Joanne M. Wood

AGE AND VISUAL IMPAIRMENT DECREASE DRIVING PERFORMANCE AS MEASURED ON A CLOSED-ROAD CIRCUIT

In this study the effects of visual impairment and age on driving were investigated and related to visual function. Participants were 139 licensed drivers (young, middle-aged, and older participants with normal vision, and older participants with ocular disease). Driving performance was assessed during the daytime on a closed-road driving circuit. Visual performance was assessed using a vision testing battery. Age and visual impairment had a significant detrimental effect on recognition tasks (detection and recognition of signs and hazards), time to complete driving tasks (overall course time, reversing, and maneuvering), maneuvering ability, divided attention, and an overall driving performance index. All vision measures were significantly affected by group membership. A combination of motion sensitivity, useful field of view (UFOV), Pelli-Robson letter contrast sensitivity, and dynamic acuity could predict 50% of the variance in overall driving scores. These results indicate that older drivers with either normal vision or visual impairment had poorer driving performance compared with younger or middle-aged drivers with normal vision. The inclusion of tests such as motion sensitivity and the UFOV significantly improve the predictive power of vision tests for driving performance. Although such measures may not be practical for widespread screening, their application in selected cases should be considered.

Quantitative assessment of driving performance in Parkinson’s disease

Objectives: The primary aim of this study was to determine how Parkinson’s disease (PD) affects driving performance. It also examined whether changes in driver safety were related to specific clinical disease markers or an individual’s self rating of driving ability. Methods: The driving performance of 25 patients with idiopathic PD and 21 age matched controls was assessed on a standardised open road route by an occupational therapist and driving instructor, to provide overall safety ratings and specific driving error scores. Results: The drivers with PD were rated as significantly less safe (p<0.05) than controls, and more than half of the drivers with PD would not have passed a state based driving test. The driver safety ratings were more strongly related to disease duration (r = −0.60) than to their on time Unified Parkinson’s Disease Rating Scale (r = −0.24). Drivers with PD made significantly more errors than the control group during manoeuvres that involved changing lanes and lane keeping, monitoring their blind spot, reversing, car parking, and traffic light controlled intersections. The driving instructor also had to intervene to avoid an incident significantly more often for drivers with PD than for controls. Interestingly, driver safety ratings were unrelated to an individual’s rating of their own driving performance, and this was the case for all participants. Conclusions: As a group, drivers with PD are less safe to drive than age matched controls. Standard clinical markers cannot reliably predict driver safety. Further studies are required to ascertain whether the identified driving difficulties can be ameliorated.

A multidomain approach for predicting older driver safety under in-traffic road conditions

OBJECTIVES: To identify a battery of tests that predicts safe and unsafe performance on an on‐road assessment of driving.

Elderly drivers and simulated visual impairment

Background. The effect of simulated visual impairment on the driving performance of elderly subjects and the relation between changes in driving performance and vision were investigated. Methods. Vision was impaired by goggles simulating the effects of cataracts, binocular visual field restriction, and monocularity. Driving was assessed on a road circuit free of other vehicles. Visual performance was measured using the Humphrey Field Analyser (HFA), the Useful Field of View (UFOV), and the Pelli-Robson chart. Results. The simulated visual impairment significantly decreased driving performance, even though all drivers satisfied the legal visual requirements for driving. Significant correlations between driving performance and the UFOV and Pelli-Robson chart were found.

