Russell W. Chan1,
2, Iris Y. Zhou1, 2, Y. X. Liang3,
Yong Hu4, K. F. So3, Ed X. Wu1, 2
1Laboratory
of Biomedical Imaging and Signal Processing, The University of Hong Kong,
Hong Kong SAR, China; 2Department of Electrical and Electronic
Engineering, The University of Hong Kong, Hong Kong SAR, China; 3Department
of Anatomy, The University of Hong Kong, Hong Kong SAR, China; 4Department
of Orthopaedics & Traumatology, The University of Hong Kong, Hong Kong
SAR, China
Previously, a case study reported that complete transection of the corpus callosum induced loss of interhemispheric correlations in resting-state functional connectivity MRI (RSfcMRI). However, the results were limited by the lack of any electrophysiological recordings. Therefore, it could not be excluded that the loss of interhemispheric correlations in RSfcMRI might arise due to non-neuronal physiological modulations. In this study, intra-cortical electroencephalography (EEG) signals were recorded in the complete corpus callosotomy rats to understand the neural origin of the loss of interhemispheric correlations in RSfcMRI. The results clearly supported that the loss of interhemispheric correlations in RSfcMRI reflects the changes in spontaneous brain activity and its coherence. More importantly, the results strongly suggested that resting-state spontaneous fluctuations have strongest correlation with delta oscillations.