This is a Discovery Research Grant awarded to Dr Fabiola Paciello at the Universitá Cattolica del Sacro Cuore, Italy, in 2024. We are co-funding this project in partnership with Alzheimer’s Research UK.
Background
Evidence suggests that people with mild hearing loss (developing in later life) are nearly twice as likely to develop Alzheimer’s disease (AD), the most common form of dementia, as those with normal hearing. This risk increases with the severity of hearing loss, with severe hearing loss increasing the risk of developing dementia by five times.
Despite this, we still don’t fully understand the connection between hearing loss and dementia. Researchers around the world have been investigating this link, but we still have limited information about why people with hearing loss are more susceptible to developing dementia.
Aim
The aim of this project is to understand whether hearing loss and dementia share disease causing mechanisms and how hearing loss impacts on and changes cognitive activity in the brain.
To learn more about the link between hearing and cognition, the researchers will study a mouse model of Alzheimer’s disease (called 3×Tg-AD mice) and compare them to healthy mice as the two groups of mice age. The 3×Tg-AD mice develop many of the same symptoms and features of Alzheimer’s disease as people with the condition.
The researchers will analyse the inner ear and brains of these mice, at the functional (how they work), morphological (overall structure) and molecular (cellular) levels, to identify damage to the auditory system that is caused by the presence of Alzheimer’s disease (if any) and/or by advancing age. They will also assess changes in the brain that are involved in hearing and cognition in these mice to see if there is a link between hearing loss and dementia susceptibility. Finally, they will investigate how brain structures involved in hearing and cognition can talk to and influence each other.
Benefit
The results of this project will identify molecular processes that are shared between hearing loss and dementia and show how hearing (or hearing loss) can impact cognitive functions by studying connections in the brain between auditory and cognitive brain areas. The project may also provide insight into how hearing loss prevention and treatment can lessen the impact of age related brain diseases such as dementia.
The results from this project will shed light on the cause-effect relationship between hearing loss and cognitive decline and help to identify potential treatments for both conditions.