Brain-computer interaction method and system for body movement imagination

Abstract

The invention discloses a brain-computer interaction method for imagining body movements, which generates an imaginary task, collects the brain electroencephalogram signal of a subject during the whole process of performing the imaginative task, calculates the characteristics of the motor preparatory potential in the motor-related cortical potential, and calculates the motor-related cortical potential. The joint features of motion potential, motion monitoring potential and event-related synchronization / desynchronization phenomenon in the potential, multi-feature fusion and classification identification are performed on the joint feature, and the classification judgment result is obtained to complete the external control. The difficulty level of the imagination task was divided by the number of types of body movement imagination and the frequency of occurrence of different body movement imagination types, and the difficulty level of the imagination task was adjusted according to the actual situation of performing movement imagination. The invention also discloses a system, which includes a signal acquisition device, a signal processor, a task processor, an external actuating device and a task presentation device. The invention enables the subject to control the start time of motor imagery, provides step-by-step imagery tasks suitable for individual ability, and greatly improves individual adaptability.

Description

technical field [0001] The invention relates to the technical field of brain-computer interaction, in particular to a brain-computer interaction method and system for imagining body movements. Background technique [0002] In brain-computer interaction technology, motor imagery induces the rise or fall of EEG energy in different rhythms through the subjective motion consciousness of the human brain, that is, the phenomenon of event-related synchronization / desynchronization (ERS / ERD). Different motor imagery tasks can induce different The ERS / ERD pattern is consistent with the normal thinking process of human beings. The currently applied motor imagery brain-computer interaction system generally requires the subject to perform a certain motor imagery task within a fixed period of time. During the imagining process, the subject is in a passive state, unable to control the time of motor imagery autonomously, and the imaginary task is difficult. It is also difficult to match wi...

AI Technical Summary

Problems solved by technology

For example, the patent specification with the announcement number CN103793058B discloses an active brain-computer interaction system motor imagery task classification method and device, based on a single mode method of ERS / ERD, the detection of brain idle and motor imagery states and various motions. The identification of the imaginary state is realized by calculating and extracting ERS / ERD eigenvalues. The uncertainty and diversity of the EEG signal when the brain is in the idle state will directly affect the judgment of the idle state and its duration, and even reduce the perception of the motor imagery state. recognition rate

The patent specification with the publication number CN108597584A discloses a three-stage brain-controlled upper limb rehabilitation method combining steady-state visual evoked potential and motor imagery. Based on the multimodal method of steady-state visual evoked potential (SSVEP) and ERS / ERD, the As a state transition switch, when the state transition switch is turned on, it enters the working state, and uses ERS / ERD to identify the motor imagery state. This method requires the subject to switch between different modes of thinking. The thinking ability and cooperation degree of the patient are relatively high, and the degree of individual applicability is still not high

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