The Effects of a Single Session of Upper Alpha Neurofeedback for Cognitive Enhancement: A Sham-Controlled Study

Abstract

The minimization of the non-specific factors of neurofeedback (NF) is an important aspect to further advance in the understanding of the effects of these types of procedures. This paper investigates the NF effects of a single session (25 min) of individual upper alpha enhancement following a sham-controlled experimental design (19 healthy participants). We measured immediate effects after the training and 1-day lasting EEG effects (eyes closed resting state and task-related activity), as well as the event-locked EEG effects during the execution of a mental rotation task. These metrics were computed in trained (upper alpha) and non-trained EEG parameters (lower alpha and lower beta). Several cognitive functions were assessed such as working memory and mental rotation abilities. The NF group showed increased upper alpha power after training in task-related activity (not significantly sustained 1 day after) and higher pre-stimulus power during the mental rotation task. Both groups improved cognitive performance, with a more prominent improvement for the NF group, however a single session seems to be insufficient to yield significant differences between groups. A higher number of training sessions seems necessary to achieve long-lasting effects on the electrophysiology and to enhance the behavioral effects.

Cognitive Performance Enhancement: Do Biofeedback and Neurofeedback Work?

“…So, future research is warranted to further elaborate in a systematic manner on the potential impact of potential confounding factors (e.g., small sample sizes such as in Rasey et al 1995, see below for more details on confounding factors). Besides that, as suggested earlier by Gruzelier (2014b, c), placebo is still rarely used as we encountered it in only six studies (i.e., Bazanova et al 2013;Escolano et al 2014;Guez et al 2015;Hsueh et al 2016;Kober et al 2015;Wang and Hsieh 2013) to demonstrate the statistical superiority of the effect on the NFB training. However, according to the guidelines for the evaluation of clinical efficacy of psychophysiological interventions, the inclusion of control and placebo or sham feedback groups would enhance the validity within the current research field on NFB training (La Vaque et al 2002).…”

“…However, this effect could not be sustained 1 day later. With regard to cognitive performance, Escolano et al (2014) found a significant improvement in the upper alpha training group as well as the sham group. Nevertheless, the improvement was larger in the augment group than the sham group.…”

“…In the subjects with a high baseline resting alpha frequency, however, no effect on the resting alpha power, the cognitive performance or HRV was observed . Escolano et al (2014) investigated the effects of a single upper alpha augment training session on specific cognitive functions in a double-blind sham-controlled experimental design. The results indicated that the augment group showed increased alpha power after training in task-related activity and higher prestimulus power during the mental rotation task.…”

A Comparison of the Effectiveness of Neurofeedback (NFB) Training Method and Fernald’s Multisensory Approach on Dictation Performance among Students Suffering from Dictation Disorder (Dysgraphia)

“…One of these important factors is long-term memory. Recent studies have shown that neurofeedback training method is an effective intervention in improving decreased levels of student's memory struggled with dictation disorder [6,9,[27][28][29][30][31][32][33][34][35][36][37].…”

A Comparison of the Effectiveness of Neurofeedback (NFB) Training Method and Fernald’s Multisensory Approach on Dictation Performance among Students Suffering from Dictation Disorder (Dysgraphia)

“…One of these important factors is long-term memory. Recent studies have shown that neurofeedback training method is an effective intervention in improving decreased levels of student's memory struggled with dictation disorder [6,9,[27][28][29][30][31][32][33][34][35][36][37].…”