Testing the Specificity of EEG Neurofeedback Training on First- and Second-Order Measures of Attention

During electroencephalography (EEG) neurofeedback training, individuals learn to willfully modulate their brain oscillations. Successful modulation has been shown to be related to cognitive benefits and wellbeing. The current paper addresses the specificity of three neurofeedback protocols in influencing first(basic Stroop effect) and second-order (Gratton effect) measures of attentional control. The data come from two previously presented studies that included the Stroop task to assess attentional control. The three neurofeedback protocols were upregulation of frontal alpha, sensorimotor (SMR), and midfrontal theta oscillations. The results show specific effects of different EEG neurofeedback protocols on attentional control and are modulated by the cognitive effort needed in the Stroop task. To summarize, in less-demanding versions of the Stroop task, alpha training improves firstand second-order attentional control, whereas SMR and theta training had no effect. In the demanding version of the Stroop task, theta training improves first-order, but not second-order control and SMR training has no effect on either. Using a drift diffusion model-based analysis, it is shown that only alpha and theta training modulate the underlying cognitive processing, with theta upregulation enhancing evidence accumulation. Although the current results need to be interpreted with caution, they support the use of different neurofeedback protocols to augment specific aspects of the attentional system. Recommendations for future work are made.