Brief Report| Volume 28, ISSUE 8, P820-825, August 2020

Radio Signal Sensing and Signal Processing to Monitor Behavioral Symptoms in Dementia: A Case Study

Published:March 07, 2020DOI:


      • A noncontact sensor device may help to identify behavioral symptoms of dementia.
      • In this case report, the device transmitted 96.2% of data with no adverse events.
      • Device data, in tandem with caregiver report, revealed an association between changes in patterns of motion and socio environmental triggers.



      Alzheimer's Disease (AD)-related behavioral symptoms (i.e. agitation and/or pacing) develop in nearly 90% of AD patients. In this N = 1 study, we provide proof-of-concept of detecting changes in movement patterns that may reflect underlying behavioral symptoms using a highly novel radio sensor and identifying environmental triggers.


      The Emerald device is a Wi-Fi-like box without on-body sensors, which emits and processes radio-waves to infer patient movement, spatial location and activity. It was installed for 70 days in the room of patient ‘E’, exhibiting agitated behaviors.


      Daily motion episode aggregation revealed motor activity fluctuation throughout the data collection period which was associated with potential socio-environmental triggers. We did not detect any adverse events attributable to the use of the device.


      This N-of-1 study suggests the Emerald device is feasible to use and can potentially yield actionable data regarding behavioral symptom management. No active or potential device risks were encountered.

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