A team of scientists from the Institute of Neurosciences at the University of Oregon (USA) has identified the region of the brain that is responsible for processing silences in spoken language. As Michael Wehr and his colleagues explain in Neuron magazine, there are separate channels for processing the presence and absence of sound . The two channels converge in an area of the brain called the auditory cortex , located in the temporal lobe.
By studying the activity of neurons in this brain region in rats, and testing their response to different wavelengths and sound frequencies, the scientists found that a set of synapses (connections between neurons) responded strongly to the onset of sounds, but a different group of synapses responded to the sudden disappearance of sounds. Being able to detect when sound is interrupted , the researchers conclude, is essential for processing spoken language , because it allows us to identify the boundaries between words, even if we are having a conversation in a noisy room.
The findings, Wehr concludes, could be useful for working with children with learning and spoken language deficits, as well as for the design of cochlear implants to combat deafness.
