ABOVE: © ISTOCK, VITTORIACHE
In the days before a newborn mouse opens its peepers, nerve impulses that have been sweeping randomly across the retina since birth start flowing consistently in one direction, according to a paper published in Science today (July 22). This specific pattern has a critical purpose, the authors say, helping to establish the brain circuitry to be used later in motion detection.
“I love this paper. It blew my mind,” says David Berson, who studies the visual system at Brown University and was not involved in the research. “What it implies is that evolution has built a visual system that can simulate the patterns of activity that it will see later when it’s fully mature and the eyes are open, and that [the simulated pattern] in turn shapes the development of the nervous system in a way that makes it better adapted to seeing those patterns. . ...
