Interactions Between Discrimination and Control of EEG Alpha

The relationship between discrimination and control of physiological states is largely unexplored, although it is often suggested that this relationship is important for the mechanism of action of biofeedback. This pilot study examined 6 participants given seven sessions of alpha discrimination training combined with standard neurofeedback “control” training. Four subjects achieved five criterion (binomial p < .05) sessions in the discrimination task. The discrimination task performances correlated significantly with performance in the amplitude control task. Evidence that some subjects can use the intertrial interval (ITI) to predict the correct responses in the discrimination task led to an examination of how ITIs were distributed with respect to success (correct or incorrect) and type of trial (same or different from previous) in these and 40 additional subjects from archival data (Frederick, 2012). This analysis found that some information about the correct responses was conveyed by the ITI, but participants made relatively little use of this information. However, the criterion discrimination sessions showed dramatic changes in the distribution of ITIs in the present (but not the archival) study, suggesting that participants were controlling their electroencephalogram (EEG) during these sessions. These findings provide preliminary evidence of generalization of skills between these two tasks.