Central Auditory Processing Disorder (CAPD) affects up to 3 percent of children. CAPD generally refers to a variety of disorders that affect the way the brain processes auditory information. Children diagnosed with CAPD typically suffer speech and language disorders as well as learning disabilities. While the cause of CAPD is generally unknown, recent research on how the brain learns to hear may shed some insight into this issue.
For years, auditory researchers have speculated that electrical impulses transmitted from the inner ear actually help teach the brain how to hear. Researchers at the Pitt School of Medicine recently published some insightful research and in the online journal Neuron; this research sheds new light on our understanding of how we learn to hear.
In their research, neural connectivity was mapped on mice. The ear produces rhythmic bursts of electrical activity prior to the ability to hear has developed. Over time, the brain organizes these bursts, cultivating the ability to remove unneeded connections while strengthening more necessary links. Researchers then removed a key neural receptor, leading to a failure of the mice to develop properly. The result was that these mice could detect sound, but would have trouble perceiving the pitch of sounds.
This difficulty in discerning pitch is akin to the subtle hearing deficits associated with CAPD. Dr. Karl Kandler of the Pitt School of Medicine research team sums up the importance of this recent research, stating, "Our findings suggest that an abnormal rhythm of electrical impulses early in life may be an important contributing factor in the development of CAPD. More research is needed to find out whether this also holds true for humans, but our results point to a new direction that is worth following up.”
Source: Science Daily