Responses to academic stress mediate the association between sleep difficulties and depressive/anxiety symptoms in Chinese adolescents.

OBJECTIVE: Sleep difficulties are pervasive in Chinese adolescents, which exert aversive influence on their emotional health. However, the underlying mechanisms of this effect remain unclear. This study addressed whether stress responses mediate the concurrent and prospective relationship between sleep difficulties and depressive/anxiety symptoms in Chinese adolescents. METHOD: 17,946 adolescents (14-18 years-old) were administrated the Pittsburgh Sleep Quality Index, the Center for Epidemiologic Studies Depression Scale, Revised Children's Manifest Anxiety Scale and the Responses to Stress Questionnaire. Further, 710 of them finished the one-year follow-up assessments. Structural equation models were conducted to determine the concurrent and prospective mediation effects of stress responses and the moderated effect of gender and age. RESULTS: Involuntary engagement and disengagement responses, as well as engagement coping, significantly mediated the cross-sectional relationship between sleep difficulties and depressive/anxiety symptoms. Moreover, sleep difficulties at baseline predicted enhanced involuntary engagement responses but reduced the use of engagement coping strategies one year later, resulting in an elevated level of depressive/anxiety symptoms. Finally, females and younger adolescents with greater sleep difficulties were more likely to generate maladaptive stress responses. LIMITATIONS: First, sleep difficulties were only measured using self-reported approaches. Second, potential confounding variables (e.g., socioeconomic status) were not adjusted for. Third, our study only focused on typically-developing youth samples rather than clinical samples. CONCLUSIONS: Our findings highlight the important role of stress responses in the relationship between sleep difficulties and depressive/anxiety symptoms. The findings might also shed some light on the psychological intervention of sleep difficulties and mood disorder in adolescent populations.

Developmental Trajectories of Attention in Typically Developing Chinese Children: A Four-Wave Longitudinal Study.

We conducted a 4-year longitudinal study to investigate trajectories of attention in a sample of 145 Chinese children. The Test of Everyday Attention was administered and latent growth modeling was used to capture developmental trajectories. We found that children's selective attention showed a linear increase, whereas attentional control and sustained attention increased rapidly then slowed down over 4 years. There was no significant correlation between the slopes of growth model for any subsystems. Girls showed higher initial levels of selective attention than boys, but no difference in growth rate. These findings support different developmental patterns in the attention network systems.

Multivariate Neural Representations of Value during Reward Anticipation and Consummation in the Human Orbitofrontal Cortex.

The role of the orbitofrontal cortex (OFC) in value processing is a focus of research. Conventional imaging analysis, where smoothing and averaging are employed, may not be sufficiently sensitive in studying the OFC, which has heterogeneous anatomical structures and functions. In this study, we employed representational similarity analysis (RSA) to reveal the multi-voxel fMRI patterns in the OFC associated with value processing during the anticipatory and the consummatory phases. We found that multi-voxel activation patterns in the OFC encoded magnitude and partial valence information (win vs. loss) but not outcome (favourable vs. unfavourable) during reward consummation. Furthermore, the lateral OFC rather than the medial OFC encoded loss information. Also, we found that OFC encoded values in a similar way to the ventral striatum (VS) or the anterior insula (AI) during reward anticipation regardless of motivated response and to the medial prefrontal cortex (MPFC) and the VS in reward consummation. In contrast, univariate analysis did not show changes of activation in the OFC. These findings suggest an important role of the OFC in value processing during reward anticipation and consummation.

Differential mesolimbic and prefrontal alterations during reward anticipation and consummation in positive and negative schizotypy.

Schizotypy is associated with anhedonia. However, previous findings on the neural substrates of anhedonia in schizotypy are mixed. In the present study, we measured the neural substrates associated with reward anticipation and consummation in positive and negative schizotypy using functional MRI. The Monetary Incentive Delay task was administered to 33 individuals with schizotypy (18 positive schizotypy (PS),15 negative schizotypy (NS)) and 22 healthy controls. Comparison between schizotypy individuals and controls were performed using two-sample T tests for contrast images involving gain versus non-gain anticipation condition and gain versus non-gain consummation condition. Multiple comparisons were corrected using Monte Carlo Simulation correction of p<.05. The results showed no significant difference in brain activity between controls and schizotypy individuals as a whole during gain anticipation or consummation. However, during the consummatory phase, NS individuals rather than PS individuals showed diminished left amygdala and left putamen activity compared with controls. We observed significantly weaker activation at the left ventral striatum during gain anticipation in NS individuals compared with controls. PS individuals, however, exhibited enhanced right ventral lateral prefrontal activity. These findings suggest that different dimensions of schizotypy may be underlied by different neural dysfunctions in reward anticipation and consummation.

Latent factor structure of the Das-Naglieri Cognitive Assessment System: a confirmatory factor analysis in a Chinese setting.

This study aims to measure the psychometric properties of the Das-Naglieri Cognitive Assessment System (D-N CAS) and to determine its clinical utility in a Chinese context. Confirmatory factor analysis (CFA) was conducted to examine the construct validity of the Chinese version of the D-N CAS among a group of 567, normally developed children. Test-retest reliability was examined in a random subsample of 30 children at a five-week interval. The clinical discrimination of the D-N CAS was also examined by comparing children with and without ADHD (18 children in each group) and by comparing children with and without Chinese reading disabilities (18 children in each group). The current Chinese sample demonstrated a four-factor solution for cognitive performance among children with normal development: Planning, Attention, Simultaneous processing and Successive processing (χ2(48)=91.90, p=.000; χ2/df=1.92, RMSEA=.050, GFI=.966, CFI=.954). Moreover, all subtests of the battery demonstrated acceptable test-retest reliability (r=.72-.90, p<.01) at a five-week interval among the subjects of the small subsample. Children with ADHD performed significantly worse than normal children on the Attention factor (p<.001) and the Planning factor (p<.05) of the D-N CAS, and children with Chinese reading disabilities performed significantly worse than normal children on the Simultaneous processing factor (p<.01), the Successive processing factor (p<.001) and the Planning factor (p<.05) of the D-N CAS. These findings suggested that the current four-factor structure of the D-N CAS was similar to the original factor structure of the test. The latent factor of the D-N CAS was fairly stable across the cultures. Moreover, the D-N CAS can distinguish between children with ADHD or Chinese reading disabilities and normally developed children.