scholarly journals Dynamic visual acuity: Normative functions and practical implications

1987 ◽  
Vol 25 (4) ◽  
pp. 253-256 ◽  
Author(s):  
Gerald M. Long ◽  
David L. Penn
Keyword(s):  
Visual Acuity ◽  
Dynamic Visual Acuity ◽  
Practical Implications

The Effects of Target Borders on Dynamic Visual Acuity: Practical and Theoretical Implications

Perception ◽  
1988 ◽  
Vol 17 (6) ◽  
pp. 745-751 ◽  
Author(s):  
Gerald M Long ◽  
Philip M Garvey
Keyword(s):  
Visual Acuity ◽  
Spatial Frequency ◽  
Frequency Component ◽  
Neural Mechanisms ◽  
Moving Targets ◽  
Dynamic Visual Acuity ◽  
Stimulus Energy ◽  
Spatial Frequency Component ◽  
Slow Moving ◽  
Practical Implications

The effects of target borders on the ability of observers to resolve moving targets (Landolt Cs) under a range of conditions were examined. Contrary to reported findings with stationary targets, it was predicted that the presence of borders would improve acuity for slow-moving targets because (i) overall stimulus energy is kept relatively constant as target detail varies, and (ii) a low-spatial-frequency component is held constant as target detail varies. In an experiment in which a two-sided border (above and below the target) was used, the predicted beneficial effect of the border at slow speeds was obtained. The results are discussed in terms of practical implications for the assessment of dynamic visual acuity as well as the potential neural mechanisms underlying performance.

Dynamic visual acuity in an applied setting.

1961 ◽  
Author(s):  
James E. Goodson ◽  
James W. Miller
Keyword(s):  
Visual Acuity ◽  
Dynamic Visual Acuity

An Investigation of Effects of Contrast, and Linear Velocity upon Dynamic Visual Acuity

1975 ◽  
Vol 19 (3) ◽  
pp. 305-309
Author(s):  
Malireddy R. Reddy
Keyword(s):  
Visual Acuity ◽  
Marked Decrease ◽  
Linear Velocity ◽  
Target Size ◽  
Viewing Time ◽  
Dynamic Visual Acuity ◽  
Industrial Inspection ◽  
Inspection Tasks ◽  
Background Contrast

Variables affecting Dynamic Visual Acuity are important in the design of industrial inspection tasks. The objective of the present study was to investigate the effects of target-background contrast, target size, and linear velocity upon DVA. Photographed block landolt rings were placed on white and grey backgrounds to produce ten uniformly graded contrast levels between target and background. These were then mounted on standard 35 mm photographic slide frames (2 in. x 2 in.). Gaps in the rings were oriented toward the corners of the frames. For a given viewing time, an increase in linear velocity resulted in a marked decrease in DVA ability. Also, for a given linear velocity, an increase in viewing time resulted in an increase in DVA ability. Contrast levels and display width also affected performance.

scholarly journals Sport-specific differences in dynamic visual acuity and gaze stabilization in division-I collegiate athletes

2020 ◽  
Vol 30 (4) ◽  
pp. 249-257
Author(s):  
C. Quintana ◽  
N.R. Heebner ◽  
A.D. Olson ◽  
J.P. Abt ◽  
M.C. Hoch
Keyword(s):  
Visual Acuity ◽  
A Priori ◽  
Collegiate Athletes ◽  
Division I ◽  
Normative Values ◽  
Dynamic Visual Acuity ◽  
Gaze Stabilization ◽  
Concussion Management ◽  
Vestibular Ocular Reflex ◽  
Concussion History

BACKGROUND: The vestibular-ocular reflex (VOR) integrates the vestibular and ocular systems to maintain gaze during head motion. This reflex is often negatively affected following sport-related concussion. Objective measures of gaze stability, a function mediated by the VOR, such as the computerized dynamic visual acuity test (DVAT) and gaze stabilization test (GST), may have utility in concussion management. However, normative data specific to sport, sex, or concussion history have not been established in collegiate athletes. OBJECTIVE: The objective of this study was to establish normative values for the DVAT and GST in collegiate athletes and explore the effect of sport, sex, and concussion history on VOR assessments. METHODS: The DVAT and GST were completed by 124 collegiate athletes (72 male, 52 female, mean±SD, age: 19.71±1.74 years, height: 173.99±13.97 cm, weight: 80.06±26.52 kg) recruited from Division-I athletic teams (football, soccer and cheerleading). The DVAT and GST were performed in the rightward and leftward directions during a single session in a standardized environment. Normative values for DVAT and GST measures were expressed as percentiles. Non-parametric statistics were used to compare differences between groups based on sex, sport, and concussion history. Alpha was set a-priori at 0.05. RESULTS: Overall, the median LogMAR unit for 124 athletes completing the DVAT was 0 (IQR = 0.17) for both leftward and rightward. The median velocities achieved on the GST were 145 °/sec and 150 °/sec (IQR = 45 and 40) for the leftward and rightward directions respectively. Significant differences were observed between sports (p = 0.001–0.17) for the GST with cheerleading demonstrating higher velocities than the other sports. However, no significant differences were identified based on sex (p≥0.09) or history of concussion (p≥0.15). CONCLUSIONS: Normative estimates for the DVAT and GST may assist in the clinical interpretation of outcomes when used in post-concussion evaluation for collegiate athletes. Although sex and previous concussion history had no effect on the DVAT or GST, performance on these measures may be influenced by type of sport. Sport-related differences in the GST may reflect VOR adaptations based on individual sport-specific demands.

Effect of oculo-motor and gaze stability exercises on postural stability and dynamic visual acuity in healthy young adults

2011 ◽  
Vol 33 (4) ◽  
pp. 600-603 ◽  
Author(s):  
Hiroyuki Morimoto ◽  
Yuji Asai ◽  
Eric G. Johnson ◽  
Everett B. Lohman ◽  
Keiko Khoo ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Young Adults ◽  
Postural Stability ◽  
Dynamic Visual Acuity ◽  
Gaze Stability
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