Researchers have uncovered a way to identify individuals who may be at a higher risk for dementia by analyzing mobility data collected during a smartphone-based navigation task on a university campus. The results, published in the journal PLOS Digital Health, demonstrate the promise of using smartphone data captured in realistic settings for the early detection and ongoing monitoring of Alzheimer’s disease. The study involved 72 adults, roughly one-third of whom were experiencing subjective cognitive decline (SCD), a condition recognized as a risk factor for dementia.
A team from DZNE and Otto von Guericke University Magdeburg has managed to identify individuals at heightened risk for dementia by studying mobility data gathered while participants engaged in a smartphone navigation task on campus. The findings, published in PLOS Digital Health, highlight how smartphone data collected in everyday contexts can aid in the early diagnosis and tracking of Alzheimer’s disease. The study included 72 adults, approximately a third of whom experienced subjective cognitive decline (SCD), a known risk factor for dementia.
Alzheimer’s disease often progresses silently over many years and ultimately leads to dementia, for which there is currently no remedy. “Alzheimer’s is frequently treated too late for effective therapy,” explains Dr. Anne Maass, a research group leader at DZNE and guest professor at University Magdeburg. “Even the latest antibody treatments being discussed are only effective if administered early. Hence, early diagnosis is crucial when symptoms are still subtle. We need advancements in diagnostics,” she adds. Along with her colleagues, she explored a new method for evaluating spatial navigation issues, which may be one of the first observable symptoms of Alzheimer’s disease.
App in Action
“Our research was conducted as a scavenger hunt where participants were tasked with locating specific points of interest using a smartphone app we created,” shares Dr. Nadine Diersch. The neuroscientist, who initiated the project years ago at DZNE and now works in the private sector while still collaborating with DZNE as a guest researcher, mentions that “Certain app data can reliably indicate individuals at an increased risk for dementia.” This research indicates that digital technologies, such as mobile applications, can provide new approaches to evaluate cognitive function in low-pressure, realistic settings. In the future, this might facilitate the recognition of early cognitive shifts and potential precursors to dementia.
Campus Scavenger Hunt
A total of 72 individuals, aged between their mid-twenties and mid-sixties, participated in the study. Among the 48 older participants, 23 were classified as SCD patients. Those suffering from SCD sense a decline in cognitive ability, although traditional neuropsychological tests may not detect this. While SCD does not guarantee the onset of dementia, it does correlate with a higher risk. All participants were instructed to navigate independently to various buildings on the University Magdeburg medical campus, guided by the app, which monitored their movements via GPS. “All our participants had a similar familiarity with the campus and were proficient smartphone users. We also had a practice session with the app beforehand,” said Jonas Marquardt, the study’s lead author and PhD student in Anne Maass’s research group.
Evaluating Navigation Skills
Each participant had to visit five buildings along an approximately 800-meter route, guided by the app, which acted as a pacekeeper by showing their current location and destination on a map. The map would disappear as soon as the participant started walking. “Participants needed to memorize street layouts, their location, and destination, using their navigational instincts and spatial memory,” shared Marquardt. “If they lost their way, they could press a help button in the app, which would briefly show the map, position, and destination again.” The researchers utilized GPS data to create individual mobility profiles and extract additional insights.
Notable Pauses
In most instances, participants reached all five destinations in under thirty minutes. “Generally, younger participants performed better, covering shorter distances on average and relying less on the help feature compared to older participants,” Marquardt noted. The principal differences between older adults with and without SCD were observed in the number of “orientation stops” made during the task. “Older adults with SCD tended to pause more frequently while walking, likely to reorient themselves, compared to older adults without SCD. This parameter allowed us to identify individuals with SCD,” explains Marquardt.
Implications for Early Detection
The reasons behind SCD participants’ distinct behavior remain uncertain. “We observed that they particularly hesitated longer at intersections, indicating potential changes in decision-making processes. However, the data isn’t conclusive yet,” noted Nadine Diersch. “Still, our study’s findings provide a promising proof of concept, indicating that smartphone data can assist in detecting subtle cognitive declines in realistic environments.” The scientist sees a future where such apps could be used for early detection and treatment of dementia: “I can envision these applications identifying at-risk individuals and determining whether further assessments or treatment are necessary.”
Funding: This research was supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through the Collaborative Research Centre “Neural Resources for Cognition” and a DZNE Innovation-2-Application Award.
