Mechanisms underlying cognitive conspicuity in the detection of cyclists by car drivers.

Objective: The aim of this study was to evaluate the visibility of cyclists for motorists in a simulated car driving task.

Background: In several cases involving collisions between cars and cyclists, car drivers failed to detect the latter in time to avoid collision because of their low conspicuity.

Method: 2 groups of motorists (29.

Effects of shrinkage of the visual field through ageing on parking performance: a parametric manipulation of salience and relevance of contextual components.

The Master Activation model of attention (Michael, Vairet, and Fernandez, Capture attentionnelle en vision: La saillance, la pertinence, et la balance cortico-sous-corticale. In: G. A.

Low conspicuity of motorcycles for car drivers: dominant role of bottom-up control of visual attention or deficit of top-down control?

Objective: The aim of this study was to evaluate whether the low visibility of motorcycles is the result of their low cognitive conspicuity and/or their low sensory conspicuity for car drivers.

Background: In several cases of collision between a car and a motorcycle, the car driver failed to detect the motorcyclist in time to avoid the collision.

Method: To test the low cognitive conspicuity hypothesis, 42 car drivers (32.

Deterioration of the useful visual field with age and sleep deprivation: insight from signal detection theory.

The goal of this study was to establish whether the deterioration of the useful visual field due to sleep deprivation and age in a screen monitoring activity could be explained by a decrease in perceptual sensitivity and/or a modification of the participant's decision criterion (two indices derived from signal detection theory). In the first experiment, a comparison of three age groups (young, middle-aged, elderly) showed that perceptual sensitivity decreased with age and that the decision criterion became more conservative. In the second experiment, measurement of the useful visual field was carried out on participants who had been deprived of sleep the previous night or had a complete night of sleep.

Behavioural reactivation and subjective assessment of the state of vigilance--application to simulated car driving.

The frequency of some behaviour (such as self-centred gestures) increases during a task that leads to the occurrence of low-vigilance episodes. These gestures can be useful in stimulating oneself. A study carried out in 20 adults has enabled us to state that motor activity (recorded with an actimeter) increases with the duration of a monotonous driving task and sleep deprivation.

Sleepiness in professional drivers: effect of age and time of day.

The effect of age and time of day on objective and subjective sleepiness in professional drivers was investigated during a simulated driving task. Thirty-six young and middle-aged professional males drivers, free from any sleep disorder, took part in two simulated driving sessions; one carried out in the afternoon (between 2 and 4 p.m.

Effect of driving duration and partial sleep deprivation on subsequent alertness and performance of car drivers.

The effect of partial sleep deprivation and driving duration on subsequent alertness and performance in car drivers was investigated. Twenty healthy male subjects, between 25 and 55 years of age, free from any sleep disorder, took part in two simulated driving sessions carried out between 2 p.m.

Useful visual field reduction as a function of age and risk of accident in simulated car driving.

Purpose: To study the relationships between the reduction of the useful visual field, age, and driving performance.

Methods: Forty-eight subjects, aged from 23 to 77 years performed a test to evaluate the size of their useful visual fields. The test involved the detection and localization of peripheral signals that could appear in an area of 70 degrees of visual angle.

Influence of age, speed and duration of monotonous driving task in traffic on the driver's useful visual field.

Recent research has shown that the useful visual field deteriorates in simulated car driving when the latter can induce a decrease in the level of activation. The first aim of this study was to verify if the same phenomenon occurs when driving is performed in a simulated road traffic situation. The second aim was to discover if this field also deteriorates as a function of the driver's age and of the vehicle's speed.

A critical review of techniques aiming at enhancing and sustaining worker's alertness during the night shift.

Two types of methods based on a particular principle allow enhancing and sustaining workers' alertness all along their night work. The first one rather consists in arousing workers by exposing them to stimulant environment conditions (light or noise..

Analysis of the deformation of the useful visual field: a comment on Rantanen (2003).

In the study of variables which may affect peripheral visual perception are several ways of assessing deterioration of this perception. One is evaluation of deformation of the useful visual field. Two techniques of analysis have been considered, by calculation of deformation indices, as proposed by Rantanen in 2003 and by carrying out an elliptical interpolation from the location within the visual field of signals perceived by a subject.

Effect of sleep deprivation and driving duration on the useful visual field in younger and older subjects during simulator driving.

Nine older subjects (40-51 years) and 10 younger subjects (18-30 years) took part in two one-hour driving sessions. They performed a very monotonous task during which they had to follow a vehicle either after a complete night of sleep or after one night of sleep deprivation. While driving their useful visual field was assessed by introducing signals that would appear on the whole road scene.

Deformation of the useful visual field with state of vigilance, task priority, and central task complexity.

In a dual-task situation, peripheral perception can deteriorate due to different variables related to the experimental situation, such as central task complexity and the relative priority given to the two tasks. Recent studies have also shown that individual characteristics (such as the state of vigilance) can alter the useful visual field. The ability to perceive signals presented at different places in the visual field decreases in situations that lead to episodes of low vigilance.