Interactions Between Discrimination and Control of EEG Alpha

Abstract

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.

Self-Prompted Discrimination and Operant Control of EEG Alpha

“…After obtaining informed consent, participants were given a set of instructions describing strategies to relax and reduce muscle artifact, and the phenomenology of alpha and nonalpha states (Frederick, 2012;Frederick et al, 2015). Participants sat in a cushioned chair with eyes closed in a dimly lit, sound-attenuated room.…”

“…Previous studies found that it was possible to use intertrial time intervals to "cheat" in the standard Kamiya paradigm, although subjects did not make significant use of this information (Frederick, Dunn, & Collura, 2015;Frederick et al, 2016). It is possible that some of the significantly correct performance in the self-prompted discrimination paradigm could be explained by attention to time cues rather than genuine discrimination.…”

“…The lack of relationship between response timing and response performance suggests that self-prompted discrimination may not require complex controlling for the possible use of response timing to "cheat" in the discrimination task (compared to EEG prompted discrimination, Frederick et al, 2015;Frederick et al 2016).…”