Bright lights, not-so-big pupils

piggy submitted, created time 5 days 2 hours (www.eurekalert.org)

A team of Johns Hopkins neuroscientists has worked out how some newly discovered light sensors in the eye detect light and communicate with the brain. The report appears online this week in Nature.

These light sensors are a small number of nerve cells in the retina that contain melanopsin molecules. Unlike conventional light-sensing cells in the retina—rods and cones—melanopsin-containing cells are not used for seeing images; instead, they monitor light levels to adjust the body's clock and control constriction of the pupils in the eye, among other functions

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Algal protein causes blind mice to react to light

Darkfrog submitted, created time 8 months 1 week (www.nature.com)

Blind mice have been made to react to light in the lab. Scientists have used a protein found in algae to make little systems that react to light. When properly attached, these proteins can switch neurons on and off almost like natural photoreceptors do. It's not too clear how well the mice can actually see, but they can now tell the difference between "lights on" and "lights off." The scientists suppose, too, that the mice can only see in black and white

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Fly Photoreceptors Demonstrate Energy-Information Trade-Offs in Neural Coding

dovechocolate submitted, created time 1 year 9 months (biology.plosjournals.org)

Many animals show striking reductions or enlargements of sense organs or brain regions according to their lifestyle and habitat. For example, cave dwelling or subterranean animals often have reduced eyes and brain regions involved in visual processing. These differences suggest that although there are benefits to possessing a particular sense organ or brain region, there are also significant costs that shape the evolution of the nervous system, but little is known about this trade-off, particularly at the level of single neurons

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