The Signal Processing And Analysis Of EEG Evoked By Visual-Auditory Based On Emotional Cognition

Using human brain's the methods of cognition and information processing,we can significantly improve the computer processing emotional information's ability and efficiency.More and more researchers pay attention on Human-computer emotional interaction,thus emotional brain cognition has become a research hotspot.When people get the emotional information from visual and auditory,the brain completes the emotions' understanding and cognitive tasks through synergistic interaction between different brain regions.So far the brain synchrony activity mechanism of visual and auditory evoked emotion is not entirely clear and the further research on EEG signal feature extraction and synchrony analysis is also inadequate.These restrict the computer to effectively identify and understand emotions.In order to research EEG features and synergistic effect between different brain regions,this paper designed an experimental paradigm for audio-visual stimuli based on six basic emotions(pleasure,anger,sadness,surprise,disgust,fear).Through the EEG signal acquisition and EEG feature extraction.Under the different emotional states,we analyze the synergy of EEG signal on synchronization,coupling and coherence.We also deeply analyzed the emotional brain cognition.The details are as follow:(1)Using E-prime software,we designed an audio-visual stimuli experimental paradigm based on six basic emotions(happiness,anger,sadness,surprise,disgust,and fear),and used Neuroscan40 lead brain event related potentials instrument synchronously acquired EEG signal(2)Through preprocessing,we removed ocular and baseline artifacts,the effect of spontaneous EEG to get audio-visual evoked EEG signal.Then,we used the t-test method to analyse the significant difference between different leads.(3)The Hilbert transform was used to get the phase of the EEG feature signal which was extracted by Wavelet transform.Then we used the phase synchronization index to analyze the synchronization of brain electrical activity.Through analyzed the phase synchronization index of ? rhythm which was thought to be related to emotional processing,we explained the mechanism of synchronous activity of EEG evoked by audio-visual emotion.(4)The Bispectrum and Bicoherence Spectrum were used to extract feature and analyze the phase-coupling of different EEG rhythms,respectively.The result shows that Emotion cognition activity is not only related to phase-coupling between ?-? rhythms but also related to y rhythm. Phase-coupling of(3 rhythm was increased only when the stimulus was the positive emotion.(5)We used Wavelet coherence to analyze coherence of y rhythm,which had close relation with brain cognition.Through the analysis,we explored the interaction and connectivity between different brain regions when brain was doing the emotional cognition.This paper's research methods and achievements can be used to affective computing and recognition,human computer interaction and emotion robot.It can promote the development of neural information processing,and lay the foundation for the research of brain cognitive science and artificial intelligence.It has dual value of science and Application.