Left Insula and Right Middle Temporal Gyrus Dominate Cortical Network Discriminating Arousal-dependent Emotions

Emotion processing is an integral part of everyone's life. The basic neural circuits involved in emotion perception are becoming clear, though the emotion's cognitive processing remains under investigation. Utilizing the stereo-electroencephalograph with high temporal-spatial resolution, this study aims to decipher the neural pathway responsible for discriminating low-arousal and high-arousal emotions. This study involves 19 patients with pharmacologically resistant epilepsy who participate in a delayed match/mismatch sample task designed to separately assess their ability to discriminate between low-arousal and high-arousal emotions. Three groups of 11 brain subregions, with dominant lateralization, compose a network, which is identified as responsible for discriminating arousal-dependent emotions. The connection of these subregions, leading by the left insula and right middle temporal gyrus, defines the pathways for discriminating emotions with different arousals. Further, the separated network patterns related to emotional discrimination are face-independent. Overall, the left insula and the right middle temporal gyrus emerge as core components in the network, which plays key roles in the dynamic course for discriminating low- and high-arousal emotions in the human brain.