The Involvement Of The Thalamus In The Modulations Of Background Color On Conflict Adaptation

We are all in the changing life environment. To meet the rapid changing environmental demand, the individual need adjust cognitive processing strategy, which is the online adjustment of cognitive control. The background color is an important environmental factor. Lines of investigations have suggested that color has its effect on human cognition and behavior. The impact of background color on the online of cognitive control is an un-ignored but essential issue and the direct evidence that explores the neural mechanisms through which color operates is little in the task-state functional magnetic resonance imaging (fMRI) research. Interestingly, our one pilot study indicated that the conflict adaptation effect disappeared when the screen context color was blue, while it was significant when the screen context color was red. To further examine the replication of the phenomenon and reveal the neural mechanism through which the background color modulates the conflict adaptation effect, we collected fMRI data of subjects during performance of the flanker task across gray, blue, and red backgrounds. It is noted that gray or black is the typical background of flanker task. Results showed that behaviorally, significant conflict adaptation effect was associated with gray and red backgrounds, while it disappeared in blue background. Imaging activated data indicated that the thalamus displayed a significant the background color type (gray, blue, and red)× previous trial congruency (congruent and incongruent)× the current trial congruency (Congruent and Incongruent) interaction and the thalamic activation patterns were dissociable across gray/red and blue backgrounds, corresponding with their behavioral data. Psychophysiological interaction analysis showed that the thalamus displayed stronger coupling with the right inferior frontal gyrus during the low conflict resolution trials vs. the high conflict resolution trials in gray/red backgrounds as compared with in blue background. Besides, the beta estimate of the thalamus-IFG coupling could predict behavioral reduced interference in gray/red backgrounds. Previous investigations have suggested that the activation of thalamus is associated with the alerting function of the attentional network. Besides, our results of Experiment 2 indicated that the alerting scores of the blue background were significantly lower than that of the gray/red background, which suggested that the alerting function was modulated by the background color. These data suggest that the background color may mediate the processing of conflict adaptation by the thalamic influence.