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Gradient mapping is an important technique to summarize high dimensional biological features as low dimensional manifold representations in exploring brain structure-function relationships at various levels of the cerebral cortex. While recent studies have characterized the major gradients of functional connectivity in several brain structures using this technique, very few have systematically examined the correspondence of such gradients across structures under a common systems-level framework. Using resting-state functional magnetic resonance imaging, here we show that the organizing principles of the isocortex, and those of the cerebellum and hippocampus in relation to the isocortex, can be described using two common functional gradients. We suggest that the similarity in functional connectivity gradients across these structures can be meaningfully interpreted within a common computational framework based on the principles of predictive processing. The present results, and the specific hypotheses that they suggest, represent an important step toward an integrative account of brain function. Analysis of functional MRI data from the Human Connectome Project and Brain Genomics Superstruct Project reveals common functional gradients among the human isocortex, cerebellum, and hippocampus. [ABSTRACT FROM AUTHOR]

Emotional well-being depends on the ability to adaptively cope with various emotional challenges. Most studies have investigated the neural mechanisms of emotion regulation strategies deployed relatively later in the timing of processing that leads to full emotional experiences. However, less is known about strategies that are engaged in earlier stages of emotion processing, such as those involving attentional deployment. We investigated the neural mechanisms associated with self-guided Focused Attention (FA) in mitigating subjective negative emotional experiences. Functional magnetic resonance imaging (fMRI) data were recorded while participants viewed a series of composite negative and neutral images with distinguishable foreground (FG) and background (BG) areas. Participants were instructed to focus either on the FG or BG components of the images, and then rated their emotional experiences. Behavioral results showed that FA was successful in decreasing emotional ratings for negative images viewed in BG Focus condition. At the neural level, the BG Focus was associated with increased activity in regions typically implicated in top-down executive control (dorsolateral prefrontal cortex and lateral parietal cortex) and decreased activity in regions linked to affective processing (amygdala and ventrolateral prefrontal cortex). Dissociable brain activity linked to FA also was identified in visual cortices, including between the parahippocampal and fusiform gyri, showing increased versus decreased activity, respectively, during the BG Focus. These findings complement the evidence from prior FA studies with recollected emotional memories as internal stimuli and further demonstrate the effectiveness of self-guided FA in mitigating negative emotional experiences associated with processing of external unpleasant stimuli. [ABSTRACT FROM AUTHOR]

Despite previous evidence identifying the role of ethnic and gender differences in nonverbal communication, few studies have comprehensively investigated the role of these factors in the effect of handshake on appraisals of social interactions. Here, 88 young adults (with equal proportions of Caucasians and East Asians, and women and men) observed and evaluated a series of movies illustrating guest-host interactions in a business setting. Each interaction started with a greeting protocol initiated by the host, which, in half of the trials, involved a handshake. The greeting was followed by a display of behaviors either encouraging (approach) or discouraging (avoidance) further interaction. Ethnicity and gender of the hosts were manipulated to depict the same categories represented by participants. First, the effect of handshake on appraisals of social interactions was more positive in Caucasian than in East Asian participants. Second, the effect of handshake on appraisals of social interactions was more positive for male than for female hosts in male participants, whereas such differences were not observed in female participants. Third, appraisals of social interactions involving approach and avoidance behaviors were more positive in Caucasian than in East Asian participants. Finally, appraisals of social interactions involving approach behaviors were more positive in female than in male participants. Overall, these findings shed light on the role of ethnic and gender differences in the appraisal of nonverbal behaviors, and extend our understanding of factors that may lead to successful social interaction in the context of growing diversity in our society. [ABSTRACT FROM AUTHOR]

The intrinsic functional architecture of the brain supports moment-to-moment maintenance of an internal model of the world. We hypothesized and found three interdependent architectural gradients underlying the organization of intrinsic functional connectivity within the human cerebral cortex. We used resting state fMRI data from two samples of healthy young adults (N's = 280 and 270) to generate functional connectivity maps of 109 seeds culled from published research, estimated their pairwise similarities, and multidimensionally scaled the resulting similarity matrix. We discovered an optimal three-dimensional solution, accounting for 98% of the variance within the similarity matrix. The three dimensions corresponded to three gradients, which spatially correlate with two functional features (external vs. internal sources of information; content representation vs. attentional modulation) and one structural feature (anatomically central vs. peripheral) of the brain. Remapping the three dimensions into coordinate space revealed that the connectivity maps were organized in a circumplex structure, indicating that the organization of intrinsic connectivity is jointly guided by graded changes along all three dimensions. Our findings emphasize coordination between multiple, continuous functional and anatomical gradients, and are consistent with the emerging predictive coding perspective. [ABSTRACT FROM AUTHOR]