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Construction work is associated with high risks of fatalities. Effective, deep and lasting learning from incidents is important for the safety of employees, but not well developed in the construction sector. We studied the organizational processes after a fatality through an auto-ethnographic field work study and found three distinct, but interrelated processes to normalize construction work; juridical, ethical and operational processes. Balanced attention to all three processes supports an effective, deep and lasting learning from incidents. We contribute to the learning from incidents literature with the insight that balanced attention for all three processes helps to learn from incidents and to improve the safety of workers. Furthermore, second victims can be important for the learning of incidents process. Finally, the findings throw new light on inadequate supervision of safety procedures, as the temporary characteristics of projects forces workers to deviate from safety procedures., Design & Construction Management

Development of visuospatial attention can be quantified from infancy onward using visually-guided eye movement responses. We investigated the interaction between eye movement response times and salience in target areas of visual stimuli over age in a cohort of typically developing children. A preferential looking (PL) paradigm consisting of stimuli with six different visual modalities (cartoons, contrast, form, local motion, color, global motion) was combined with the automated measurement of reflexive eye movements. Effective salience was defined as visual salience of each target area relative to its background. Three classes of PL stimuli were used: with high(cartoon, contrast), intermediate-(local motion, form), and low-effective salience (global motion, color). Eye movement response times to the target areas of the six PL stimuli were nonverbally assessed in 220 children aged 1-12 years. The development of response times with age was influenced by effective salience: Response times to targets with high salience reached stable values earlier in development (around 4 years of age) than to targets with low salience (around 9 years of age). Intra-individual response time variability was highest for low-salient stimuli, and stabilized later (around 4 years) than for highly salient stimuli (2 years). The improvement of eye movement response times to visual modalities in PL stimuli occurred earlier in development for highly salient than for low-salient targets. The present age-dependent and salience-related results provide a quantitative and theoretical framework to assess the development of visuospatial attention, and of related visual processing capacities, in children from 1 year of age.

Purpose. To determine how different grades of cataract affect sensitivity threshold and saccadic reaction time (SRT) in eye movement perimetry (EMP). Methods. In EMP, the visual field is tested by assessing the saccades that a subject makes towards peripheral stimuli using an eye tracker. Forty-eight cataract patients underwent pre- and postoperative EMP examination in both eyes. The subjects had to fix a central stimulus presented on the eye tracker monitor and to look at any detected peripheral stimulus upon its appearance. A multilevel mixed model was used to determine the factors that affected the sensitivity threshold and the SRT as a function of cataract grade. Results. We found no effect of cataract severity (LOCS III grades I through IV) on SRT and the sensitivity thresholds. In cataract of LOCS III grade V, however, we found an increase by 27% and 21% (P < 0.001), respectively, compared to the SRT and the sensitivity threshold in LOCS III grade I. Eyes that underwent cataract surgery showed no change in mean SRTs and sensitivity thresholds after surgery in LOCS III grade IV and lower. Conclusion. The present study shows that EMP can be readily used in patients with cataract with LOCS III grade IV and below.

Background: From the need for a quantitative method to examine visual processing in young children, we measured ocular orienting responses to visual stimuli (form, motion, expansion, color, contrast, cartoons). Reliability and applicability of this method were assessed. New method: 80 children (1-12 years) with visual impairments and a reference group of 118 typically developing children (1-6 years) completed two sessions. Test-retest reliability was measured by calculating differences in reaction time and fixation accuracy between the two sessions. For applicability, the cumulative percentage of children that fell within a pre-defined reliability interval was plotted against the mean number of responses. Results: In typically developing children none of the outcome measures significantly differed between sessions. In the children with visual impairments similar results were obtained, except for motion. This stimulus elicited significantly faster reaction times in the second session. In at least 80% of the children reliable reaction times could be calculated if 4 responses to a cartoon stimulus and 1 or 2 responses to the other stimuli were measured. Comparison with existing method(s): The existing method to quantify visual information processing has been refined: the range of visual functions was extended and a criterion for reliable assessment of orienting response times was established. Conclusions: Objective measurement of orienting responses is a reliable method to test the initial stage of visual processing in children with and without visual impairments. A set minimum number of responses for each stimulus warrants the reliability of measurements obtained with this functional method in clinical practice. (C) 2014 Elsevier B.V. All rights reserved.

The three-dimensional vestibulo-ocular reflex (3D VOR) ideally generates compensatory ocular rotations not only with a magnitude equal and opposite to the head rotation but also about an axis that is collinear with the head rotation axis. Vestibulo-ocular responses only partially fulfill this ideal behavior. Because animal studies have shown that vestibular stimulation about particular axes may lead to suboptimal compensatory responses, we investigated in healthy subjects the peaks and troughs in 3D VOR stabilization in terms of gain and alignment of the 3D vestibulo-ocular response. Six healthy upright sitting subjects underwent whole body small amplitude sinusoidal and constant acceleration transients delivered by a six-degree-of-freedom motion platform. Subjects were oscillated about the vertical axis and about axes in the horizontal plane varying between roll and pitch at increments of 22.5A degrees in azimuth. Transients were delivered in yaw, roll, and pitch and in the vertical canal planes. Eye movements were recorded in with 3D search coils. Eye coil signals were converted to rotation vectors, from which we calculated gain and misalignment. During horizontal axis stimulation, systematic deviations were found. In the light, misalignment of the 3D VOR had a maximum misalignment at about 45A degrees. These deviations in misalignment can be explained by vector summation of the eye rotation components with a low gain for torsion and high gain for vertical. In the dark and in response to transients, gain of all components had lower values. Misalignment in darkness and for transients had different peaks and troughs than in the light: its minimum was during pitch axis stimulation and its maximum during roll axis stimulation. We show that the relatively large misalignment for roll in darkness is due to a horizontal eye movement component that is only present in darkness. In combination with the relatively low torsion gain, this horizontal component has a relative lar