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The formation of a coherent and unified self-concept represents a key developmental stage during adolescence. Imaging studies on self-referential processing in adolescents are rare, and it is not clear whether neural structures involved in self-reflection are also involved in reflections of familiar others. In the current study, 41 adolescents were asked to make judgments about trait adjectives during functional magnetic resonance imaging (fMRI): they had to indicate whether the word describes themselves, their friends, their teachers or politicians. Findings indicate a greater overlap in neural networks for responses to self- and friend-related judgments compared to teachers and politicians. In particular, classic self-reference structures such as the ventromedial prefrontal cortex and medial posterior parietal cortex also exhibited higher activation to judgments about friends. In contrast, brain responses towards judgments of teachers (familiar others) compared to politicians (unfamiliar others) did not significantly differ. Results support behavioral findings of a greater relevance of friends for the development of a self-concept during adolescence and indicate underlying functional brain processes. Hum Brain Mapp 38:987-996, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Adolescence is a critical maturation period for human cognitive control and executive function. In this study, a large sample of adolescents (n = 85) performed a reversal learning task during functional magnetic resonance imaging. We analyzed behavioral data using a reinforcement learning model to provide individually fitted parameters and imaging data with regard to reward prediction errors (PE). Following a model-based approach, we formed two groups depending on whether individuals tended to update expectations predominantly for the chosen stimulus or also for the unchosen one. These groups significantly differed in their problem behavior score obtained using the child behavior checklist (CBCL) and in a measure of their developmental stage. Imaging results showed that dorsolateral striatal areas covaried with PE. Participants who relied less on learning based on task structure showed less prefrontal activation compared with participants who relied more on task structure. An exploratory analysis revealed that PE-related activity was associated with pubertal development in prefrontal areas, insula and anterior cingulate. These findings support the hypothesis that the prefrontal cortex is implicated in mediating flexible goal-directed behavioral control., (© 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

The perception of control over the environment constitutes a fundamental biological adaptive mechanism, especially during development. Previous studies comparing an active choice condition with a passive no-choice condition showed that the neural basis of this mechanism is associated with increased activity within the striatum and the prefrontal cortex. In the current study, we aimed to investigate whether subjective belief of control in an uncertain gambling situation induces elevated activation in a cortico-striatal network. We investigated 79 adolescents (age range: 13-16years) during reward anticipation with a slot machine task using functional magnetic resonance imaging. We assessed post-experimentally whether the participants experienced a subjective illusion of control on winning or losing in this task that was objectively not given. Nineteen adolescents experienced an illusion of control during slot machine gambling. This illusion of control group showed an increased neural activity during reward anticipation within a cortico-striatal network including ventral striatum (VS) as well as right inferior frontal gyrus (rIFG) relative to the group reporting no illusion of control. The rIFG activity was inversely associated with impulsivity in the no illusion of control group. The subjective belief about control led to an elevated ventral striatal activity, which is known to be involved in the processing of reward. This finding strengthens the notion that subjectively perceived control, not necessarily the objective presence of control, affects striatal reward-related processing., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Processing of reward is the basis of adaptive behavior of the human being. Neural correlates of reward processing seem to be influenced by developmental changes from adolescence to late adulthood. The aim of this study is to uncover these neural correlates during a slot machine gambling task across the lifespan. Therefore, we used functional magnetic resonance imaging to investigate 102 volunteers in three different age groups: 34 adolescents, 34 younger adults, and 34 older adults. We focused on the core reward areas ventral striatum (VS) and ventromedial prefrontal cortex (VMPFC), the valence processing associated areas, anterior cingulate cortex (ACC) and insula, as well as information integration associated areas, dorsolateral prefrontal cortex (DLPFC), and inferior parietal lobule (IPL). Results showed that VS and VMPFC were characterized by a hyperactivation in adolescents compared with younger adults. Furthermore, the ACC and insula were characterized by a U-shape pattern (hypoactivation in younger adults compared with adolescents and older adults), whereas the DLPFC and IPL were characterized by a J-shaped form (hyperactivation in older adults compared with younger groups). Furthermore, a functional connectivity analysis revealed an elevated negative functional coupling between the inhibition-related area rIFG and VS in younger adults compared with adolescents. Results indicate that lifespan-related changes during reward anticipation are characterized by different trajectories in different reward network modules and support the hypothesis of an imbalance in maturation of striatal and prefrontal cortex in adolescents. Furthermore, these results suggest compensatory age-specific effects in fronto-parietal regions., (Copyright © 2014 Wiley Periodicals, Inc.)