The present study investigates individual differences in pupil dilation during standard word naming. We looked at (i) how individual subjects’ pupil size changes over the course of time and (ii) how well pupil size is predicted by the frequency of the stimuli. The time course of the pupil size was analysed with generalized additive modeling. The results show large individual variations in the p...

This study proposes a convenient method of evaluating mental stress. The potential of monitoring changes in pupil diameter as a measure of human reliability while operating human-machine systems was examined experimentally. An experiment was carried out to clarify the relation between changes in pupil diameter and autonomic nervous activity by measuring an electrocardiogram and pupil diameter w...

Mammalian retinal photoreceptors form an irradiance detection system that drives many nonvisual responses to light such as pupil reflex and resetting of the circadian clock. To understand the role of pupil size in circadian light responses, pupil diameter was pharmacologically manipulated and the effect on behavioral phase shifts at different irradiance levels was studied in the Syrian hamster....

PURPOSE To observe the changes in pupil size under photopic and scotopic conditions after Implantable Collamer Lens (ICL) implantations in eyes with high myopia. METHODS The ICL was implanted in 90 eyes belonging to 45 patients with high myopia. Photopic pupil diameters, scotopic pupil diameters, anterior chamber depths, and ICL vaults were examined at the preoperative, postoperative 1-month,...

Video-based eye tracking relies on locating pupil center to measure gaze positions. Although widely used, the technique is known to generate spurious gaze position shifts up to several degrees in visual angle because pupil centration can change without eye movement during pupil constriction or dilation. Since pupil size can fluctuate markedly from moment to moment, reflecting arousal state and ...

PURPOSE To evaluate the changes in pupil size after implantation of an iris-supported toric phakic intraocular lens (TPIOL) for correction of myopia and hyperopia with astigmatism. SETTING Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. METHODS Twenty-two myopic eyes and 9 hyperopic eyes were included in the study. The mean age of the 2 groups was 34 years and 40...

PURPOSE To investigate, by high-precision digital analysis of data provided by Scheimpflug imaging, changes in pupil size and shape and anterior chamber (AC) parameters following cataract surgery. PATIENTS AND METHODS The study group (86 eyes, patient age 70.58±10.33 years) was subjected to cataract removal surgery with in-the-bag intraocular lens implantation (pseudophakic). A control group ...

PURPOSE To compare visual and pupil afferent function in dominant optic atrophy (DOA). METHODS Patients with DOA who belonged to families showing evidence of linkage to the locus on chromosome 3q28-qter were recruited from the Moorfields Genetic Register. Patients and healthy control subjects underwent visual and pupil perimetry using a modified automated perimeter (Octopus 1-2-3; Interzeag, ...

This paper proposes a novel pupil and glint detection method for gaze tracking system using a wearable camera sensor and near-infrared LED array. A novel circular ring rays location (CRRL) method is proposed for pupil boundary points detection. Firstly, improved Otsu optimal threshold binarization, opening-and-closing operation and projection of 3D gray-level histogram are utilized to estimate ...

We report a case of unilateral tonic pupil in spinocerebellar ataxia without brainstem atrophy in a 42year-old man. On neurological examination, he showed cerebellar symptoms and unilateral tonic pupil. Deep tendon reflexes were normal except for brisk patellar tendon reflexes. Brain MRI demonstrated cerebellar atrophy only. There was neither orthostatic hypotension nor bowel and bladder failur...