Connectivity-based neurofeedback: Dynamic causal modeling for real-time fMRI

Abstract

Neurofeedback based on real-time fMRI is an emerging technique that can be used to train voluntary control of brain activity. Such brain training has been shown to lead to behavioral effects that are specific to the functional role of the targeted brain area. However, real-time fMRI-based neurofeedback so far was limited to mainly training localized brain activity within a region of interest. Here, we overcome this limitation by presenting near real-time dynamic causal modeling in order to provide feedback information based on connectivity between brain areas rather than activity within a single brain area. Using a visual–spatial attention paradigm, we show that participants can voluntarily control a feedback signal that is based on the Bayesian model comparison between two predefined model alternatives, i.e. the connectivity between left visual cortex and left parietal cortex vs. the connectivity between right visual cortex and right parietal cortex. Our new approach thus allows for training voluntary control over specific functional brain networks. Because most mental functions and most neurological disorders are associated with network activity rather than with activity in a single brain region, this novel approach is an important methodological innovation in order to more directly target functionally relevant brain networks.

Real-Time Functional Connectivity-Informed Neurofeedback of Amygdala-Frontal Pathways Reduces Anxiety

“…Findings may reflect that subjects explored different regulation strategies during the initial 2 runs and maintained the successful strategies during the subsequent training runs. This difference to BOLD activity NFT studies may be explained by the fact that the functional connectivity feedback signal inherently comes at a longer delay and involves higher dimensionality [71, 72], which may lead to a higher difficulty for the subjects to discover successful regulation strategies. Future studies may increase the number of training runs and sessions to determine whether regulatory control on the neural level can be further increased.…”

Neurofeedback, Self-Regulation, and Brain Imaging: Clinical Science and Fad in the Service of Mental Disorders

“…In fact, participants in some fMRI-nf studies can modulate their brain in the first trial [92][93][94][95][96]. Thus, experimental designs that lack a no-feedback or sham-feedback control cannot dissociate whether the change from baseline relies on feedback or the initial mental strategy.…”

“…Moreover, few fMRI-nf experiments directly probe therapeutic outcomes. Some clinicians, nonetheless, refer patients to neurofeedback training programs that last more than six months, include as many as 40 sessions, and generally cost between $4,000 to $10,000 ( participants to modulate connectivity between visual and parietal cortex [94].…”

The self-regulating brain and neurofeedback: Experimental science and clinical promise

“…(Vollebregt, van Dongen-Boomsma, Buitelaar, & Slaats-Willemse, 2014, 15. (Koush et al, 2013), 16. (Florin, Bock, & Baillet, 2014, 17.…”