Abstract: Pain, as a common symptom, seriously affects the patient’s health. The aim of this work was to study the physiologicalresponses of the brain and identify the features of Electroencephalography (EEG) signals related to friction pain. Theresults showed that the primary brain activation evoked by friction pain was located in the Prefrontal Cortex (PFC). Theactivation area decreased, and the negative activation intensity in the PFC region increased with increasing intensity ofpain. The inhibitory interactions between different brain regions, especially between the PFC and primary somatosensorycortex (SI) regions were enhanced, and excitatory-inhibitory connections between the medial and lateral pain pathwayswere balanced during pain perception. The percentage power spectral density of the α rhythm (Dα), dominant singularitystrength (αpeak) and longest vertical line (Vmax) of EEG signals induced by pain significantly decreased, and the percentage power spectral density of the β rhythm (Dβ) significantly increased. The combination of multiple features of Dα, Dβ,αpeak and Vmax could significantly improve the average recognition accuracy of different pain states. This study elucidatedthe neural processing mechanisms of friction-induced pain, and EEG features associated with friction pain were extractedand recognized. It was helpful to study the brain feedback mechanisms of pain and control signals of Brain-ComputerInterface (BCI) system related to pain.

Key words: Friction pain, Brain activation, EEG feature recognition, BCI')">Friction pain, Brain activation, EEG feature recognition, BCI