Rats with hearing deficits can be trained to overcome their sound identification problems, something researchers previously only speculated was possible. The animals, raised to struggle to distinguish one sound from another, display improved neuronal fidelity, according to research in Nature Neuroscience this week.
Temporal processing is important for distinguishing speech from background noise. It has been suggested that deficits in temporal processing in young children can lead to delayed and impaired language development, as well as problems in reading.
Previous studies have shown that it is possible to improve neuronal responses which affect temporal processing with training, but these were all carried out in unimpaired adults. Xiaoming Zhou and Michael Merzenich look at whether this training could alter the neural responses in developmentally impaired rats. They found that in animals that had reduced cortical responses initially, due to being raised in an abnormal environment, training improved the ability to distinguish a target noise from many different background noises. This was accompanied by an improvement in the temporal fidelity of cortical neuron responses that was maintained for at least 2 months after the training ended.
In humans, it has been suggested that intensive training to improve temporal processing in children is successful as it helps them code auditory information better. This study suggests that behavioral training affects auditory responses in an area normally involved in temporal processing.