A PRELIMINARY STUDY ON PUPIL SIZE CHANGES DETECTION ON MENTAL STRESS WITH MENTAL STRESSOR

2017 ◽  
Vol 29 (02) ◽  
pp. 1750011
Author(s):  
Poh Foong Lee ◽  
Khai Shan Lee
Keyword(s):  
Pupil Size ◽  
Pupil Diameter ◽  
Detection Algorithm ◽  
Pupil Dilation ◽  
Simple Tool ◽  
Pupil Detection ◽  
Acquisition Device ◽  
Changes Detection ◽  
Proportional Relationship ◽  
Preliminary Study

This is a study on measuring the effect of stress that stimulated by the different difficulty of game level on pupil dilation. Playing games are claimed a method to distress in the community, however, this activity is enhancing stress level? The effect of the game playing on the changes of pupil dilation is unknown. An investigation was conducted on relating the changes of pupil diameter measurement at the different difficulty levels of the game. A simple tool was developed by using a webcam as image acquisition device together with MATLAB Image Processing Tool to analyze the acquired images. Here, experiments on the pupil detection algorithm, which consisted of four different methods are to work alternatively with one another and to provide higher chances of pupil detection. 10 subjects were involved in the experiments, which they were requested to play a selected game with four different ascending increased in difficulties, meanwhile, pupil size changes were measured simultaneously. The selected game served as a stress stimulus to the subjects. The result showed a positive proportional relationship between increased in game difficulty levels and pupil dilation. The investigation reported that the pupil dilated when the difficulty of game level increased. Limitation of this study is the sample size on the prototype testing should be increased to concrete the outcome.

Effects of Photo-Depicted Pupil Diameter on Judgments of Others’ Attentiveness and on Facial Recognition Memory

2016 ◽  
Vol 124 (2) ◽  
pp. 366-379
Author(s):  
Nicholas Watier ◽  
Christopher Healy ◽  
Heather Armstrong
Keyword(s):  
Face Recognition ◽  
Recognition Memory ◽  
Personnel Selection ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Facial Recognition ◽  
Memory Performance ◽  
Preliminary Evidence ◽  
Recognition Memory Performance ◽  
Preliminary Study

Occasionally, individuals perceive that someone is no longer paying attention to the discussion at hand even when there are no overt cues of inattentiveness. As a preliminary study of this phenomenon, we examined whether pupil diameter might be implicitly used to infer others’ attentiveness. Forty participants (27 women, 13 men, M age = 19.7 year, SD = 2.8) were presented with images of male faces with either large or small pupils, and, in the context of a personnel selection scenario, participants then judged the attentiveness of the person in the image. Images of faces with large pupils were judged as more attentive, compared with images of faces with small pupils. Face recognition memory performance was not affected by depicted pupil size. Our results are consistent with the proposal that pupillary fluctuations can be an index of perceived attention, and they provide preliminary evidence that pupil dilation may be implicitly relied upon to infer attentional states.

scholarly journals Autobiographical memory increases pupil dilation

2019 ◽  
Vol 10 (1) ◽  
pp. 280-287
Author(s):  
Mohamad El Haj ◽  
Steve M. J. Janssen ◽  
Karim Gallouj ◽  
Quentin Lenoble
Keyword(s):  
Autobiographical Memory ◽  
Cognitive Processing ◽  
Memory Retrieval ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Emotional Valence ◽  
Pupil Dilation ◽  
Control Task ◽  
Negative Memories

Abstract Background Pupil activity has been widely considered as a “summed index” of physiological activities during cognitive processing. Methodology We investigated pupil dilation during retrieval of autobiographical memory and compared pupil diameter with a control condition in which participants had to count aloud. We also measured pupil diameters retrieval of free (i.e., first memory that comes to mind), positive, and negative memories (memories associated, respectively, with the words “happy” and “sad”). Results Analyses demonstrated larger pupil diameters during the free, positive, and negative autobiographical memory retrieval than during the control task. Analyses also demonstrated no significant differences in pupil diameters across the three autobiographical memory conditions. Conclusion These outcomes demonstrate that, compared with counting, autobiographical retrieval results in a larger pupil size. However, the emotional valence of memories yields non-significant effect on pupil diameters. Our findings demonstrate how autobiographical memory retrieval yields pupil dilation.

