Teachers' ability to critically reflect classroom situations in relation to their own actions constitutes an important prerequisite to improve teaching performance and professional behavior. This study investigated electroencephalogram activity in the alpha band during a reflection task before and after training in a sample of preservice teachers. Reflection was associated with stable brain activity patterns over two separate time points of assessment. Increased alpha power during reflection of pedagogically relevant scenarios was found at occipital sites, especially in participants with higher reflection competence. This is consistent with prior studies that showed increased alpha power during mental imagery among other tasks. Training of reflection competence, administered in a subsample of participants, was accompanied by increased reflection performance, while no intervention-related effects were found at the neurophysiological level. The findings of this study provide first preliminary evidence of increased alpha power at occipital sites as a neurophysiological indicator of reflections of pedagogically relevant educational scenarios.