12 research outputs found
The Relationship between Anxiety, Visual Function, and Symptomatology in University Students
Mental health concerns have emerged at the university level, with the psychological wellbeing
of students being increasingly affected. This cross-sectional study investigated the proportion
of university students having anxiety, and its effects on their visual function and symptomatology. We
included 41 students (26.1 4.8 years), and their visual function was assessed through several tests
to produce a general visual performance index (VPI). The visual symptomatology was studied using
the Conlon Visual Discomfort Survey and the Quality of Vision (QoV) questionnaire. The students
were classified into two groups according to the Generalized Anxiety Disorder Screener (GAD-7)
test (“no anxiety” and “anxiety” groups). The visual function evaluation indicated significantly
worse VPI in the anxiety group (p = 0.047). These students also showed significantly higher scores
in the Conlon survey (p = 0.004) and two subscales of the QoV questionnaire: symptom severity
(p = 0.041) and symptom bothersomeness (p = 0.013). Moreover, the multiple linear regression model
showed a significant association between visual discomfort according to the Conlon questionnaire
and the level of anxiety (r = 0.405; R2 = 0.164; B = 0.405; p = 0.012). It is important to study the
influence of psychological factors on vision, not only for refractive error, but also for binocular and
accommodative disorder
Night-vision tests for evaluating visual performance
1.550 SJR (2011) Q1, 14/103 Ophthalmology; Q2, 12/38 Sensory systems, 38/76 Cellular and molecular neuroscienc
Self-Regulation of Driving Behavior Under the Influence of Cannabis: The Role of Driving Complexity and Driver Vision
OBJECTIVE: This study analyzed the self-regulation behaviors of drivers under the influence of cannabis and its relationship with road complexity and some driver traits, including visual deterioration.BACKGROUND: Cannabis is the illicit drug most often detected in drivers; its use results in significant negative effects in terms of visual function. Self-regulation behaviors involve the mechanisms used by drivers to maintain or reduce the risk resulting from different circumstances or the driving environment.METHODS: Thirty-one young, occasional cannabis users were assessed both in a baseline session and after smoking cannabis. We evaluated the visual function (visual acuity and contrast sensitivity) and driver self-regulation variables of both longitudinal and lateral control as the speed adaptation and standard deviation of lateral position (SDLP).RESULTS: Visual function was significantly impaired after cannabis use. Recreational cannabis use did not result in self-regulation, although some road features such as curved roads did determine self-regulation. Male participants adopted mean faster driving speeds with respect to the speed limit. Driver age also determined better lateral control with lower SDLPs. In addition, visual impairment resulting from cannabis use (contrast sensitivity) was linked with self-regulation by changes in longitudinal and lateral control.CONCLUSION: Contrast sensitivity could be a good indicator of individual visual status to help determine how drivers self-regulate their driving both in normal conditions and while under the influence of cannabis.APPLICATION: The findings provide new insights about driver self-regulation under cannabis effects and are useful for policy making and awareness campaigns.</p
Retinal-Image Quality and Night-Vision Performance after Alcohol Consumption
. Purpose. To evaluate the influence of alcohol consumption on the retinal-image quality and visual performance under surrounding low-illumination conditions. Methods. A volunteer sample of 67 subjects was analyzed. Optical quality of the eye was evaluated by means of the Strehl ratio, the Objective Scattering Index (OSI), and the tear-film quality. We used the visual disturbance index (VDI) to evaluate visual performance under low-illumination conditions and we measured the pupil size under these conditions. The tearfilm volume was also measured. All measurements were made before and after alcohol consumption and patients were classified into two groups depending on their breath alcohol content (BrAC): low-alcohol (BrAC < 0.25 mg/L) and high-alcohol content (BrAC ≥ 0.25 mg/L). Results. The VDI was significantly higher after alcohol consumption: the higher the BrAC, the higher the deterioration of the visual discrimination capacity. The pupil size increased significantly for the high-BrAC group. Parameters evaluating optical quality deteriorated after alcohol consumption. Conclusion. The visual performance under low-illumination conditions and the retinal-image quality were deteriorated after alcohol consumption, especially for the high-alcohol group. Furthermore, some physiological changes were observed under effects for high-alcohol contents, such as an increase in the pupil size and disturbances in the tear film, which deteriorated optical quality
Effects of alcohol consumption on driving performance in the presence of interocular differences simulated by filters
Abstract The role of interocular differences simulated by filters (fog filter and Bangerter foil) on visual and driving performance in alcohol users was assessed. We found that the binocular visual function deteriorates significantly in terms of contrast sensitivity (from 6 to 18 cpd). Additionally, driving performance is significantly impaired under these conditions as evidenced by increased mean speed, standard deviation of the lateral position, distance traveled outside the lane, reaction time and number of collisions. Furthermore, we found that interocular differences due to intraocular scattering and straylight are directly related to an overall reduction in visual and driving performance. This provided a comprehensive perspective from which to understand the relationship between binocular visual function, interocular differences, and driving performance. In practice, our findings contribute to the understanding of the importance of limiting interocular differences, which can be common among presbyopes corrected using the monovision technique, as well as in cases of cataract or other ocular pathology affecting only one eye, or even in cases of cataract surgery of the first eye. These interocular differences can have an adverse impact on road safety, especially when combined with moderate alcohol consumption