scholarly journals Early phase of pupil dilation is mediated by the peripheral parasympathetic pathway

2021 ◽  
Author(s):  
Chinatsu Marumo ◽  
Tamami Nakano
Keyword(s):  
Early Phase ◽  
Untreated Control ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Pupil Dilation ◽  
Sphincter Muscle ◽  
Dilator Muscle ◽  
Brain States ◽  
Parasympathetic Pathway ◽  
Iris Sphincter

Pupil diameter fluctuates in association with changes in brain states induced by the neuromodulator systems. However, it remains unclear how the neuromodulator systems control the activity of the iris sphincter (constrictor) and dilator muscles to change the pupil size. The present study compared temporal patterns of pupil dilation during movement when each muscle was pharmacologically manipulated in the human eye. When the iris sphincter muscle was blocked with tropicamide, the latency of pupil dilation was delayed and the magnitude of pupil dilation was reduced during movement. In contrast, when the iris dilator muscle was continuously stimulated with phenylephrine, the latency and magnitude of rapid pupil dilation did not differ from the untreated control eye, but sustained pupil dilation was reduced until the end of movement. These results suggest that the iris sphincter muscle, which is under the control of the parasympathetic pathway, is quickly modulated by the neuromodulator system and plays a major role in rapid pupil dilation. However, the iris dilator muscle receives signals from the neuromodulator system with a slow latency and is involved in maintaining sustained pupil dilation.

scholarly journals Listener’s personality traits predict changes in pupil size during auditory language comprehension

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Isabell Hubert Lyall ◽  
Juhani Järvikivi
Keyword(s):  
Personality Traits ◽  
Language Processing ◽  
Language Comprehension ◽  
Pupil Size ◽  
Pupil Dilation ◽  
Systematic Research ◽  
Cognitive Resources ◽  
Personality Profiles ◽  
Pupillary Responses ◽  
Grammatical Errors

AbstractResearch suggests that listeners’ comprehension of spoken language is concurrently affected by linguistic and non-linguistic factors, including individual difference factors. However, there is no systematic research on whether general personality traits affect language processing. We correlated 88 native English-speaking participants’ Big-5 traits with their pupillary responses to spoken sentences that included grammatical errors, "He frequently have burgers for dinner"; semantic anomalies, "Dogs sometimes chase teas"; and statements incongruent with gender stereotyped expectations, such as "I sometimes buy my bras at Hudson's Bay", spoken by a male speaker. Generalized additive mixed models showed that the listener's Openness, Extraversion, Agreeableness, and Neuroticism traits modulated resource allocation to the three different types of unexpected stimuli. No personality trait affected changes in pupil size across the board: less open participants showed greater pupil dilation when processing sentences with grammatical errors; and more introverted listeners showed greater pupil dilation in response to both semantic anomalies and socio-cultural clashes. Our study is the first one demonstrating that personality traits systematically modulate listeners’ online language processing. Our results suggest that individuals with different personality profiles exhibit different patterns of the allocation of cognitive resources during real-time language comprehension.

scholarly journals Pupil Dilation with Intracameral Epinephrine Hydrochloride during Phacoemulsification and Intraocular Lens Implantation

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
A-Yong Yu ◽  
Hua Guo ◽  
Qin-Mei Wang ◽  
Fang-Jun Bao ◽  
Jing-Hai Huang
Keyword(s):  
Intraocular Lens ◽  
Pupil Diameter ◽  
Pupil Dilation ◽  
Surgical Performance ◽  
Corneal Incision ◽  
Iol Implantation ◽  
The Mean ◽  
Contralateral Eye ◽  
To Receive ◽  
Time Point

