Figure 1. Alterations of fractal correlations in motor activity fluctuations in dementia patients.

(A) 72-hour activity recording of a representative dementia patient. (B) Detrended fluctuation function F(n) of the activity signal shown in (a). F(n) displayed different power-law behavior with different scaling exponent, α₁ and α₂, at time scales smaller than and larger than ~ 2 hours (indicated by dotted dashed line). For comparison, F(n) of young adults as observed in a previous study¹³ was also plotted (dashed black line). (C) Difference between α₁ and α₂ for all subjects (except for 5 individuals with no α₂ due to many missing data points in their recordings). The subject # 13 (filled circle) is the patient whose data are shown in (A) and (B).