Vision: Rods See in Bright Light

Bilateral loss of vision in bright light.

We describe four patients with episodic bilateral vision impairment related exclusively to light exposure. Each had angiographically documented bilateral high-grade stenosis or occlusion of the internal carotid arteries. This phenomenon appears to be related to bilateral simultaneous retinal ischemia delaying regeneration of visual pigments in the pigment epithelial layer. It must be distinguis...

Polarisation Vision: Beetles See Circularly Polarised Light

It has long been known that the iridescent cuticle of many scarab beetles reflects circularly polarised light. It now turns out that scarabs can also see this light, potentially using it as a covert visual signal.

Bright Storage of Light

Mammalian Vision: Rods Are a Bargain

To maintain resting potentials in darkness, rod and cone photoreceptors incur a significant energy cost. But in brighter light, rods become energetically 'cheaper' than cones, which might explain the evolution of the vertebrate duplex retina.

The effect of Bright light on Fatigue and sleepiness in night shift work nurses

Objective: In this study we assessed the effect of bright light emitted by light box on fatigue, and sleepiness in nurses. Methods: 44 healthy female shift work nurses were allocated into two groups of intervention and control. In the first stage, bright light was emitted to the nurses in the intervention group by the light box, and bright light was not emitted to the control group. In the nex...