Objective. To investigate mydriatic effect of intracamerally injected epinephrine hydrochloride during phacoemulsification and intraocular lens (IOL) implantation.Methods. Eighteen cataract patients for bilateral phacoemulsification were enrolled. To dilate pupil, one eye was randomly selected to receive intracamerally 1 mL epinephrine hydrochloride 0.001% for 1 minute after corneal incision (intracameral group), and the contralateral eye received 3 drops of compound tropicamide 0.5% and phenylephrine 0.5% at 5-minute intervals 30 minutes before surgery (topical group). Pupil diameters were measured before corneal incision, before ophthalmic viscoelastic device (OVD) injection, after OVD injection, before IOL implantation, and at the end of surgery.Results. At each time point, the mean pupil diameter in the intracameral group was2.20±0.08,5.09±0.20,6.76±0.19,6.48±0.18, and5.97±0.24 mm, respectively, and in the topical group it was7.98±0.15,7.98±0.15,8.53±0.14,8.27±0.16, and7.93±0.20 mm, respectively. The topical group consistently had larger mydriatic effects than the intracameral group (P<0.05). The onset of mydriatic effect was rapid in the intracameral group. There was no difference in surgical performance or other parameters between groups.Conclusions. Intracameral epinephrine hydrochloride appears to be an alternative to the mydriatic modalities for phacoemulsification and IOL implantation. In comparison with topical mydriatics, intracameral epinephrine hydrochloride offers easier preoperative preparation, more rapid pupil dilation, and comparable surgical performance.

Clinical evaluation of the repeatability of ocular aberrometry obtained with a new pyramid wavefront sensor

2018 ◽  
Vol 29 (6) ◽  
pp. 585-592 ◽  
Author(s):  
Ana B Plaza-Puche ◽  
Liberdade C Salerno ◽  
Francesco Versaci ◽  
Daniel Romero ◽  
Jorge L Alio
Keyword(s):  
Standard Deviation ◽  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Intraclass Correlation ◽  
Wavefront Sensor ◽  
Mean Square ◽  
The Subject ◽  
Healthy Eyes

Purpose:To evaluate the intrasubject repeatability of the ocular aberrometry obtained with a new ocular pyramidal aberrometer technology in a sample of normal eyes.Methods:A total of 53 healthy eyes of 53 subjects with ages ranging from 18 to 45 years were included in this study. In all cases, three consecutive acquisitions were obtained. Intrasubject repeatability of the measurements with a pyramidal aberrometer was calculated. Intrasubject repeatability for 4.0- and 6.0-mm pupils was evaluated within the subject standard deviation (Sw) and intraclass correlation coefficient.Results:Low values of the Swand intraclass correlation coefficient outcomes close to 1 were observed for the sphere and cylinder at 3.0-mm pupil size. Most low Swand intraclass correlation coefficient values close to 1 were observed for total, low-order aberrations and higher-order aberrations root mean square and for each Zernike coefficient analysis (intraclass correlation coefficient ⩾0.798) at 4.0-mm pupil size, with more limited outcomes for the aberrometric coefficient of Z(4, 4) with an intraclass correlation coefficient of 0.683. For a 6.0 mm pupil diameter, low Swand intraclass correlation coefficient values close to 1 were observed for all aberrometric parameters or Zernike coefficients analyzed (intraclass correlation coefficient ⩾0.850).Conclusion:The new pyramidal aberrometer Osiris provides repeatable and consistent measurements of ocular aberrometry measurements in normal eyes.

scholarly journals Priming Younger and Older Adults’ Sentence Comprehension: Insights from Dynamic Emotional Facial Expressions and Pupil Size Measures

2016 ◽  
Vol 9 (1) ◽  
pp. 129-148 ◽  
Author(s):  
Maria Nella Carminati ◽  
Pia Knoeferle
Keyword(s):  
Older Adults ◽  
Sentence Processing ◽  
Pupil Size ◽  
Sentence Comprehension ◽  
Cognitive Effort ◽  
Pupil Dilation ◽  
Emotional Facial Expressions ◽  
Visual World ◽  
Positivity Effect ◽  
Positive Valence

