With Like Mental Tasks In Eeg Research, Space And Frequency Domain Features

1. PurposeAs a part of the doctoral research program of higher education (project No.20060026006), this article is for the second stage of study on the characters of Objective Thinking in Qigong practice in terms of brain electrical activity and its psychological and physiological related characters. In the first stage of this program, it has been proved that Objective Thinking is another way of thinking, apart from Abstractive Thinking and Imaginative Thinking. By comparing the results of Electroencephalogram (EEG) in three ways of thinking, the second stage tends to discover the characters in terms of the intensity and ordering of brain-electrical signal, the location in encephalic regions and its related characters, in order to define the brain electrical activity in Objective Thinking. Therefore, this study will provide evidences with more sufficient scientific experiments that could be used in the study of Objective Thinking in the fields, such as Chinese Medicine, Qigong and Psychology etc.2.MethodsBy applying the model proposed by Professor Liu Tianjun on Qigong experimental study known as "Two-way layout, correlated detection and mutual paraphrase." Following the standards of taking samples and the plan of experimental design, there were total of 33 undergraduate students had been selected to take the EEG tests designed for testing in different ways of thinking, after over three times of systematic training. The testing equipment used is MR-31, made in Japan. And the software for collecting and analysing data adopted is ATAMAP. II for windows, provided by Tokyo Denki University, Japan. The data processing work was fulfilled by the Biological Engineering Llab of Beijing University of Posts and Telecommunications. By adopting the methods of wavelet domain de-noising and wavelet packet, total six of frequency bands had been resolved,δ(0.8-3. 1Hz),θ(3.9-7.0Hz).α1 (7.8-10.2Hz),α2 (10.2-13.2Hz),β1(14.1-19.5Hz),β2(20.3-29.6Hz), also for the population and average capacity and correlation coefficient and wavelet entropy data. Using the statistic software of SPSS13.0 and adopting the method of multivariate analysis of variance, there are three sets of variance had been analysed respectively in the resting state of three ways of thinking as follows:①average capacities;②the correlation coefficient;③wavelet packet.3.Results(1)Variances on the average capacity in the resting state of different ways of thinking0The comparison on the variances explains the degree of change in terms of the population and average capacity in the resting state of different ways of thinking.It turns out that, in the population band, the average capacity of EEG is significant higher in Objective Thinking comparing to Abstractive Thinking. The variance (P<0.01) is highly significant. In terms of the number of leads, both for Objective Thinking and Imaginative Thinking, the numbers increased for most of the parts, the rest reduced. Regards to Abstractive Thinking, the numbers all reduced; inδband, the average capacity of EEG is significant higher in Objective Thinking comparing to Imaginative Thinking. The variance (P<0.01) is highly significant. In terms of the number of leads, for Objective Thinking, the numbers increased at Fp1 & Fp2, the rest reduced. Regards to Abstractive Thinking and Imaginative Thinking, the numbers all reduced; inθ&α2 band, the average capacity of EEG is not significant among three ways of thinking(P>0.05); inα1,β1 &β2 band, the average capacity of EEG is significant higher in Objective Thinking comparing to Abstractive Thinking. The variance (P<0.001) is extremely significant. In terms of the number of leads, both for Objective Thinking and Imaginative Thinking, the numbers increased for most of the parts, the rest reduced. Regards to Abstractive Thinking, the numbers all reduced.(2) Variances on the correlation coefficient of different ways of thinkingThe comparison on the variances explains the correlation of leads in terms of the population and respective bands of different ways of thinking.According to the correlation coefficients in the leads of the population bands, the correlation is high in Objective Thinking at Fp2, Fp1, F8 and Fz; and also high at O1, T5 & Pz. In a2 band, it shows a significant correlation among the area of right central area (C4) with frontal midline point (Fz); inβ1 band, it shows a significant correlation between Fp1 & Fp2; the same inβ2 band in the areas of Fz, Fp2, C4 and F8.In the population and other bands, the result shows the number of the low correlation leads is less in the state of Objective Thinking than any of the other ways. It reveals that Objective Thinking shows highly significant correlation among the leads of the brain.(3) Variances on the wavelet entropy in the resting state of different ways of thinkingThe comparison on the variances explains the wavelet entropy of population in the resting state of different ways of thinking.It shows the wavelet entropy is lower in Objective Thinking comparing to Imaginative Thinking, there is a significant variance between these two (P<0.001). And it is higher than Abstractive Thinking. The variance is also significant (P<0.01). In terms of the number of leads, it increased partially at the points of Fp1,Fp2,C3,O1,F7,T5,Pz and reduced at the points of C4,O2,F8,T6,Fz. Regards to Imaginative Thinking, the numbers are all increased. And for Abstractive Thinking, the numbers are all reduced.4. ConclusionsThe conclusions of the study include the following aspects: (1)Features on the activity and spatial & frequency characters of EEG in Objective ThinkingThe activity of EEG is increasing. Comparing with Imaginative Thinking, inδband, it becomes more active in Objective Thinking; comparing with Abstractive Thinking, inα1,β1 &β2 band, it becomes more active in Objective Thinking. In terms of spatial character, it reveals strong activity in the points of Fp1 & Fp2, also F7 & F8, and less activity in the points of O1 & O2,T5 & T6.(2)Features on the correlation and spatial & frequency characters of EEG in Objective ThinkingThe correlation in Objective Thinking is highly significant. In the population bands, the correlation is high in Objective Thinking at right front area including Fp2, Fp1, F8 and Fz. This points out a trend of generally high correlation in the right hemisphere around the point of Fp2. It shows high correlation inα2,β1 andβ2 band in the forehead and right hemisphere.(3)Features on the ordering and spatial characters of EEG in Objective ThinkingThe ordering of EEG shows a bi-directional change. In terms of spatial characters, the ordering of forehead and left hemisphere reduced, the signal is high complexity. The ordering of right hemisphere is high, the signal is less complexity.