The Effect of Amblyopia on Fine Motor Skills in Children

PURPOSE In an investigation of the functional impact of amblyopia in children, the fine motor skills of amblyopes and age-matched control subjects were compared. The influence of visual factors that might predict any decrement in fine motor skills was also explored. METHODS Vision and fine motor skills were tested in a group of children (n = 82; mean age, 8.2 +/- 1.7 [SD] years) with amblyopia of different causes (infantile esotropia, n = 17; acquired strabismus, n = 28; anisometropia, n = 15; mixed, n = 13; and deprivation n = 9), and age-matched control children (n = 37; age 8.3 +/- 1.3 years). Visual motor control (VMC) and upper limb speed and dexterity (ULSD) items of the Bruininks-Oseretsky Test of Motor Proficiency were assessed, and logMAR visual acuity (VA) and Randot stereopsis were measured. Multiple regression models were used to identify the visual determinants of fine motor skills performance. RESULTS Amblyopes performed significantly poorer than control subjects on 9 of 16 fine motor skills subitems and for the overall age-standardized scores for both VMC and ULSD items (P < 0.05). The effects were most evident on timed tasks. The etiology of amblyopia and level of binocular function significantly affected fine motor skill performance on both items; however, when examined in a multiple regression model that took into account the intercorrelation between visual characteristics, poorer fine motor skills performance was associated with strabismus (F(1,75) = 5.428; P = 0.022), but not with the level of binocular function, refractive error, or visual acuity in either eye. CONCLUSIONS Fine motor skills were reduced in children with amblyopia, particularly those with strabismus, compared with control subjects. The deficits in motor performance were greatest on manual dexterity tasks requiring speed and accuracy.

Can the Anticipatory Skills of Experts Be Learned by Novices

(1999). Can the Anticipatory Skills of Experts Be Learned by Novices? Research Quarterly for Exercise and Sport: Vol. 70, No. 3, pp. 313-318.

Effect of restriction of the binocular visual field on driving performance.

The importance of the visual field on driving performance was investigated. This was undertaken by simulating binocular visual field defects for a group of young normal subjects and assessing the impact of these defects on performance on a driving course. Constriction of the binocular visual field to 40° or less, significantly increased time taken to complete the course, reduced the ability to detect and correctly identify road signs, avoid obstacles and lo manoeuvre through limited spaces. Accuracy of road positioning and reversing were also impaired. Constriction of the binocular visual field did not significantly affect speed estimation, stopping distance, or the time taken for the reversing and manoeuvring tasks. The monocular condition did not significantly affect performance for any of the driving tasks assessed.

Do generalized visual training programmes for sport really work? An experimental investigation.

We assessed the effectiveness of two generalized visual training programmes in enhancing visual and motor performance for racquet sports. Forty young participants were assigned equally to groups undertaking visual training using Revien and Gabor’s Sports Vision programme (Group 1), visual training using Revien’s Eyerobics (Group 2), a placebo condition involving reading (Group 3) and a control condition involving physical practice only (Group 4). Measures of basic visual function and of sport-specific motor performance were obtained from all participants before and immediately after a 4-week training period. Significant pre- to post-training differences were evident on some of the measures; however, these were not group-dependent. Contrary to the claims made by proponents of generalized visual training, we found no evidence that the visual training programmes led to improvements in either vision or motor performance above and beyond those resulting simply from test familiarity.

Vistech VCTS 6500 charts--within- and between-session reliability.

The aim of the study was to measure the reliability of the Vistech VCTS 6500 charts, in test score units, in order to allow clinicians to derive estimates of what constitutes a clinically meaningful change in performance over time. The reliability of a more familiar test, Bailey-Lovie high contrast visual acuity, was also measured to provide a comparison. Patients with normal vision and with early or subtle eye disease were recruited so that the results would be representative of the population likely to present for primary vision screening. Patients were tested on all three VCTS charts on two separate occasions at least 3 weeks apart to give estimates of within- and between-session reliability. Reliability was found to be low in all circumstances; between-session reliability could be improved by using the mean score for the three charts, but the 95% range of difference scores still encompassed at least one-half of the total performance range of the test. It was concluded that Vistech charts are unlikely to be of use for clinical measurements or for research studies.

Serial examination of the normal visual field using Octopus automated projection perimetry Evidence for a learning effect

Abstract. The influence of prior perimetric experience on the magnitude of both differential sensitivity and the short and long term fluctuations remains unclear, and confounds accurate interpretation of visual field data obtained by computer‐assisted perimetry. The purpose of the experiment was to identify and quantify any influence of training on the automated perimetric response. The full field of the right eye of 10 clinically normal, naive subjects was examined on 8 occasions with Octopus Program 21 (target size 3) on days 1–5 inclusive, 15, 16 and 44. Sensitivity increased with serial examination in 8 subjects. By dividing the field into zones, it was demonstrated that the learning effect was greatest in the superior field and for eccentricities beyond 30°.