Recent research showed that fitting deaf children with implants immediately after birth improves their brain activity.

Research team led by Rob Shephard of the Bionic Ear Institute in Melbourne studied how this artificial stimulation affects the brain using animal models.

Researchers recorded electrical activity in the cortex of 17 8-month-old cats that were deaf from birth. Each cat's cochlear implant was activated while researchers monitored their brains.

Research team said that 10 of the cats had received the implant relatively recently, and their electrical activity was "completely scrambled", indicating that they did not perceive sound coherently: normal cortex activity is key to perceiving sound and, in humans, to developing speech. However, in the seven cats that received implants at 8 weeks old, brain activity was similar to that in hearing cats.

Neurologist Jim Pickles of the University of Queensland says the latest work "increases the weight of evidence to implant children early".