Researchers from University College Dublin (UCD) and the ULB Neuroscience Institute have shed light on the brain mechanisms underlying age-related changes in postural control.

Aging is known to degrade sensory systems, posing a major challenge to balance control and resulting in an increased risk of falls. Despite its importance, though, the role of the brain has only been explored indirectly, for example, by asking people to perform mental tasks while walking or standing.

Using a novel approach, the researchers discovered that older brains must work significantly harder than younger ones to process sensory information and control movement, alongside a substantial ‘processing delay’.

The research, published in the journal PNAS (Proceedings of the National Academy of Sciences), was led by Dr Thomas Legrand from UCD School of Electrical and Electronic Engineering, alongside an international team of neuroscientists led by Scott Mongold, Mathieu Bourguignon, and Marc Vander Ghinst.

Working with approx. 60 young adults under the age of 30 and 60 people over the age of 65, the research team recorded the brain activity of each participant while they stood on a solid, uniform surface or on a foam block, alternately with their eyes open or closed. Participants also underwent a thorough assessment of their vestibular system – the sensory network in your inner ear that controls balance, spatial orientation, and eye movement.

The study demonstrated that when older adults try to stay balanced, their brain activity syncs up closely with how much they wobble, especially in difficult balancing situations – and those who wobble the most have the highest brain activity.

Dr Legrand said: “This means that older adults have to actively maintain their balance, using parts of their brain to stay upright. Younger people, on the other hand, stay balanced automatically without having to think about it or use up mental energy.

“Furthermore, it takes significantly longer for an older person's brain to process balance information, almost 50 per cent longer. Interestingly, even though many older participants showed inner-ear decline, this wasn't the reason their brains were working so much harder.

“Ultimately, this research helps us understand how the aging brain controls balance, and it opens the door for future studies in medicine and neuroscience to help predict and hopefully prevent fall risks in older adults.”