Changes in paralimbic connectivity were the cornerstone of developing cortico-cortico connectivity. Paralimbic areas play a major role in detection of salient environmental events [71], in facilitating flexible behaviors in response to risk, reward, and punishment [72],[73], and in goal directed behavior [74]. Converging evidence from a number of brain imaging studies across several task domains suggests that the insula and the anterior cingulate cortex respond to the degree of subjective salience, whether cognitive, homeostatic, or emotional [75],[76]. These paralimbic areas play a causal role in activating attentional and memory systems within association areas to facilitate controlled processing of stimuli during cognitively demanding tasks [71]. Paralimbic and association areas also moderate emotional reactivity to stimuli in limbic areas [77],[78]. These core motivational and regulatory processes are known to undergo significant changes during adolescence [79], a time when coordinated interaction of emotion, reasoning, and decision-making becomes increasingly important [80],[81]. The tighter integration of paralimbic with association and limbic areas revealed by our study may underlie the large-scale functional changes that facilitate this critical developmental process.
