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Attributions are constantly assigned in everyday life. A well-known phenomenon is the self-serving bias: that is, people's tendency to attribute positive events to internal causes (themselves) and negative events to external causes (other persons/circumstances). Here, we investigated the neural correlates of the cognitive processes implicated in self-serving attributions using social situations that differed in their emotional saliences. We administered an attributional bias task during fMRI scanning in a large sample of healthy subjects (n = 71). Eighty sentences describing positive or negative social situations were presented, and subjects decided via buttonpress whether the situation had been caused by themselves or by the other person involved. Comparing positive with negative sentences revealed activations of the bilateral posterior cingulate cortex (PCC). Self-attribution correlated with activation of the posterior portion of the precuneus. However, self-attributed positive versus negative sentences showed activation of the anterior portion of the precuneus, and self-attributed negative versus positive sentences demonstrated activation of the bilateral insular cortex. All significant activations were reported with a statistical threshold of p ≤ .001, uncorrected. In addition, a comparison of our fMRI task with data from the Internal, Personal and Situational Attributions Questionnaire, Revised German Version, demonstrated convergent validity. Our findings suggest that the precuneus and the PCC are involved in the evaluation of social events with particular regional specificities: The PCC is activated during emotional evaluation, the posterior precuneus during attributional evaluation, and the anterior precuneus during self-serving processes. Furthermore, we assume that insula activation is a correlate of awareness of personal agency in negative situations.

Emotion discrimination deficits represent a well-established finding in schizophrenia. Although imaging studies addressed the cerebral dysfunctions underlying emotion perception in adult patients, the question of trait vs state characteristics is still unresolved. The investigation of juvenile patients offers the advantage of studying schizophrenia at an age where influences of illness course and long-term medication are minimized. This may enable a more detailed characterization of emotion discrimination impairments and their cerebral correlates with respect to their appearance and exact nature. A total of 12 juvenile patients with early onset schizophrenia and matched healthy juveniles participated in this study. fMRI data were acquired during an emotion discrimination task consisting of standardized photographs of faces displaying happy, sad, angry, fearful, or neutral facial expression. Similar to findings in adult patients, juvenile patients exhibited reduced performance specificity whereas sensitivity was unaffected. Independent of the valence, their processing of emotional faces was associated with hypoactivations in both fusiform gyri and in the left inferior occipital gyrus. In addition, hyperactivations in patients were found in the right cuneus common to happy, angry, and fearful faces. Further, most distinct changes were present in juvenile patients when processing sad faces. These results point to a dysfunction in cerebral circuits relevant for emotion processing already prominent in adolescent schizophrenia patients. Regions affected by a decrease in activation are related to visual and face processing, similar to deficits reported in adult patients. These changes are accompanied by hyperactivations in areas related to emotion regulation and attribution, possibly reflecting compensatory mechanisms.

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Self-concept is deeply affected in schizophrenia. Positive symptoms in particular are related to disturbed self/other distinctions. The neural networks underlying self-evaluation in schizophrenia have barely been investigated. The study reported here involved 13 patients with schizophrenia and 13 matched controls. During functional MRI, participants decided in three conditions whether the presented positive and negative personality traits characterized themselves, an intimate person, or included a certain letter. Based on the responses, each experimental condition was designed using a flexible factorial model. Controls and patients showed a similar behavioral pattern during self-evaluation, with group comparison revealing decreased activation in patients in the left inferior temporal gyrus and both temporal poles during self-ascription of traits, and in the anterior medial prefrontal cortex during evaluation of an intimate person. In patients, positive symptoms correlated positively with brain activation in the left parahippocampus during trait self-ascription. Hence, while evaluating themselves, schizophrenia patients revealed decreased activation in areas related to self-awareness overlapping with networks involved in theory of mind, empathy and social knowledge. Moreover, patients' brain activation during self-reflection was affected by the current positive symptomatology. The close interaction between self and other highlights the clinical and social relevance of self-processing deficits in schizophrenia.

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