Functional near infrared spectroscopy data acquisition and preprocess
PD, gait impairments
CORTEX
A 35‐channel portable fNIRS device (Nirsmart, Huichuang) was utilized. The sample frequency was 11 Hz, and the wavelengths were 760 and 850 nm. Given that prefrontal and sensorimotor cortex activity was correlated with gait impairments in PD,The experiment conducted in a quiet room with soft light included two phases: (1) participants were instructed to stand quietly, look straight ahead, and think of nothing for 15 s and (2) when hearing the ‘start’ command, participants walked for 65 s at their comfortable pace back and forth over a 5‐m distance, with a 180‐degree turn at each end. Notably, participants were required to stand still for at least 1 min to ensure stable blood pressure before each experiment. An internal software named NirSpark (Huichuang) was used to preprocess the fNIRS data. The steps are as follows