Attention neuroenhancement through tDCS or neurofeedback: a randomized, single-blind, controlled trial

Abstract

Neurofeedback and transcranial Direct Current Stimulation (tDCS) are promising techniques for neuroenhancement of attentional performance. As far as we know no study compared both techniques on attentional performance in healthy participants. We compared tDCS and neurofeedback in a randomized, single-blind, controlled experiment assessing both behavioral (accuracy and time reaction) and electrophysiological (N1, P1, and P3 components) data of participants responding to the Attention Network Task (ANT). Eighty volunteers volunteered for this study. We adopted standard protocols for both techniques, i.e., a Sensorimotor Rhythm (SMR) protocol for neurofeedback and the right DLPFC anodal stimulation for tDCS, applied over nine sessions (two weeks). We did not find significant differences between treatment groups on ANT, neither at the behavioral nor at the electrophysiological levels. However, we found that participants from both neuromodulation groups, irrespective of if active or sham, reported attentional improvements in response to the treatment on a subjective scale. Our study adds another null result to the neuromodulation literature, showing that neurofeedback and tDCS effects are more complex than previously suggested and associated with placebo effect. More studies in neuroenhancement literature are necessary to fully comprehend neuromodulation mechanisms.

Anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex improves attentional control in chronically stressed adults

“…Moezzi et al (2021) found that tDCS over the left Dorsolateral Prefrontal Cortex (DLPFC) for five consecutive days improved attentional control in healthy individuals, as measured by an increase in P600 amplitudes and a decrease in reaction time in an Integrated Visual and Auditory-Adult Edition (IVA-AE) Task (Moezzi et al, 2021). A study by Rêgo et al (2022) found similar results. tDCS over the left DLPFC improved sustained attention in healthy individuals.…”

“…tDCS over the left DLPFC improved sustained attention in healthy individuals. The results showed that tDCS over the left DLPFC enhanced reaction and P2 amplitudes in a visual flanker task, indicating an improvement in sustained attention after the stimulation ( Rêgo et al, 2022 ). Moreover, tDCS has been shown to have beneficial effects on stress-related cognitive impairments.…”

BCI Applications to Creativity: Review and Future Directions, from little-c to C2

“…In addition to allowing for an intense and original creative experience, the system also allows for the collection of data on implicit learning and the interplay between conscious and unconscious processes. Finally, it could be used as a tool to increase attentional focus [ 1 ], to support learning processes [ 4 ], and as a creative warm-up [ 5 , 7 ].…”

“…Another possible use of a BCI is in neurofeedback, which is the modulation of cerebral activity during a task based on certain feedback about the ongoing EEG. It can be used, for example, to improve focal attention [ 1 ], working memory [ 2 ], emotional management [ 3 ], learning [ 4 ], and creative thinking [ 5 ] in both experimental and real-life contexts. In addition, multiple settings can be implemented.…”