Trial reportEye (London, England)2017
Caffeine intake is associated with pupil dilation and enhanced accommodation.
Trial report in Eye (London, England), 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT07625358 (Investigating the Effect of Caffeine and Alcohol on Pupil Dynamics), which is not on this map. Cited by 25 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Investigating the Effect of Caffeine and Alcohol on Pupil Dynamics (PAC)
Who cites it
25 citing papers in PubMed, 2 syntheses or guidelines pooled it, 70 citations in OpenAlex.
- Prevalence of non-strabismic binocular vision anomalies and age-related changes in binocular vision among middle-aged and older adults: a systematic review.BMC ophthalmology · 2025Pooled it
- Effects of caffeine intake on pupillary parameters in humans: a systematic review and meta-analysis.Behavioral and brain functions : BBF · 2024Pooled it
- Can Rhodiola rosea supplementation mitigate digital eye strain? A triple-blinded placebo-controlled study.Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) · 2025Trial
- Acute Effects of Caffeine on Ocular Functions in Young Adults.Turkish journal of ophthalmology · 2026Article
- Application of the Kelvin-Voigt viscoelastic model to hippus reveals major insights into the autonomic nervous system activity.Scientific reports · 2026Article
- The pupillary respiratory-phase response: pupil size is smallest around inhalation onset and largest during exhalation.The Journal of physiology · 2025Article
- There Is Significant Within-Subject Variation in the Time from Light Stimulus to Maximum Pupil Constriction Among Healthy Controls.Journal of clinical medicine · 2024Article
- Regulation of pupil size in natural vision across the human lifespan.Royal Society open science · 2024Article
- A Review of the Use of Gaze and Pupil Metrics to Assess Mental Workload in Gamified and Simulated Sensorimotor Tasks.Sensors (Basel, Switzerland) · 2024Review
- Pupil light reflex in young elite athletes: autonomic nervous system activity and viscoelastic properties.Frontiers in physiology · 2024Article
- Revealing the Acute Effects of Dietary Components on Mood and Cognition: The Role of Autonomic Nervous System Responses.Brain sciences · 2023Review
- A time slice analysis of dentistry students' visual search strategies and pupil dilation during diagnosing radiographs.PloS one · 2023Article
- Manipulating expectancies in optometry practice: Ocular accommodation and stereoacuity are sensitive to placebo and nocebo effects.Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) · 2022Article
- Bi-directional Refractive Compensation for With-the-Rule and Against-the-Rule Astigmatism in Young Adults.Investigative ophthalmology & visual science · 2022Article
- Individual pupil size changes as a robust indicator of cognitive familiarity differences.PloS one · 2022Article
- Changes in accommodation dynamics after alcohol consumption, for two different doses.Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie · 2021Article
- Pupillary Responses for Cognitive Load Measurement to Classify Difficulty Levels in an Educational Video Game: Empirical Study.JMIR serious games · 2021Article
- Combined Gaze Metrics as Stress-Sensitive Indicators of Microsurgical Proficiency.Surgical innovation · 2020Article
- Uncharacteristic Task-Evoked Pupillary Responses Implicate Atypical Locus Ceruleus Activity in Autism.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2020Article
- Caffeine Delays Retinal Neurovascular Coupling during Dark to Light Adaptation in Healthy Eyes Revealed by Optical Coherence Tomography Angiography.Investigative ophthalmology & visual science · 2020Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
PurposeIt is purported that caffeine, an autonomic stimulant, affects visual performance. This study sought to assess whether caffeine intake was associated with changes in pupil size and/or amplitude of accommodation.Patients and methodsA double-masked, crossover study was conducted in 50 healthy subjects of age range 19 to 25 years. Subjects were randomized to treatments such that subjects consumed either 250 mg caffeine drink or vehicle on separate days. Amplitude of accommodation was measured by the push-up technique, and pupil size using a millimeter ruler fixed to a slit lamp biomicroscope in dim illumination (5 lux). Amplitude of accommodation and pupil size were taken at baseline, and at 30, 60 and 90 min time points post treatment. Repeated measures one-way ANOVA and paired t-test were used in analyzing data.ResultsAmplitude of accommodation and pupil size after caffeine intake were significantly greater than vehicle (P<0.001) at each time point. Consumption of the caffeine beverage was associated with significant increases in amplitude of accommodation and pupil size with time (P<0.001). Amplitude of accommodation rose from 12.4 (±2.2 D) at baseline to 15.8(±2.6 D) at 90 min. Similarly, pupil size increased from 3.4 (±0.4 mm) at baseline to 4.5 (±0.72 mm) at 90 min. Consumption of vehicle was not associated with increase in amplitude of accommodation or pupil size with time.ConclusionPupil size and accommodation are affected after ingestion of caffeine. This study suggests caffeine may have some influence on visual functions.
Indexed as
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.