Enhanced Screening for Preclinical Cognitive Vulnerability Using Target-Specific Dwelling Time in the Digital Trail Making Test Part A—A Pilot Study

BACKGROUND: Community-based cognitive screening requires efficient, low-burden tools. We examined "dwelling time" (time spent by the pen-tip on a specific target) during the digital Trail Making Test (TMT)-A as a potential marker for early cognitive changes. METHOD: In this cross-sectional study, we included 91 community-dwelling older adults (mean age 74.4 y) classified into low Memory Performance Index (MPI) (preclinical decline, score <50.2, n=35) and normal groups (n=56). Using a tablet and stylus, dwelling times during digital TMT-A were analyzed, focusing on 5 high-interference targets most strongly associated with MPI. RESULTS: The low MPI group had significantly longer dwelling times at the identified targets. In regression models, the sum of these dwelling times independently predicted MPI (β=-0.200, P=0.020), whereas conventional total completion time did not (β=-0.132, P=0.157). Adding this dwelling time metric to a demographic-based model improved the area under the curve (AUC) from 0.818 to 0.845. CONCLUSIONS: For preclinical stages, dwelling time at specific targets is a more sensitive marker of cognitive decline than total completion time. This digital pen-tip behavioral analysis provides a quick, accurate, and low-stress screening tool for preclinical cognitive vulnerability in primary care.