Using Micro-Doppler Radar to Measure Gait Features Associated With Cognitive Functions in Elderly Adults

Abstract

This paper used micro-Doppler radar (MDR) measurements to investigate the significance of associations between cognitive functions and gait features of elderly persons. The aim of this paper was to develop a system that would enable the risks of developing dementia and related diseases to be monitored remotely on a daily basis. Study participants were adults aged 75 years and older. Gait velocity parameters corresponding to the walking speed and leg and foot velocities were remotely extracted via a simple 24-GHz MDR system in real time. The relationships between the extracted gait velocity parameters and the global cognition and cognitive functions in various cognitive domains (processing speed, memory, executive function, and language domains) that were assessed by conventional paper-and question-based tests were statistically analyzed. Our results revealed that, apart from the walking speed, which was mainly considered in a previous study, other parameters reflecting the leg and foot velocities are effective for the detection and classification of elderly participants with lower cognitive functions in the various cognitive domains. In particular, the statistical significance of the association of the leg velocity in the swing phase with the results of all the cognitive function tests is larger than that of the walking speed. Another important finding is that different gait velocity parameters are associated with each cognitive domain and this means that the MDR-based gait measurement can be used to determine which cognitive domain has deteriorated.

Screening of mild cognitive impairment in elderly via Doppler radar gait measurement

“…The reason for MCI screening capability using the extracted gait parameters is that the gait dysfunction due to cognitive decline was detectable even though the decline is mild. In our previous study [6], the participants with larger cognitive declines in various cognitive domains were classified with the radar gait parameters. Although the MCI corresponds to a milder cognitive decline compared to our previous study, Ref.…”

“…Thus, the MCI screening was achieved using the gait parameters. However, the parameters extracted from V u ðtÞ were not selected for the logistic regression model despite our previous findings [6] of the efficacy of these parameters in leg forward motion for the evaluation of various cognitive functions. The mechanism of our results including the reason for the ineffectiveness of V u ðtÞ could be investigated using a larger dataset in future studies.…”

“…For a received signal processing to acquire the gait parameters, the similar procedure indicated in Ref. [6] was conducted to extract the time-velocity distribution, and its feature envelopes are shown in Fig. 1.…”

“…Doppler radar technique is a promising candidate for avoiding the above problems because it can measure various gait parameters remotely without constraints of participants and this letter presents a MCI screening via gait sensing using a Doppler radar. Our previous study [6] revealed that the cognitive impairment can be identified via micro-Doppler radar gait measurement. Although this previous study assumed the detection of relatively serious cognitive impairment, we hypothesize that our technique can also be applicable for the screening of the milder decline observed in MCI.…”

Risk of Falling in a Timed Up and Go Test Using an UWB Radar and an Instrumented Insole

“…Recent researches are then focused on advancements and developments of UWB systems for their advantages and feasibility for monitoring gait and fall parameters. The authors in [ 32 ] suggested a relation between cognitive functions in the elderly and the gait velocity measured by a micro-Doppler radar. The use of an UWB technology to detect falls in domestic environments is presented in [ 33 ].…”