RESUMO
Background: Psychosis is characterized by problems in social functioning and trust, the assumed glue to positive social relations. But what helps building trust? A prime candidate could be social mindfulness: the ability and willingness to see and consider another person's needs and wishes during social decision making. We investigated whether first-episode psychosis patients (FEP) and patients at clinical high-risk (CHR) show reduced social mindfulness, and examined the underlying neural mechanisms. Methods: Twenty FEP, 17 CHR and 46 healthy controls, aged 16-31, performed the social mindfulness task (SoMi) during fMRI scanning, spontaneously and after the instruction "to keep the other's best interest in mind." As first of two people, participants had to choose one out of four products, of which three were identical and one was unique, differing in a single aspect (e.g., color). Results: FEP tended to choose the unique item (unmindful choice) more often than controls. After instruction, all groups significantly increased the number of mindful choices compared to the spontaneous condition. FEP showed reduced activation of the caudate and medial prefrontal cortex (mPFC) during mindful, and of the anterior cingulate cortex (ACC), mPFC, and left dorsolateral prefrontal cortex (dlPFC) during unmindful decisions. CHR showed reduced activation of the ACC compared to controls. Discussion: FEP showed a trend toward more unmindful choices. A similar increase of mindful choices after instruction indicated the ability for social mindfulness when prompted. Results suggested reduced sensitivity to the rewarding aspects of social mindfulness in FEP, and reduced consideration for the other player. FEP (and CHR to a lesser extent) might perceive unmindful choices as less incongruent with the automatic mindful responses than controls. Reduced socially mindful behavior in FEP may hinder the building of trust and cooperative interactions.
RESUMO
Successful social relationships require a consideration of a partner's thoughts and intentions. This aspect of social life is captured in the social mindfulness paradigm (SoMi task), in which participants make decisions that either limit or preserve options for their interaction partner's subsequent choice. Here we investigated the neural correlates of spontaneous socially mindful and unmindful behaviours. Functional magnetic resonance data were acquired from 47 healthy adolescents and young adults (age 16-27) as they completed the SoMi task. Being faced with socially relevant choices was associated with activity in the medial prefrontal cortex, anterior cingulate, caudate, and insula, which is consistent with prior neuroeconomical research. Importantly, socially mindful choices were associated with activity in the right parietal cortex and the caudate, whereas unmindful choices were associated with activity in the left prefrontal cortex. These neural findings were consistent with the behavioural preference for mindful choices, suggesting that socially mindful decisions are the basic inclination, whereas socially unmindful responses may require greater effort and control. Together, these results begin to uncover the neural correlates of socially mindful and unmindful choices, and illuminate the psychological processes involved in cooperative social behaviour.
Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Comportamento Cooperativo , Atenção Plena , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Teoria da Mente/fisiologia , Adulto JovemRESUMO
Substance abuse and psychotic disorders have a high rate of comorbidity. Both disorders are associated with changes in the dopaminergic transmission in the mesocorticolimbic pathways of the brain. Since antipsychotic medications interact with the dopamine receptors in these pathways, these medications could affect craving for substances. In the current study, the effect of clozapine (n = 27, mean dosage 350 mg), risperidone (n = 54, mean dosage 3.46 mg) and olanzapine (n = 60, mean dosage 13.78 mg) on subjective craving for cannabis was compared in 123 patients with cannabis dependence and psychotic disorder. Patients treated with risperidone reported significantly more craving compared with patients treated with clozapine (Z = -3.19, p = .001) or olanzapine (Z = -2.24, p = .025). No significant differences in craving between clozapine and olanzapine were found. These results are in concordance with findings in the literature on this subject and could be explained by differences in three dopamine mediated mechanisms of these compounds: 1) occupancy rate of dopamine D(2) receptors, 2) dissociation rate of dopamine D(2) receptors, 3) D(1)/D(2) occupancy ratio. Risperidone and clozapine show a maximal difference in D(2) receptor occupancy rate, dissociation rate and D(1)/D(2) ratio. Olanzapine is intermediate between risperidone and clozapine in these characteristics.