Volume 124, Part A, 1 January 2016, Pages 214–223 •We trained regulation of the left DLPFC BOLD signal with rt-fMRI neurofeedback.•Self-control over left DLPFC increased significantly across five days of training.•We examined WM performance before and after rt-fMRI and n-back training.•WM in the n-back plus rt-fMRI group improved more than the n-back control group.•Self-regulating the BOLD signal in DLPFC may have cognitive benefits.Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback can be used to train localized, conscious regulation of blood oxygen level-dependent (BOLD) signals. As a therapeutic technique, rt-fMRI neurofeedback reduces the symptoms of a variety of neurologic disorders. To date, few studies have investigated the use of self-regulation training using rt-fMRI neurofeedback to enhance cognitive performance. This work investigates the utility of rt-fMRI neurofeedback as a tool to enhance human cognition by training healthy individuals to consciously control activity in the left dorsolateral prefrontal cortex (DLPFC).

A cohort of 18 healthy participants in the experimental group underwent rt-fMRI neurofeedback from the left DLPFC in five training sessions across two weeks while 7 participants in the control group underwent similar training outside the MRI and without rt-fMRI neurofeedback. Working memory (WM) performance was evaluated on two testing days separated by the five rt-fMRI neurofeedback sessions using two computerized tests. We investigated the ability to control the BOLD signal across training sessions and WM performance across the two testing days. The group with rt-fMRI neurofeedback demonstrated a significant increase in the ability to self-regulate the BOLD signal in the left DLPFC across sessions. WM performance showed differential improvement between testing days one and two across the groups with the highest increases observed in the rt-fMRI neurofeedback group. These results provide evidence that individuals can quickly gain the ability to consciously control the left DLPFC, and this training results in improvements of WM performance beyond that of training alone.

New techniques to induce and control neural plasticity hold the promise of enhancing recovery from brain injury (Jenkins and Merzenich, 1987 and Wieloch and Nikolich, 2006), combating brain disease (Baroncelli et al., 2011 and Sakas et al., 2007), and even improving human performance in healthy subjects (Buschkuehl et al., 2008, Garlick, 2002, Jaeggi et al., 2011 and Jausovec and Jausovec, 2012). A number of methods are being explored to induce and control neuroplastic processes, including cognitive training (Kleim et al., 2004, Oleson et al., 2004 and Pleger et al., 2003), pharmacotherapy (Delacour et al., 1990, Ehrenreich et al., 2008 and Greuel et al., 1988), electrical and magnetic stimulation (Fraser et al., 2002, McKinley et al., 2013, Pascual-Leone et al., 1998 and Ziemann et al., 2002), and self-modulation of brain regions and networks based on neurofeedback (Birbaumer and Cohen, 2007, Daly and Wolpaw, 2008 and Ros et al., 2010). Of these techniques, self-modulation methods have the advantage of no known side effects, as well as straightforward translation to neurophysiological exercises that could be performed at home without the use of sophisticated equipment and trained professionals (Mak and Wolpaw, 2009 and Vaughan et al., 2006).

Real-time functional magnetic resonance imaging (rt-fMRI) has been enabled by recent advances in image acquisition, reconstruction, and display of the blood oxygen level-dependent (BOLD) signal. This technique can be used as a tool to deliver region-specific neurofeedback. A number of previous studies have demonstrated the efficacy of rt-fMRI neurofeedback to elicit self-control of localized BOLD signals (Sulzer et al., 2013a) although few show an impact on behavior or cognition. winix air purifier lowesdeCharms et al. (2005) applied a controlled rt-fMRI neurofeedback study to influence symptoms of chronic pain. oreck air purifier burning smellIn their study, significant changes in pain perception and chronic pain were produced by learning to control BOLD signals from the rostral anterior cingulate cortex (rACC). trion electronic air cleaner ozone

Rota et al. (2009) used rt-fMRI neurofeedback of right inferior frontal gyrus (IFG) to improve accuracy on emotional prosodic intonation. Right IFG modulation did not, however, influence syntactic processing. Sham rt-fMRI neurofeedback of the right IFG impeded learning processes in a control group. Ruiz et al. (2013) trained self-regulation of the bilateral anterior insula through rt-fMRI neurofeedback in a group of schizophrenia patients. The success of self-regulation was negatively correlated with negative symptoms and duration of illness. In addition, patients detected significantly more disgust faces in a post-training face emotion recognition evaluation. Young et al. (2014) performed rt-fMRI neurofeedback of the left amygdala on a group of unmedicated patients suffering from major depressive disorder. Significant reductions in self-reported measures of depression, anxiety, anger, restlessness and irritability were measured. A significant increase in the rating of happiness was also observed.

These encouraging results demonstrate that direct control over neurophysiology can influence behavior and cognition.We hypothesized that rt-fMRI neurofeedback can be used to learn self-regulation over the BOLD signal in the left DLPFC. Learning self-regulation from rt-fMRI neurofeedback has produced significant behavioral effects (deCharms et al., 2005, Haller et al., 2010, Linden et al., 2012, Rota et al., 2009, Ruiz et al., 2013, Scharnowski et al., 2012, Shibata et al., 2011, Sitaram et al., 2012, Subramanian et al., 2011, Young et al., 2014 and Zhang et al., 2013a) resulting from neuroplastic changes of learned self-regulation. Lee et al. (2011) reported that neurofeedback training reinforces pertinent functional networks while extraneous connections are weakened. Haller et al. (2013) exhibited that neurofeedback learning is mediated by widespread alterations in learning networks and the application of learned self-regulation involves more limited and specific network changes. These changes are described by the Hebbian theory which details neuroplasticity during the learning process (Hebb, 1949).

Neuroplasticity is engaged through the repetitive stimulation of the postsynaptic cell from the presynaptic cell. In short, the synapses of neurons firing together are reinforced resulting in an increase in synaptic efficiency. The left dorsolateral prefrontal cortex (DLPFC) plays an important role in working memory (WM; D'Esposito et al., 2000) and higher levels of attentional control (Posner and Presti, 1987). Thus, we hypothesize that self-regulation of the left DLPFC would lead to improved synaptic efficiency of the WM and attentional control networks. These changes would lead to improved performance on tasks that rely on WM and attentional control beyond that of training alone. To test these hypotheses, we examined the effect of rt-fMRI neurofeedback on control over the BOLD signal in the left DLPFC as well as pre- and post-training performance of n-back WM, prospective WM, and vigilance tasks.Prior to being enrolled, each participant completed a telephone screening to qualify for the study.