Longitudinal Changes Of Amygdala Functional Connectivity In Adolescents Prenatally Exposed To Cocaine

Prenatal cocaine exposure(PCE)is associated with long-term effect of arousal dysregulation,but interactions between the exposure and neurodevelopment have rarely been investigated directly with longitudinal study designs.To shed more light on this research area,our previous study had focused on task-elicited emotional arousal and noted a persistently high amygdala activation in the development of adolescents with PCE.However,while externally imposed emotional arousal could be considered as a “state” effect depending on specific task stimuli,it is still unclear whether similar developmental alterations extend into intrinsic functional connectivity(FC),possibly reflecting more of a “trait” effect.To answer this question,the present study took a longitudinal design and analyzed resting-state functional magnetic resonance imaging(rfMRI)data acquired twice from 41 adolescents(25 with PCE and 16 non-exposed controls)at their mean ages of 14.3 and 16.6,respectively.Seeding in bilateral amygdalae and comparing the 2nd scan with the 1st,we examined the interaction effect between PCE and age on FCs in the emotional network.Compared with the younger age,we observed a generally decreased FC in the emotional network of the control group at the older age;but these FCs were generally increased at the older age in this same network of the PCE group.Additionally,this interaction effect of exposure by age in the right fusiform was positively correlated with the emotional interference imposed by external stimuli in the task state.Adolescents with prenatal cocaine exposure largely exhibit an opposite age dependence with their non-exposed peers for amygdala functional connectivity.This observation in resting state appears in parallel with developmental group differences in task state.In the emotion network anchored in bilateral amygdala,task-state activation and resting-state functional connectivity may represent state and trait alterations,respectively;and jointly contribute into the long-term teratogenic effect of arousal dysregulation in adolescents with PCE.These results provided additional data directly characterizing developmental changes in the emotional network of adolescents prenatally exposed to cocaine,complementing and extending the notion of a PCE associated long-term teratogenic effect on arousal regulation.