An fMRI study of inhibitory control and the effects of exposure to violence in Latin-American early adolescents: alterations in frontoparietal activation and performance

Abstract

We used functional magnetic resonance to investigate the effects of exposure to violence on early adolescent brain function in an inhibitory control task. We investigated the association among scores on self-reported exposure to violence, performance and brain activation. Thirty-seven early adolescents (ages 10-14) from a Latin-American urban region participated in the study. Results showed that recent and chronic exposure to violence was associated with less activation of a network of frontal regions, including the anterior cingulate gyrus and the superior frontal cortex; recent exposure to violence was also associated with less activation of the superior parietal lobe. Results also showed that less activation correlated with more prominent deterioration in the performance in the inhibitory control task (increased latency with time). The findings suggest that early adolescence exposure to violence is associated with differences in activation of a neural network commonly associated with executive function and control. The results underscore the urgency of addressing exposure to violence in adolescence, a period of high susceptibility to the environment, and are discussed in the light of the evidence of the effects of violence on adolescent brain function. Executive function training may be a candidate for targeted cognitive interventions aimed at mitigating these effects.

Keywords: adolescence; anterior cingulate cortex; frontoparietal network; inhibitory Control; violence.

Fig. 1

Negative correlation among JVQ-R2 Lifetime and Last Year scores with activation for all conditions (Go and Change) in the Change task. Clusters significant at p < 0.05 corrected for multiple comparisons (equivalent to a 71-voxel threshold and p < 0.005). (A) Sagittal slice showing anterior and middle cingulate cluster of negative correlation with Lifetime scores (crosshair at x = −6, y = 3, z = 35). (B) Sagittal slice showing anterior cingulate and posterior parietal clusters of negative correlation with Last Year scores (crosshair at x = −6, y = 19, z = 35). (C) Overlap among anterior cingulate negative correlation with Lifetime and Last Year exposure to violence: yellow-colored voxels represent the overlapping areas. AFNI (Cox, 1996).

Fig. 2

Association among increase in latency in response times with time and less activation for the clusters of negative correlation with exposure to violence. Participants who reported more exposure also showed more prominent deterioration in response times as the experiment progressed. (A) Dispersion plot for the betas for each participant’s activation for the anterior cingulate cluster (in association with JVQ-R2 Lifetime scores) and the slope of the latency in response times for each participant. (B) Dispersion plot for the betas for each participant’s activation for the anterior cingulate cluster (in association with JVQ-R2 Last Year scores) and the slope of the latency in response times for each participant. (C) Dispersion plot for the betas for each participant’s activation for the posterior parietal cluster (in association with JVQ-R2 Lifetime scores) and the slope of the latency in response times for each participant. Betas were extracted for the entire clusters. Latency represents the increase in latency during the experiment. AFNI (Cox, 1996).