Postural Control and Somatosensory Information: Effects of Aging and Parkinson’s Disease

Sensory information from visual, vestibular, and somatosensory systems plays an important role in postural control. Deficits in postural control performance are the primary cause of the increased number of falls during aging. Postural instability in older adults is related to a decline in sensory and motor function and this can be more evident when associated with Parkinson’s disease (PD). Among the declines in the sensory systems, deficits in the somatosensory function have been identified in older adults and these appear to be even higher in people with PD. Evidence supporting the importance of the somatosensory system in postural control comes from experiments that artificially reduced sensitivity in the soles of the feet and studies involving individuals with compromised plantar sensation. In an attempt to improve somatosensory input, previous research has shown that artificially enhancing cutaneous information can improve postural control. This chapter aims to describe the postural control of neurologically healthy older adults and people with PD and highlight the importance of somatosensory information to postural control in both populations. In addition, we will discuss some therapies using enhanced somatosensory information to improve postural control and, consequently, prevent or reduce falls.