Spontaneous repetitive thoughts can be adaptive: postscript on "mind wandering".

When researchers use the term mind wandering for task-unrelated thoughts in signal detection tasks, we may fall into the trap of believing that spontaneous thoughts are task unrelated in a deeper sense. Similar negative connotations are attached to common terms like cognitive failures, resting state, rumination, distraction, attentional failures, absent-mindedness, repetitiveness, mind lapses, going AWOL in the brain, cortical idling, and the like. Nevertheless, it seems obvious that mathematicians and scientists often engage in spontaneous repetitive thoughts and that the results of those thoughts are by no means maladaptive. Yet that seems to be implied by the standard use of common terms in the research literature. As humans, we know that spontaneous ideation goes on during all of our waking hours, during dreams and even in slow-wave sleep. It is unlikely that such a great allocation of mental resources has no useful adaptive function. This view of the spontaneous stream is consistent with the perspective of global workspace theory on conscious contents, which suggests that conscious events are not like unconscious cognitive representations. Rather, conscious events trigger widespread adaptive changes in the brain, far beyond their cortical origins. The brain evidence for such "global broadcasting" triggered by conscious (but not matched unconscious) events throughout the cortex is now quite compelling. Spontaneous conscious thoughts, even if they appear to be arbitrary, irrelevant, unwanted, or intrusive, may still play an important adaptive role in life-relevant problem solving and learning.