Event-related perturbation in spectral power and in potentials during periodic fast and slow motor imagination for brain-controlled robots interface

The study explored event-related perturbation in spectral power and in potentials during periodic fast and slow motor imagination of left and right index finger and right toe based on EEG. EEG signals were collected from 4 healthy volunteers during imagination of six tasks that involved three limbs (left and right index fingers and right toes ) and two speeds (fast and slow) and each task repeated 40 times in random order. In a single trial, periodic fast or slow motor imagination was executed. EOG and EMG signals are eliminated by independent component analysis (ICA). Time/frequency analysis is applied to characterize mean event-related changes in the power spectrum during single trials across subjects. Grand average event-related potentials (ERPs) is filtered 2Hz cut-off frequency by IIR filter to extract slow potentials and compared between fast and slow. The distinctive frequency bands and time ranges for significant changes in power related to motor imagination at different speeds and different limbs are found in the paper. Periodic slow motor imagination may invoke more positive slow potentials than fast motor imagination and fast movement imagination reaches at maximum positive peak more quickly than slow movement imagination. Executing periodic fast and slow motor imagination of left and right index fingers and right toes during a single trial is a new mental control strategy paradigm for human-machine interface. The result of experiment research may be very important. The study may provide some alternative feature patterns for Brain-controlled robots (BCR) based on fast and slow motor imagination.