Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we will assume that you are happy to receive all cookies and you will not see this message again. Click 'Find out more' for information on how to change your cookie settings.

A collaborative King Group study published today in Nature Communications enhances our understanding of how our brains learn to adapt to abnormal sensory changes such as hearing loss. Their results could inform the future development of devices that restore hearing or other sensory impairments.

The brain has a remarkable capacity to adapt to changes in sensory inputs and to learn from experience. However, the neural circuits responsible for this flexible processing remain poorly understood. A new study from the King Group in collaboration with Associate Professor Ed Mann and Associate Professor Ed Boyden from MIT identifies the key part of the brain that drives auditory perceptual learning and enables us to adapt to hearing loss.

In essence, their study shows that the auditory cortex plays a critical role in learning to adapt to the abnormal auditory spatial cues that result from hearing loss in one ear. Training leaves a memory trace, which facilitates adaptation to a second period of hearing loss. However, evidence suggests that after the initial learning, the recovery in sound localisation accuracy is independent of cortical activity. "This type of rapid plasticity is likely to be extremely important when people experience hearing loss or other sensory impairments, and particularly when their hearing is partially restored via a hearing aid or cochlear implant." (Professor Andrew King).

The methodology behind these conclusions is particularly innovative. The team, which includes Associate Professor Victoria Bajo Lorenzana and Dr Fernando Nodal, used optogenetic tools to silence the activity of the auditory cortex. They silenced the auditory cortex in ferrets with a laser green light at the same time as the animals heard a sound. The light activated an proton pump called ArchT in the neural membrane that has been expressed after viral transfection of the ArchT gene. As a consequence, when the light is on, the neurons in the auditory cortex were shown to be hyperpolarized and therefore silenced.

Crucially, the results demonstrate the essential role of primary sensory cortices in perceptual learning, and could inform how hearing aids or cochlear implants are developed in future. Furthermore, according to first author Prof Bajo Lorenzana, the significance of these results does not only relate to hearing loss:

 

The wider significance is not only related to the auditory field, but potentially to other senses such as vision or touch. There are implications for the design and generation of new prosthesis that can change the activity of the cerebral cortex and therefore promote sensory learning. - A/Prof Bajo Lorenzana

The full publication "Silencing cortical activity during sound-localization training impairs auditory perceptual learning" is available to read in Nature Communications.

Similar stories

New research to radically alter our understanding of synaptic development

Publication Research

A new study from the Molnár group on the role of regulated synaptic vesicular release in specialised synapse formation has made it to the cover of Cerebral Cortex.

Being "in the zone": how waking activity controls sleep need

Publication Research Vyazovskiy Group News

A new study from the Vyazovskiy group suggests that how and where we spend our time while awake impacts how much we need to sleep - it does not only depend on how long we are awake.

New target identified to develop treatment for Abdominal Aortic Aneurysm

Cardiac Theme Publication Research

A new study from the Smart group has shed light on a key regulatory step in the initiation and progression of Abdominal Aortic Aneurysm by revealing the protective role of a previously little known small protein.

Researcher publishes children's book of the brain

Postdoctoral Publication

Betina Ip, a Royal Society Dorothy Hodgkin Research Fellow based in NDCN, formerly a postdoctoral research scientist in DPAG, has written a book for children: The Usborne Book of the Brain and How it Works.

Drug trial that could improve respiratory recovery from COVID-19 now underway

Research

A clinical trial has commenced this week to test whether a drug called almitrine can help people who are seriously ill with COVID-19 to recover from the disease.