“…The frequency of alpha waves visible in the electrencephalogram (EEG) is a remarkably stable trait in healthy humans with a population standard deviation of only about 1 Hz (Grandy et al ., ; Niedermeyer, ). Larger deviations from this physiological alpha range have been associated with pathological processes, such as deteriorating working memory performance (Klimesch et al ., ; Richard Clark et al ., ), negative symptoms in schizophrenia (Garakh et al ., ), Alzheimer's disease (Moretti et al ., ; Ponomareva et al ., ), or addiction (Domino et al ., ). Alpha frequency, amplitude and phase also show physiological correlations with cognitive performance, visual attention, memory and complex, abstract tasks (Angelakis et al ., ; Busch and VanRullen, ; Hanslmayr et al ., ; Klimesch, ).…”