Contactless Gait Assessment in Home-like Environments.

Gait analysis is an important part of assessments for a variety of health conditions, specifically neurodegenerative diseases. Currently, most methods for gait assessment are based on manual scoring of certain tasks or restrictive technologies. We present an unobtrusive sensor system based on light detection and ranging sensor technology for use in home-like environments. In our evaluation, we compared six different gait parameters, based on recordings from 25 different people performing eight different walks each, resulting in 200 unique measurements. We compared the proposed sensor system against two state-of-the art technologies, a pressure mat and a set of inertial measurement unit sensors. In addition to test usability and long-term measurement, multi-hour recordings were conducted. Our evaluation showed very high correlation (r>0.95) with the gold standards across all assessed gait parameters except for cycle time (r=0.91). Similarly, the coefficient of determination was high (R2>0.9) for all gait parameters except cycle time. The highest correlation was achieved for stride length and velocity (r≥0.98,R2≥0.95). Furthermore, the multi-hour recordings did not show the systematic drift of measurements over time. Overall, the unobtrusive gait measurement system allows for contactless, highly accurate long- and short-term assessments of gait in home-like environments.

Development and evaluation of a new virtual reality-based audio-tactile cueing-system to guide visuo-spatial attention.

Spatial attention is an important feature for filtering everyday inputs. The direction of the attention can be guided by the use of visual, auditory or tactile stimuli. The literature regarding the effect of cueing spatial attention in visual search tasks consistently shows an improvement in accuracy and reaction time. So far, most studies have used two-dimensional setups, for which ecological validity may be questioned. In this study with healthy participants, we investigated the feasibility of a virtual reality-based setup. We examined the feasibility and compared the performance in a visual search task as auditory, tactile or combined cues were given. The results revealed high usability and a significantly higher detection rate for combined audio-tactile cues compared to auditory cues alone.