A population-based, longitudinal investigation of changes in multisensory integration with ageing and its causal role in the incidence of falls and cognitive decline in older adults

 

Our sensory systems are constantly bombarded by information, yet we are able to maintain a coherent perception that allows us to efficiently interact with our world. Recent research in neuroscience has led to important breakthroughs in our understanding of how multisensory interactions occur in the brain. However, the ageing process can affect the manner by which multisensory information is combined. That is, as we get older, the brain's ability to combine relevant sensory inputs, whilst ignoring task-irrelevant inputs, becomes less efficient and this can have an effect on higher-level cognitive, social and some physical functions. We have adapted a simple pereptual task, called the 'sound-induced flash illusion' to measure this multisensory process in older adults. Level of susceptibility to this illusion suggests the efficiency with which sensory inputs are combined in the brain (i.e. high susceptibility suggests inefficient sensory integration). We found that older adults with a history of falls are more susceptible to this illusion than healthy adults. Given that the maintenance of postural control and balance are tasks which are essentially multisensory, these findings suggested that there may be a causal link between inefficient multisensory integration and the incidence of falls. The main aim of the proposed research, therefore, is to provide evidence for such a causal link. We plan to do this via the TILDA study by measuring performance to this illusion in a large sample of older adults and comparing changes in performance with other measures of physical and cognitive function. Our study will provide novel insights into how the older brain encodes and processes multisensory information from the environment, and the extent to which inefficient integration may lead to a fall or cognitive decline. Our findings will therefore help elucidate how efficient multisensory integration underpins healthy physical, social and cognitive performance in older age.

Award Date
30 June 2017
Award Value
€368,898
Principal Investigator
Professor Fiona Newell
Host Institution
Trinity College Dublin
Scheme
Investigator Led Projects