Biofeedback in optimizing psychomotor reactivity: II. The dynamics of segmental α-activity characteristics

To estimate the EEG predictors of successful training in the voluntary control of psychomotor reactivity, 29 healthy young (aged 22.3 plus or minus 1.5 years) musical performers were examined. The estimation was carried out in terms of segmental alpha -activity analysis using a biofeedback session as an example, simultaneously stimulating the EEG alpha rhythm and decreasing the muscle tone. On the first day of the study, the musicians followed instructions for the voluntary control of comfortable finger motor activity when performing musical passages for the right hand during a standard performance practice (without any use of an adaptive feedback). On the second day, the muscle tone and the power of the EEG alpha rhythm were voluntarily controlled in the context of a biofeedback technology. The analysis of the unsteady EEG segmentation showed that the dynamics of changes in the coherence and segmental characteristics of the alpha activity were the same for both effective biofeedback training and the standard successful performance practice: an increase in the alpha -rhythm coherence, an increase in the lifetime of alpha spindles, and a decrease in their amplitude variability. The results obtained are discussed in terms of the formation and dissociation of neuron ensembles in central mechanisms of optimal psychomotor functioning.