Stimulating the brains of deaf rats, that have hearing implants, can further improve their recognition of sounds.
A study by the New York University School of Medicine, USA, showed that the rats rapidly recognised tunes - that they had been trained to respond to before being made deaf for the study - and that this was linked to an increase in activity in a region of the brain called the locus coeruleus (LC), which is involved in learning, cognition and attention.
When the researchers stimulated the LC they saw that the rats could recognise tunes after three days, compared to nine days for rats that did not have the brain stimulation.
Cochlear implants are used to help people with little to no hearing by converting sounds into electrical signals that can be processed by the brain. However, this process can sometimes take years.
Dr Erin Glennon at NYU said: “Our findings suggest that differences in neuroplasticity, particularly in parts of the brain such as the locus coeruleus, may help explain why some cochlear implant users improve faster than others.”