Processing of transient signals in the visual system of the European starling (Sturnusvulgaris) and humans

The double-pulse resolution (DPR) measures the processing performance for transient visual signals as the threshold duration for detecting a temporal gap between two light flashes in relation to gap duration. The DPR of four European starlings (Sturnus vulgaris) and four humans was measured in an operant Go/NoGo procedure. We applied the method of constant stimuli and determined thresholds using signal-detection theory. The starling DPR (22.2 ms ± 2.3 ms SE) was significantly shorter than human DPR (35.2 ms ± 1.3 ms SE; p < 0.01, t-test). The difference suggests that starlings have a higher temporal resolution for transient visual signals than humans.     

To prescribe or not to prescribe? Guidelines for spectacle prescribing in infants and children

This paper discusses the considerations for prescribing a refractive correction in infants and children up to and including school age, with reference to the current literature. The focus is on children who do not have other disorders, for example, binocular vision anomalies, such as strabismus, significant heterophoria or convergence excess. However, refractive amblyogenic factors are discussed, as is prescribing for refractive amblyopia. Based on this discussion, guidelines are proposed, which indicate when to prescribe spectacles and what amount of refractive error should be corrected. It may be argued that these are premature because there are many questions that remain unanswered and we do not have the quality of evidence that we would like; the clinician, however, must make decisions on whether and what to prescribe when examining a child. These guidelines are to aid clinicians in their current clinical decision making.     

先天性上斜肌麻痹与双眼视觉

先天性上斜肌麻痹是先天性眼肌麻痹中较为常见的类型。双眼视觉与生活息息相关,立体视觉和深度知觉丧失会使患者不能涉及许多需要精细目力的工作,影响生活质量,本文就先天性上斜肌麻痹与双眼视觉作一综述。     

Experimental study of visual training effects in shooting initiation

Introduction : The present study was conducted to investigate the influence of specific visual training in shooting initiation performance. Methods : Seventy-one first-year university students were divided randomly into two groups. The experimental group followed a nine-session shooting training program that included technical, physical and psychological components, along with specific visual exercises. The control group followed the same program with one difference: this group received theoretical lectures on psychological training techniques instead of doing visual exercises. Pre- and post-test results were obtained for shooting, concentration, saccades and visual acuity. Results : Statistical analysis indicated significant gains in the four mentioned variables for the experimental group. The control group also showed significant differences in the three first variables but no significant improvement in visual acuity. No significant differences in shooting performance were observed between groups. Conclusions : The effect of vision training on sports initiation performance is still not clear. It cannot be assumed that the improvement is transferable to the performance of precision shooting at the stage of sports initiation.     

视觉模糊成因及自我康复要领

本文从整体生命观分析视觉模糊的成因,意识、形体、呼吸、眼睛等紧张及不良用眼习惯导致视觉模糊,自我康复需重建健康的生命运动模式,保持松静自然,集中专一,练养结合,恢复正常视觉功能。