Self-report during feedback regulation of slow cortical potentials

Area of Science:

• Neuroscience
• Biofeedback Research
• Cognitive Psychology

Background:

• Electrocortical activity, including slow cortical potentials (SCPs) and alpha power, is crucial for cognitive and motor functions.
• Biofeedback training offers a potential avenue for individuals to gain volitional control over their brain activity.
• Understanding the mechanisms of electrocortical self-regulation is key to developing effective therapeutic interventions.

Purpose of the Study:

• To investigate the efficacy of exteroceptive feedback in training bidirectional control of SCPs and alpha power.
• To explore the subjective experiences and physiological correlates associated with successful electrocortical self-regulation.
• To examine whether biofeedback training for SCPs and alpha power can be considered a problem-solving process related to action organization.

Main Methods:

• Participants were trained using exteroceptive feedback to modulate either SCPs or alpha power recorded from the vertex.
• Training involved two sessions, with subsequent assessment of performance on feedback and transfer trials.
• Physiological measures (eye movements, EMG, heart rate) and verbal reports were collected to assess training effects and subjective experiences.

Main Results:

• The SCP group successfully learned to shift slow potentials toward negativity and positivity, demonstrating significant differentiation after training.
• Differentiation of SCPs was associated with somatomotor activation reports during negative SCP trials (p < .01).
• The alpha power group did not achieve significant control over alpha power, but reported emotional arousal (p < .05) and focused vision (p < .08) during alpha suppression trials, suggesting a training effect.

Conclusions:

• Exteroceptive biofeedback can be effective in training voluntary control of slow cortical potentials, potentially involving somatomotor processes.
• While direct control of alpha power proved challenging, training induced subjective changes indicative of altered arousal and attention.
• Electrocortical biofeedback tasks can be conceptualized as problems of action organization that individuals actively attempt to solve.