Zusammenfassung

The daily amount of falls is increasing with increasing age and due to balance influencing impairments. In order to reduce the related number of falls and fall-related deaths, mainly physical training interventions were investigated so far. In this proposed project, we plan to investigate a novel approach to reduce the number of daily falls. Jointly conducted studies of the applicants revealed that contact-free ultrasound, applied at the footsoles while standing, improves balance related measures. Similar effects were observed by other researchers using vibrating actuators, which, however, need to be in direct contact with the human skin.
Compared to those, ultrasound allows a versatile choice of the signal shape, the amplitude, and the frequency. The functional mechanism of the balance improving effect is still unclear. However, it is assumed that vibration improves the sensory perception, the processing or the transfer of sensor signals. The first aim of the proposal is to maximize the balance enhancing effect by optimizing the adjustable parameters. Second, the optimal body locations for the application should be identified to gain a better insight of the involved body systems. Next to local application points such as the foot sole, other body regions with sensors providing position, length, force or velocity information can be preferred regions for the application. In particular, regions that include balance related muscles (calf muscles) and tendonds (Achilles tendon) are worth to be investigated. If the vibration, based on ultrasound, affects global systems that are responsible for signal processing and transfer, one can argue that every region on the body with an increased amount of sensors is a good access point. In a third project phase, the effect found valid for standing people shall be tested to be valid for walking people as well, since most falls occur during gait.