Ongoing spontaneous activity controls access to consciousness: a neuronal model for inattentional blindness.
PLoS Biology June 15, 2016 Stanislas Dehaene, Jean-Pierre Changeux
Even without sensory input, cortical and thalamic neurons exhibit structured spontaneous activity whose origins and functions are unclear. Computer simulations of a simplified model with multiple interconnected thalamocortical columns and long-range excitatory axons reveal two main activity states: spontaneous gamma-band oscillations emerge at a precise threshold controlled by neuromodulator systems, and within a spontaneously active network, sudden "ignition" of one of many possible coherent high-level activity states occurs among cortical neurons with long-distance projections. During ignition, spontaneous activity can block external sensory processing, relating to inattentional blindness, where intensely engaged subjects fail to notice salient but irrelevant stimuli. The minimal network's generic properties may clarify basic cerebral phenomena underlying consciousness's autonomy.