Open and closed cortico-subcortical loops: A neuro-computational account of access to consciousness in the distractor-induced blindness paradigm.
Consciousness and Cognition September 1, 2015 Christian Ebner, Henning Schroll, Gesche Winther et al.
A neuro-computational model explains how the brain gates information into consciousness, specifically in the distractor-induced blindness task. In this task, participants view rapid streams of colored dots and report intervals of coherent motion preceded by a target color. When distractors (motion intervals before the target color) appear, detection of the target motion declines, especially when the delay between target color and target motion is short. The model proposes that conscious perception requires reverberating activity in cortico-subcortical loops, with basal ganglia pathways either allowing or inhibiting this reverberation. Distractors trigger suppression via the inhibitory hyperdirect pathway, and when a target follows closely, lingering suppression prevents its identification. The model reproduces experimental data on how delay length affects detection probability.