Hearing loss may be a contributing factor to Alzheimer's disease

Aging is something we all have to deal with. And it’s no fun – your body gradually loses some of its capacities and you’re left wondering what you will be able to do tomorrow. One of the parts of aging is losing senses – older people tend to have impaired hearing. Now scientists at Newcastle University began wondering whether hearing impairment and dementia are actually connected.

Scientists believe that hearing loss may be related to dementia to a point where tackling one could prevent the other. Image credit: heptc via Wikimedia (CC BY-SA 4.0)

In fact, scientists believe that hearing loss may cause dementia. They also think that preventing hearing loss may help prevent dementia at least in some cases. Sensory impairment – such as hearing and vision loss – is considered to be a normal part of aging. Stereotypes dictate that old people watch TV on a very high volume, because otherwise they cannot hear anything. However, hearing loss is a terrible thing and we shouldn’t be accepting it as a normal part of life – we have to find ways of preventing it. And now scientists think there might be more motivation to fix the hearing loss problem, associated with aging.

Old people are losing their hearing and cognitive abilities, but what if one is causing the other? Scientists decided to check that out. They wanted to see if hearing loss and cognitive decline are simply caused by the same factors (aging). Or if the loss of audible sensory stimulation accelerates shrinking of the brain. Or maybe the brain just has to dedicate more of its resources towards compensating the effects of hearing loss. Professor Tim Griffiths, one of the authors of the study, said: “The challenge has been to explain how a disorder of the ear can lead to a degenerative problem in the brain. We suggest a new theory based on how we use what is generally considered to be the memory system in the brain when we have difficulty listening in real-world environments”.

Hearing loss is not necessarily an ear issue. Sounds that find their way into your ears are later interpreted by your brain as information. Scientists believe that the temporal lobe, brain area associated with long-term memory for places and events, may be involved in manipulation of auditory information. Scientists believe that hearing loss may trigger changes in the temporal lobe. But they also think that Alzheimer’s disease and hearing loss may just trigger each other. The good news is that if we learned to protect older people’s hearing, we may actually prevent dementia.

So far this study is more of a theoretical work. We don’t know – maybe both cognitive decline and hearing loss are caused by the same factors that are uncontrollable. Or maybe Alzheimer’s disease affects the brain so much people start losing senses. We do know, however, that this area is worth researching, because it might open the doors towards a more effective treatment for dementia.


Source: Newcastle University