Self-regulation of inter-hemispheric visual cortex balance through real-time fMRI neurofeedback training.

article i nfo Article history: Accepted 27 May 2014 Available online 4 June 2014 Recent advances in neurofeedback based on real-time functional magnetic resonance imaging (fMRI) allow for learning to control spatially localized brain activity in the range of millimeters across the entire brain. Real- time fMRI neurofeedback studies have demonstrated the feasibility of self-regulating activation in specific areas that are involved in a variety of functions, such as perception, motor control, language, and emotional pro- cessing. In most of these previous studies, participants trained to control activity within one region of interest (ROI). In the present study, we extended the neurofeedback approach by now training healthy participants to control the interhemispheric balance between their left and right visual cortices. This was accomplished by pro- viding feedback basedon thedifference inactivity betweenatarget visual ROI and thecorrespondinghomologue region in the opposite hemisphere. Eight out of 14 participants learned to control the differential feedback signal over the course of 3 neurofeedback training sessions spread over 3 days, i.e., they produced consistent increases in the visual target ROI relative to the opposite visual cortex. Those who learned to control the differential feed- back signal were subsequently also able to exert that control in the absence of neurofeedback. Such learning to voluntarily control the balance between cortical areas of the two hemispheres might offer promising rehabilita- tion approaches for neurological or psychiatric conditions associated with pathological asymmetries in brain ac- tivity patterns, such as hemispatial neglect, dyslexia, or mood disorders.