In an unpublished study* (in press), researchers report that home-based neurofeedback training (“tele-neurofeedback”) leads to significant improvements in sleep for participants with insomnia. A electromyography (EMG) biofeedback group (“tele-biofeedback”) was used as a comparison group. Seventeen participants were randomly assigned to a neurofeedback (n=9) or biofeedback condition (n=8), and 12 control subjects (i.e., healthy sleepers) were used to compare baselines measures. The researchers used a novel and brilliant design whereby each group (neurofeedback and biofeedback) received the exact same electrode set up and training screen at each session, but, of course, the electrodes measured different variables (EEG vs. EMG). This allowed for participants to be blinded to their condition.
Participants in the neurofeedback group (3 women and 6 men; mean age = 41) and biofeedback group (3 women and 5 men; mean age = 43) received approximately 20 sessions of training and all participants were medication free 4 weeks prior and throughout the study. The biofeedback protocol called for relaxation training via reduction of EMG at Fpz. Neurotherapy utilized the now classic Cz/SMR training protocol, which enhances 12-15Hz (SMR) and inhibits 4-8Hz (theta) and 20-30Hz (high beta). As you may recall, we previously reported on the successful application of SMR to sleep. Participants completed a wide variety of pre/post objective and subjective assessments, such as bedtime dairies, sleep logs, EEGs (polysomnography), Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Athens Insomnia Scale, State Trait Anxiety Index, Beck Depression Inventory, Presleep Arousal Scale with a somatic and a cognitive subscale, and the Mini International Neuropsychiatric Interview. Outcome measures included total sleep time, sleep latency, wake after sleep onset, sleep efficiency, and time in bed.
Participants in the neurofeedback group experienced statistically significant reductions in sleep latency (39%) and waking after sleep onset (53%) in a within group pre-post analysis. While participants in the biofeedback condition also reported decreases in sleep latency (44%) and waking after sleep onset (13%), only participants in the neurofeedback group realized significant improvements in rapid eye movement (REM) sleep, total sleep time, and time in bed. Effect sizes ranged from small to medium; however, there is no surprise here given the small sample. I suspect larger effect sizes could be realized with a bigger sample size.
The researchers hypothesized that:
“Applying a NFB protocol intervening on the level of cognitive processing, may thus have had an influence on cortical arousal and information processing during sleep, resulting in an increase of TST [total sleep time]. On a more concrete level, by inhibiting high beta (20-30Hz) during NFB [neurofeedback] training we tried to intervene directly on the reactivity to stress and arousal. Furthermore, Sterman et al.  showed that the increase of SMR resulted in a facilitation of sleep spindle bursts and quiet sleep. This in turn might have had an influence on the consolidation of sleep in our subjects and might explain the positive impact on sleep duration that we observed” (pg. 18-19).