real-time implementation than the other two.<\/jats:p>","DOI":"10.1145\/3803537","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T12:32:52Z","timestamp":1777638772000},"page":"1-20","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Real-Time Cognitive Load Measurement of Pupillary Oscillation"],"prefix":"10.1145","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1681-7878","authenticated-orcid":false,"given":"Andrew","family":"Duchowski","sequence":"first","affiliation":[{"name":"School of Computing","place":["Clemson, USA"]},{"name":"Clemson University","place":["Clemson, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"320","published-online":{"date-parts":[[2026,5,1]]},"reference":[{"key":"e_1_3_2_2_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.472746"},{"key":"e_1_3_2_3_1","doi-asserted-by":"publisher","DOI":"10.1145\/3204493.3204531"},{"key":"e_1_3_2_4_1","doi-asserted-by":"publisher","DOI":"10.1145\/3544549.3585650"},{"key":"e_1_3_2_5_1","doi-asserted-by":"publisher","DOI":"10.1145\/1117309.1117358"},{"key":"e_1_3_2_6_1","doi-asserted-by":"publisher","DOI":"10.1145\/2168556.2168582"},{"key":"e_1_3_2_7_1","first-page":"142","volume-title":"Handbook of Psychophysiology (2nd ed.)","author":"Beatty Jackson","year":"2000","unstructured":"Jackson Beatty and Brennis Lucero-Wagoner. 2000. The Pupillary System. In Handbook of Psychophysiology (2nd ed.), John\u00a0T. Cacioppo, Louis\u00a0G. Tassinary, and Gary\u00a0G. Bernston (Eds.). Cambridge University Press, Cambridge, MA, 142\u2013162."},{"key":"e_1_3_2_8_1","doi-asserted-by":"publisher","DOI":"10.21236\/ADA417743"},{"key":"e_1_3_2_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/0042-6989(71)90016-2"},{"key":"e_1_3_2_10_1","doi-asserted-by":"publisher","DOI":"10.5555\/574107"},{"key":"e_1_3_2_11_1","doi-asserted-by":"publisher","DOI":"10.1145\/3313831.3376394"},{"key":"e_1_3_2_12_1","series-title":"(ICVSE \u201924)","volume-title":"Proceedings of Eye of the Future: Integrating Computer Vision in Smart Eyewear (ICVSE) Workshop at ECCV 2024","author":"Duchowski Andrew\u00a0T.","year":"2024","unstructured":"Andrew\u00a0T. Duchowski, Krzysztof Krejtz, and Izabela Krejtz. 2024. Real-Time 2nd-order Gaze Metrics. In Proceedings of Eye of the Future: Integrating Computer Vision in Smart Eyewear (ICVSE) Workshop at ECCV 2024 (Milan, Italy) (ICVSE \u201924)."},{"key":"e_1_3_2_13_1","doi-asserted-by":"publisher","DOI":"10.1145\/3173574.3173856"},{"key":"e_1_3_2_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0042-6989(03)00084-1"},{"key":"e_1_3_2_15_1","doi-asserted-by":"publisher","DOI":"10.3389\/jcm12051957"},{"key":"e_1_3_2_16_1","volume-title":"Generalized Additive Models","author":"Hastie Trevor\u00a0J.","year":"1990","unstructured":"Trevor\u00a0J. Hastie and Robert\u00a0J. Tibshirani. 1990. Generalized Additive Models. Chapman & Hall \/ CRC Press."},{"key":"e_1_3_2_17_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.procs.2022.09.189"},{"key":"e_1_3_2_18_1","article-title":"Method and Apparatus for Eye Tracking Monitoring Pupil Dilation to Evaluate Cognitive Activity","author":"Marshall Sandra\u00a0P.","year":"2000","unstructured":"Sandra\u00a0P. Marshall. 2000. Method and Apparatus for Eye Tracking Monitoring Pupil Dilation to Evaluate Cognitive Activity. US Patent No.\u00a06,090,051.","journal-title":"US Patent No.\u00a06,090,051"},{"key":"e_1_3_2_19_1","doi-asserted-by":"publisher","DOI":"10.1109\/HFPP.2002.1042860"},{"issue":"5","key":"e_1_3_2_20_1","first-page":"B165\u2013B175(11)","article-title":"Identifying Cognitive State from Eye Metrics","volume":"78","author":"Marshall Sandra\u00a0P.","year":"2007","unstructured":"Sandra\u00a0P. Marshall. 2007. Identifying Cognitive State from Eye Metrics. Aviation, Space, and Environmental Medicine 78, 5, Seciton II (May 2007), B165\u2013B175(11). Supplement 1.","journal-title":"Aviation, Space, and Environmental Medicine"},{"key":"e_1_3_2_21_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0183723"},{"key":"e_1_3_2_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpsycho.2015.04.019"},{"key":"e_1_3_2_23_1","volume-title":"R: A Language and Environment for Statistical Computing","author":"Team R Core","year":"2021","unstructured":"R Core Team. 2021. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria. https:\/\/www.R-project.org\/"},{"issue":"1","key":"e_1_3_2_24_1","first-page":"1","article-title":"Task difficulty in mental arithmetic affects microsaccadic rates and magnitudes","volume":"39","author":"Siegenthaler Eva","year":"2014","unstructured":"Eva Siegenthaler, Francisco\u00a0M. Costela, Michael\u00a0B. McCamy, Leandro\u00a0L. Di Stasi, Jorge Otero-Millan, Andreas Sonderegger, Rudolf Groner, Stephen Macknik, and Susana Martinez-Conde. 2014. Task difficulty in mental arithmetic affects microsaccadic rates and magnitudes. European Journal of Neuroscience 39, 1 (2014), 1\u20138.","journal-title":"European Journal of Neuroscience"},{"key":"e_1_3_2_25_1","doi-asserted-by":"publisher","DOI":"10.1038\/182857a0"},{"key":"e_1_3_2_26_1","doi-asserted-by":"publisher","DOI":"10.1167\/iovs.16-20785"},{"key":"e_1_3_2_27_1","doi-asserted-by":"publisher","DOI":"10.1080\/001401397187441"},{"key":"e_1_3_2_28_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-statistics-112723-034249"},{"key":"e_1_3_2_29_1","unstructured":"xAI. 2025. Grok: An Artificial Intelligence Model for Scientific and Technical Assistance. https:\/\/x.ai\/grok Version accessed: August 2025."}],"container-title":["Proceedings of the ACM on Computer Graphics and Interactive Techniques"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dl.acm.org\/doi\/pdf\/10.1145\/3803537","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T13:02:59Z","timestamp":1777640579000},"score":1,"resource":{"primary":{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3803537"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,1]]},"references-count":28,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,6,1]]}},"alternative-id":["10.1145\/3803537"],"URL":"https:\/\/doi.org\/10.1145\/3803537","relation":{},"ISSN":["2577-6193"],"issn-type":[{"value":"2577-6193","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,1]]},"assertion":[{"value":"2026-05-01","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}