LAUSR

Recent studies have reported on the feasibility of real-time functional magnetic resonance imaging neurofeedback (rtfMRI-nf) training. Although modulation of BOLD signal of single brain regions in rtfMRI-nf is a well established technique, the same does not hold true for modulation of connectivity. Self-modulation of interregional connectivity is a potential alternative in clinical neuroscience applications, since long-range functional dysconnectivity is being increasingly recognized as a mechanism underlying neuropsychiatric disorders. In this study, a framework was designed to train participants to self-regulate, in real time, interhemispheric functional connectivity between bilateral premotor cortices. To this end, participants use a novel adaptive motor imagery task, with gradual frequency variation preventing activity plateaus and subsequent decreases in correlation of activity (3 NF runs). Participants were able to upregulate and maintain interhemispheric connectivity using such adaptive approach, as measured by correlation analysis. Modulation was achieved by simultaneous volitional control of activity in premotor areas. Activation patterns in the downregulation condition led to significantly lower correlation values than the ones observed in the upregulation condition, in the first two NF runs. Comparison between runs with and without feedback, showed enhanced activation in key reward, executive function, cognitive control regions, suggesting neurofeedback promotes reward and the development of goal-directed behavior. This proof-of-principle study suggests that functional connectivity feedback can be used for volitional self-modulation of neuronal connectivity. Functional connectivity based neurofeedback could serve as a possible therapeutic tool in diseases related to the impairment of interhemispheric connectivity, particularly in the context ot motor training after stroke.