Daydreaming, Thought Blocking and Strudels in the Taskless, Resting Human Brain’s Magnetic Fields

The incidence, i(S), and duration, l(S), of transient, intermittent, hierarchical vorticities, strudels, S, in magnetic flux fluctuations, were computed from MEG records. from 91 task‐free resting subjects. The MEG’s i(S) and l(S) manifested characteristic times and entropic sensitivity resembling those reported in psychological studies of daydreaming and task‐unrelated thoughts, TUTs. Transient reduction or absences of strudels can be found in patients with syndromes characterized by thought blocking. Positive ergodic single orbit measures of expansiveness and mixing predict i(S) and l(S). An analogy with the relationship between intermittent pontine‐geniculate‐occipital waves and dreaming is made to strudels with daydreaming. Both can be interpreted as neurophysiological correlates of the spontaneous intrusions into consciousness of the never idle unconscious mind.