Neural response to aggressive and positive interactions in violent offenders and nonviolent individuals

Neural basis of reward expectancy inducing proactive aggression

Proactive aggression refers to deliberate and unprovoked behavior, typically motivated by personal gain or expected reward. Reward expectancy is generally recognized as a critical factor that may influence proactive aggression, but its neural mechanisms remain unknown. We conducted a task-based functional magnetic resonance imaging (fMRI) experiment to investigate the relationship between reward expectancy and proactive aggression. 37 participants (20 females, mean age = 20.8 ± 1.42, age range = 18-23 years) completed a reward-harm task. In the experiment, reward valence expectancy and reward possibility expectancy were manipulated respectively by varying amounts (low: 0.5-1.5 yuan; high: 10.5-11.5 yuan) and possibilities (low: 10%-30%; high: 70%-90%) of money that participants could obtain by choosing to aggress. Participants received fMRI scans throughout the experiment. Brain activation regions associated with reward expectancy mainly involve the middle frontal gyrus, lingual gyrus, inferior temporal gyrus, anterior cuneus, caudate nucleus, inferior frontal gyrus, cingulate gyrus, anterior central gyrus, and posterior central gyrus. Associations between brain activation and reward expectancy in the left insula, left middle frontal gyrus, left thalamus, and right middle frontal gyrus were found to be related to proactive aggression. Furthermore, the brain activation regions primarily involved in proactive aggression induced by reward expectancy were the insula, inferior frontal gyrus, inferior temporal gyrus, pallidum, and caudate nucleus. Under conditions of high reward expectancy, participants engage in more proactive aggressive behavior. Reward expectancy involves the activation of reward- and social-cognition-related brain regions, and these associations are instrumental in proactive aggressive decisions.

Mentalization-based treatment for adolescents with conduct disorder (MBT-CD): a feasibility study

Conduct disorder (CD) is a common psychiatric disorder in youth characterized by persisting norm-violating or aggressive behavior. Considering high individual and societal burden, feasible and effective psychotherapeutic treatment is desirable. Yet, treatments and research in this patient group are scarce. This study investigates the feasibility of mentalization-based treatment for adolescents with CD (MBT-CD) in terms of acceptability of MBT-CD and scientific assessments by participants as well as necessary organizational resources to conduct a consecutive randomized controlled trial (RCT). Recruitment, adherence and treatment session numbers were descriptively analyzed. Treatment evaluation interviews were qualitatively analyzed. A subset of sessions of therapists without prior MBT experience was rated for MBT adherence. Quantitative data were used to plan a consecutive RCT. Pre to post treatment changes in diagnosis and self-reported aggression, mentalizing and personality functioning were preliminarily analyzed. N = 45 adolescents with CD were recruited. 43% dropped out. Acceptance of scientific assessments was somewhat lower than therapy adherence (questionnaires filled out by ~ 80% of adolescents in treatment), and low at follow-up (25% of treatment completers). Mean session number was 30.3. Most treatment completers were satisfied with MBT-CD. Referrals mainly came from child and youth services and psychiatry. Nine of 16 sessions rated for MBT adherence were adherent. A priori sample size estimation for a prospective RCT with a drop-out rate of 43% yielded a sample of N = 158 to detect an effect f = .15 with 80% power in a repeated measures ANOVA. Pre-post analyses revealed diagnostic improvement in 68%. Of self-reported data, empathy pathology improved. Findings provide a sound basis for a consecutive feasibility and pilot RCT. TRIAL REGISTRATION: Clinicaltrials.gov, registration number NCT02988453, November 30, 2016, https://clinicaltrials.gov/ct2/show/NCT02988453.