Investigation of Dose-Response Relationships for Effects of White Light Exposure on Correlates of Alertness and Executive Control during Regular Daytime Working Hours.

To date, it is largely unknown which light settings define the optimum to steer alertness and cognitive control during regular daytime working hours. In the current article, we used a multimeasure approach combined with a relatively large sample size ( N = 60) and a large range of intensity levels (20-2000 lux at eye level) to investigate the dose-dependent relationship between light and correlates of alertness and executive control during regular working hours in the morning and afternoon. Each participant was exposed to a single-intensity light level for 1 h after a 30-min baseline phase (100 lux at the eye) in the morning and afternoon (on separate days) during their daily routine.

The effect of spatial luminance distribution on dark adaptation.

Recent studies show that dark adaptation in the visual system depends on local luminance levels surrounding the viewing direction. These studies, however, do not explain to what extent veiling luminance is responsible for the outcome. To address the latter, in this study dark adaptation was measured for three different spatial luminance distributions surrounding a target to be detected, while keeping the veiling luminance at the location of the target equivalent.

Detection of temporal delays in visual-haptic interfaces.

This paper addresses the question of how large the temporal delay between a visual and a haptic stimulus may be such that the stimuli are still perceived as being synchronous. Participants had to judge whether the moment at which a graphical object collided with a virtual wall occurred simultaneously with the moment at which a force was felt through a force feedback joystick. Participants either moved the joystick to drive the object (active touch) or held the joystick in a steady position while the object moved by itself (passive touch).