EEG sLORETA Functional Imaging During Hypnotic Arm Levitation and Voluntary Arm Lifting

Department of Psychology, Lund University, Lund, Sweden.
International Journal of Clinical and Experimental Hypnosis (Impact Factor: 1.38). 01/2012; 60(1):31-53. DOI: 10.1080/00207144.2011.622184
Source: PubMed


This study (N = 37 with high, medium, and low hypnotizables) evaluated depth reports and EEG activity during both voluntary and hypnotically induced left-arm lifting with sLORETA functional neuroimaging. The hypnotic condition was associated with higher activity in fast EEG frequencies in anterior regions and slow EEG frequencies in central-parietal regions, all left-sided. The voluntary condition was associated with fast frequency activity in right-hemisphere central-parietal regions and slow frequency activity in left anterior regions. Hypnotizability did not have a significant effect on EEG activity, but hypnotic depth correlated with left hemisphere increased anterior slow EEG and decreased central fast EEG activity. Hypnosis had a minimal effect on depth reports among lows, a moderate one among mediums, and a large one among highs. Because only left-arm data were available, the full role of the hemispheres remains to be clarified.

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    • "Our study has a number of limitations. For technical reasons, after our global EEG analyses we could not conduct further EEG localization analyses, as we did in another study with the same cohort (Cardeñ a et al., 2012), nor could we carry out spectral analyses comparing all three hypnotizability levels at S1, or analyze EEG activity at other times than those reported here. A study of spectral analysis before and throughout a neutral hypnotic session would be a welcome addition to the literature. "
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