Keeping Newcastle balanced: balance research in vestibular neuroscience
How do we understand the world around us? A seemingly simple question.
Many would say that we use our five primary senses – vision, hearing, touch, taste, and smell. But sensory neurobiologists would add pain, proprioception and equilibrium to the list. These lesser-known senses are just as important to our everyday function as vision or hearing, but receive far less recognition.
Equilibrium (balance) is responsible for maintaining our stable posture and vision as we move about. Balance is an ongoing, subconscious, and completely vital act (especially if you enjoy being able to stay upright). However, the importance of balance is rarely appreciated until it fails.
"Eat ten hot dogs. Then go on a terrible, spinning carnival ride – the 'tilt-a-whirl'. You get off the ride, but you have this sick, horrible, nasty feeling, and the world just won't quit moving!". This is how a sufferer of Menière's disease (a chronic balance disorder) best describes her symptoms to us (YouTube).
Indeed, balance problems can seriously affect mobility, independence and quality of life, and are a major cause of secondary injury. In our community, complaints of dizziness account for one out of every three visits to the neurologist. Dizziness can be caused by a number of things, but often is due to a problem with the peripheral or central vestibular (balance) system. Unfortunately, effective treatments for dizziness and vertigo are severely limited by a rudimentary understanding of the vestibular system.
HMRI researchers Alan Brichta and Rebecca Lim specialise in vestibular neurobiology. They run a laboratory that studies the finely controlled mechanisms that underlie balance in both the inner ear and the brain. The inner ear houses thousands of sensitive hair cells that can detect head movements and gravity. The brain then uses information from hair cells to switch on the reflexes that control our posture, vision and movements.
In the laboratory, a combination of functional, anatomical, and molecular techniques is used to study this complex sensory pathway. As it is highly specialised, only a handful of scientists in Australia work within the vestibular field. Current research is focused on increasing our understanding of normal vestibular function, so that better clinical treatments can be identified and developed for those who are burdened by balance disorders.
By Lauren Poppi
PhD Candidate, PRC for Translational Neuroscience and Mental Health, The University of Newcastle