A Week in the Dark Rewires Brain Cell Networks and Changes Hearing in Adult Mice
Scientists have known that depriving adult mice of vision can increase the sensitivity of individual neurons(神经元) in the part of the brain devoted to hearing. New research from biologists at the University of Maryland revealed that sight deprivation also changes the way brain cells interact with one another, shifting the mice's sensitivity to different frequencies.
"This study reinforces what we are learning about how manipulating vision can have a significant effect on the ability of an animal to hear long after the window for auditory(听觉的) learning was thought to have closed," said Patrick Kanold, senior author of the study.
It was once thought that the sensory regions of the brain were not adaptable after a critical period in childhood. This is why children learn languages much more readily than adults. Kanold's earlier research disproved this idea by showing that depriving adult mice of vision for a short period increased the sensitivity of individual neurons in the auditory cortex(皮质), which is devoted to hearing.
Young brains wire themselves according to the sounds they hear frequently, assigning areas of the auditory cortex to specific frequencies based on what they are used to hearing. The researchers found that, in adult mice, a week in the dark also changed the distribution of space to different frequencies.
"We don't know why we are seeing these patterns," Kanold said. "We speculate that it may have to do with what the mice are paying attention to while they are in the dark."