Jerzy Bodurka1, Javier Gonzalez-Castillo2, Peter Bandettini1,3
1Functional MRI Facility, National
Institute of Mental Health, NIH, Bethesda, MD, USA; 2Weldon School
of Biomedical Engineering, Purdue University, West Lafayette, IN, USA; 3Section
on Functional Imaging Methods, National Institute of Mental Health, NIH,
Bethesda, MD, USA
In the present study, we employed rtfMRI neurofeedback to investigate whether healthy subjects can learn to self-regulate the variability of the fMRI response in areas affected by high levels of physiological noise. In particular, subjects were asked to attempt to reduce the standard deviation (SDEV) of the fMRI signal in the ventricles and in the posterior sinus. We hypothesized that learning to self-control the variability of the fMRI signal in these extra-cortical areas would be accompanied by increased fMRI time series temporal signal to noise ratio (TSNR=mean voxel time course signal/time course standard deviation) in both white (WM) and gray (GM) matter compartments. Indeed five of six subjects studied were able to self-regulate the variability of the fMRI signal. Our results show: (1) that subjects can actively reduce SDEV of the fMRI signal in the ventricles and the posterior sinus using fMRI neurofeedback; and (2) such SDEV decrease is accompanied by a significant increase of fMRI TSNR in both white and gray matter compartments.