Artificial Vision System on Digital Devices for Real-Time Head Tilt Control.

It is common to see cases in which, when performing tasks in close vision in front of a digital screen, the posture or position of the head is not adequate, especially in young people; it is essential to have a correct posture of the head to avoid visual, muscular, or joint problems. Most of the current systems to control head inclination require an external part attached to the subject's head. The aim of this study is the validation of a procedure that, through a detection algorithm and eye tracking, can control the correct position of the head in real time when subjects are in front of a digital device. The system only needs a digital device with a CCD receiver and downloadable software through which we can detect the inclination of the head, indicating if a bad posture is adopted due to a visual problem or simply inadequate visual-postural habits, alerting us to the postural anomaly to correct it.The system was evaluated in subjects with disparate interpupillary distances, at different working distances in front of the digital device, and at each distance, different tilt angles were evaluated. The system evaluated favorably in different lighting environments, correctly detecting the subjects' pupils. The results showed that for most of the variables, particularly good absolute and relative reliability values were found when measuring head tilt with lower accuracy than most of the existing systems. The evaluated results have been positive, making it a considerably inexpensive and easily affordable system for all users. It is the first application capable of measuring the head tilt of the subject at their working or reading distance in real time by tracking their eyes.

Predicción del Síndrome Informático Visual mediante la adicción a videojuegos en estudiantes chinos y españoles / Prediction of computer vision syndrome by video game addiction in Chinese and Spanish students

Introducción: El uso de los videojuegos, por la extensión que ha llegado a alcanzar durante la pandemia de la COVID-19, es una variable relevante de estudio, especialmente por sus interacciones con aspectos de la salud mental y visual. Objetivo: predecir el nivel de Síndrome informático visual a partir de un índice optimizado sobre el nivel de adicción en estudiantes universitarios de dos poblaciones: española y china. Material y Métodos: Se administró un cuestionario online con tres instrumentos validados: un cuestionario para evaluar el juego con videojuegos (CHCVI), un cuestionario para evaluar la adicción a los videojuegos (CERV) y un cuestionario para detectar el síndrome visual por ordenador (CSQ). Los tres cuestionarios se aplicaron a una muestra de 253 estudiantes, tanto de universidades chinas como españolas. Para establecer las predicciones, se construyeron índices robustos basados en el análisis factorial de los instrumentos administrados. Finalmente, se aplicó una regresión logística para obtener un modelo matemático útil para predecir el Síndrome Informático Visual. Resultados: Los resultados mostraron un mayor síndrome informático visual y apetito por los videojuegos en los estudiantes españoles, y menores puntuaciones de síndrome informático visual pero una mayor alteración de la vida cotidiana en los estudiantes chinos debido a este tipo de ocio. Además, se comprobó que los estudiantes de la muestra china tenían un menor riesgo de padecer el síndrome informático visual, y que tener mayores niveles de adicción implicaba 1,4 veces más probabilidades de sufrir dicho síndrome. Conclusiones: Los presentes hallazgos demuestran una relación hasta ahora inexplorada entre la adicción a los videojuegos y los síntomas visuales relacionados con el abuso del ocio electrónico.

Introduction: The use of video games, due to the extent that it has reached during the COVID-19 pandemic, is a relevant study variable especially because of its interactions with aspects of mental and visual health. Objective: to predict the occurrence of computer vision syndrome according to the level of addiction to video games in university undergraduates during a particular period of uncertainty due to health and mobility restrictions imposed by governments as a result of the COVID-19 pandemic. Material and Methods: To accomplish this objective, an online questionnaire was administered with three validated instruments: a questionnaire to assess playing video games (CHCVI), a questionnaire to evaluate video games addiction (CERV), and a questionnaire to detect computer vision syndrome (CSQ). The three questionnaires were applied to a sample of 253 students from both Chinese and Spanish universities. To establish the predictions, robust indexes were constructed based on the Factor Analysis of the instruments administered. Finally, logistic regression was applied to predict computer vision syndrome. Results: The results showed greater computer vision syndrome and appetite for video games in Spanish students, and lower computer vision syndrome scores but a greater alteration of daily life in chinese students due to this type of leisure. Moreover, it was found that students from the Chinese sample entailed a lower risk of suffering from computer vision syndrome, and that having higher levels of addiction involved 1,4 times more likelihood of suffering from such syndrome. Conclusions: The present findings demonstrate a previously unexplored relationship between video games addiction and visual symptoms related to screen exposure.

Air shooting competition effects on visual skills depending on the sport level.

Olympic shooting is a sport with high demands of accuracy. Minimal visual errors could be related to performance losses. However, not all visual skills have been studied in depth in this sport. The main objectives of this study were to compare differences in shooters' visual skills by level and to analyze the competition effect on them. Sixty-six participants were distributed in three groups (non-athletes, elite and non-elite). Eleven visual variables were tested in four skills groups (visual acuity, heterophoria, accommodation functions and other visual skills). The data were collected through a pre- and post-competition simulation test. The results of the study showed differences between groups by shooting sport level. In general, shooters had higher visual acuity values than non-athletes p < .001 with large size effects (d between 1.01 and 2.35), and elite shooters presented higher values of accommodation than non-elite shooters p < .05 with large size effects (d between 0.88 and 0.97). Furthermore, different visual skills were modified after competition depending on the shooting level. Specifically, visual accommodation skills were only improved in elite shooters. Finally, our study suggests that elite shooters employ different visual strategies or skills to non-elite shooters and that shooting activity is closely related to some specific visual skills. This aspect should be considered by coaches in the design of optimal visual trainings and improve the shooters' performance.Highlights Shooters showed better acuity skills than non-athletes.Shooting activity seems to improve visual acuity skills, binocular visual time and eye-hand coordination in non-elite shooters, and accommodation and eye-hand coordination in elite shooters immediately after the competition simulation.Elite shooters employ different visual strategies or skills to non-elite shooters.Non-dominant eye occlusion may benefit binocular vision recovery by inhibiting aiming action and the use of accommodative flexibility could be related to the QE during the shot.

The Influence of COVID-19 Isolation on Physical Activity Habits and Its Relationship with Convergence Insufficiency.

The purpose of this work is to evaluate the effects of confinement due to COVID-19 isolation on visual function, considering insufficient convergence as one of the possible effects of living the whole day in a reduced space. We pass a Convergence Insufficiency Symptom Survey (CISS) among 235 people to detect their habits before and after 25 confinement days. The data collection protocol consisted on a Google forms questionnaire included two parts: the first with current data (isolation period) and a second with pre-isolation period data. Differences between the pre-isolation and isolation period were calculated using the related paired T-tests. When statistically significant differences were found, the effect size was estimated using the Cohen's d index (d). The reduction in physical activity levels during confinement were related to the increase in total number of minutes of screen consumption from 433.49 min to 623.97 min per day (d = 0.67; 44.01%). The CISS scores were increased by more than 43% during confinement. The increase in convergence insufficiency was 100% after the studied isolation period of 25 days. The 92.19% increase in television use during 25 days of confinement is not responsible for the increase in convergence insufficiency. However, due to the increase in the use of PCs in this period, there is a notable increase in convergence insufficiency. Therefore, we can conclude that not all increases in tasks with electronic devices are responsible for the increase in convergence insufficiency.