The results demonstrate that gray matter volume reductions in brain regions involved in processing socioemotional stimuli are associated with conduct disorder, regardless of age of onset. Brain structural abnormalities may contribute to the emergence of adolescent-onset as well as early-onset conduct disorder.

Individuals with Autism Spectrum Conditions (ASC) have difficulties in social interaction and communication, which is reflected in hypoactivation of brain regions engaged in social processing, such as medial prefrontal cortex (mPFC), amygdala and insula. Resting state studies in ASC have identified reduced connectivity of the default mode network (DMN), which includes mPFC, suggesting that other resting state networks incorporating ‘social’ brain regions may also be abnormal. Using Seed-based Connectivity and Group Independent Component Analysis (ICA) approaches, we looked at resting functional connectivity in ASC between specific ‘social’ brain regions, as well as within and between whole networks incorporating these regions. We found reduced functional connectivity within the DMN in individuals with ASC, using both ICA and seed-based approaches. Two further networks identified by ICA, the salience network, incorporating the insula and a medial temporal lobe network, incorporating the amygdala, showed reduced inter-network connectivity. This was underlined by reduced seed-based connectivity between the insula and amygdala. The results demonstrate significantly reduced functional connectivity within and between resting state networks incorporating ‘social’ brain regions. This reduced connectivity may result in difficulties in communication and integration of information across these networks, which could contribute to the impaired processing of social signals in ASC.

Eating is not only triggered by hunger but also by the sight of foods. Viewing appetizing foods alone can induce food craving and eating, although there is considerable variation in this "external food sensitivity" (EFS). Because increased EFS is associated with overeating, identifying its neural correlates is important for understanding the current epidemic of obesity. Animal research has identified the ventral striatum, amygdala, hypothalamus, medial prefrontal and premotor cortices as key interacting structures for feeding. However, it is unclear whether a similar network exists in humans and how it is affected by EFS. Using functional magnetic resonance imaging, we showed that viewing appetizing compared with bland foods produced changes in connectivity among the human ventral striatum, amygdala, anterior cingulate and premotor cortex that were strongly correlated with EFS. Differences in the dynamic interactions within the human appetitive network in response to pictures of appetizing foods may determine an individual's risk of obesity.

Behavioural impairment on complex emotion recognition associated with mental state attribution is a phenotypic, rather than an endophenotypic, marker of ASC. However, the neural response during the Eyes task is a potential endophenotypic marker for ASC, particularly in females.