Background: Prior visual-world research has demonstrated that emotional priming of spoken sentence processing is rapidly modulated by age. Older and younger participants saw two photographs of a positive and of a negative event side-by-side and listened to a spoken sentence about one of these events. Older adults’ fixations to the mentioned (positive) event were enhanced when the still photograph of a previously-inspected positive-valence speaker face was (vs. wasn’t) emotionally congruent with the event/sentence. By contrast, the younger adults exhibited such an enhancement with negative stimuli only. Objective: The first aim of the current study was to assess the replicability of these findings with dynamic face stimuli (unfolding from neutral to happy or sad). A second goal was to assess a key prediction made by socio-emotional selectivity theory, viz. that the positivity effect (a preference for positive information) displayed by older adults involves cognitive effort. Method: We conducted an eye-tracking visual-world experiment. Results: Most priming and age effects, including the positivity effects, replicated. However, against our expectations, the positive gaze preference in older adults did not co-vary with a standard measure of cognitive effort - increased pupil dilation. Instead, pupil size was significantly bigger when (both younger and older) adults processed negative than positive stimuli. Conclusion: These findings are in line with previous research on the relationship between positive gaze preferences and pupil dilation. We discuss both theoretical and methodological implications of these results.

Accuracy and Fairness in Pupil Detection Algorithm

2021 ◽  
Author(s):  
Omkar N. Kulkarni ◽  
Vikram Patil ◽  
Vivek K. Singh ◽  
Pradeep K. Atrey
Keyword(s):  
Detection Algorithm ◽  
Pupil Detection

Detecting Deception: Effect of Auditory and Visual Stimuli on Pupil Dilation

2019 ◽  
Vol 47 (3) ◽  
pp. 1-10
Author(s):  
Kiho Kim ◽  
Yeonsil Lee ◽  
Hui-Teak Kim ◽  
Jang-Han Lee
Keyword(s):  
Pupil Diameter ◽  
Physiological Responses ◽  
Visual Stimuli ◽  
Lie Detection ◽  
Emotional Arousal ◽  
Pupil Dilation ◽  
Question Type ◽  
Sensory Stimulus ◽  
Eye Tracker ◽  
Control Question

We investigated the effects of auditory and visual stimuli on pupil dilation induced by emotional arousal during deception. The 33 participants were free to select to be in either a guilty or a not-guilty group. The guilty group performed a theft crime mission, and the not-guilty group performed a legal mission. To detect deception, we measured their pupil diameter with an eye tracker, and they completed the Control Question Test that is typically employed in polygraph tests, and which is based on a comparison of physiological responses to crime-relevant questions and comparison questions. This test was presented via one of three stimuli: auditory, visual, or dual sensory (auditory and visual simultaneously). The findings revealed that the diameter of the pupils of the guilty group increased differently according to the question type when both auditory and visual stimuli were presented simultaneously. Results suggest that pupil dilation could be the deception discriminant, and the use of more than one sensory stimulus may support lie detection in forensic investigations.

Anticipation and Stuttering: A Pupillographic Study

1969 ◽  
Vol 12 (4) ◽  
pp. 833-839 ◽  
Author(s):  
Kenneth C. Gray ◽  
Dean E. Williams
Keyword(s):  
Auditory Stimulus ◽  
Pupil Size ◽  
Free Association ◽  
Pupil Dilation ◽  
Auditory Stimuli ◽  
Physiological Changes ◽  
Single Word ◽  
Pupil Response ◽  
Association Response ◽  
Pupil Reaction

Changes in pupil size were studied in 24 stuttering and 30 nonstuttering adults during a 4-sec period following the presentation of single-word auditory stimuli and before a signal to respond. Subjects were required first to respond with a single word which was the opposite of the word presented and later to give a one-word free-association response to words of both emotional and neutral connotations. Pupil size was measured also while subjects merely listened to the word stimuli. The process of attending to an auditory stimulus was associated with pupil dilation. Pupil response was significantly greater (in absolute diameter and in dilation) when subjects were required to give an oral response to the stimulus than when they simply listened to the stimulus. Furthermore, the extent of the pupil reaction was related to the nature of the stimulus presented. Such differences in arousal did not occur to any greater degree in stutterers than in nonstutterers. Moreover, among stutterers, measures of pupil size were not predictive of stuttering. Thus, the cues which the stutterer associates with the anticipation of stuttering do not appear to be reflected in the physiological changes associated with pupillary movement.

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