Thresholds and emergent processes of visual consciousness on color and category in preschoolers and adults

Understanding how perception transitions from an unconscious to conscious state is a central aim of visual consciousness research. The threshold is the boundary at which consciousness arises, and the process from unconsciousness to consciousness is the emergent process. Although studies have investigated the thresholds and emergent processes of visual consciousness in adults, how these processes develop during childhood remain unknown. Seventeen 5-6-year-old preschoolers and 16 adults completed two discrimination tasks (color and category) with varying stimulus onset asynchronies (SOAs; 16.7-216.7 and 16.7-83.3 ms respectively). Objective discrimination accuracy was recorded, and subjective awareness was assessed via a four-point Perceptual Awareness Scale. Data were fitted with a four-parameter non-linear psychometric function to estimate each participant's threshold and gradualness (center and range of the slope, respectively). Thresholds of objective discrimination and subjective awareness were significantly larger in preschoolers, without the main effect of task or interaction between age and task. Furthermore, both emergent processes were significantly more gradual in preschoolers. Therefore, visual consciousness of color and category emerged at larger thresholds and more gradually in preschoolers, with no differences in task performance. Hence, preschoolers experience consciousness of colors and objects more gradually and slowly than adults.