Wandering in brain and mind: how neural dynamics give rise to spontaneous cognition

Humans spend up to half of daily waking life engaged in “mind-wandering,” or inner experiences that are untethered to the immediate sensory environment. How do these experiences arise from the brain’s rich, dynamic patterns of spontaneous activity? In this talk, I will describe our recent insights from fMRI, intracranial EEG, and pupillometry. Using experience sampling and fMRI-based predictive modeling, we have identified a putative neural marker of mind-wandering that centrally involves the default mode network and its dynamic inter-network interactions on the order of tens of seconds. Our intracranial EEG studies—involving directly implanted electrodes in similar networks—have begun to specify, at the millisecond-level, how neuronal population activity is coupled to behavioral and physiological markers of spontaneous inner experience (attentional lapses, pupillary dilation). I will discuss the broad implications of our findings for cognitive neuroscience as well as the interpretation, and future study, of “resting state” spontaneous brain activity in clinical dysfunction.