RESUMO
The involvement of left-behind children (LBC) in school bullying has raised concern in China. However, the susceptibility of LBC to engage in bullying is controversial, and comprehensive, representative studies covering the entire country are lacking. The purpose of this study was to evaluate the prevalence and severity of school bullying among LBC. The Chinese National Knowledge Network, WanFang, VIP, PubMed, Web of Science, EMBASE, and EBSCO databases were searched for literature on being left-behind and bullying before April 2022. The effect size was measured by odds ratio (ORs), standard mean difference (SMD), and 95% confidence interval (CI). Random-effects or fixed-effects models were selected for meta-analysis, and subgroup analysis was used to explore the sources of heterogeneity. The meta-analysis included 25 studies of school bullying among LBC and non-LBC (NLBC). The prevalence of bullying perpetration and victimization among LBC were 18.58% (95% CI [3.72%, 33.44%], p < .05) and 40.62% (95% CI [25.47%, 55.78%], p < .05), respectively. Compared with NLBC, the risk of bullying perpetration and victimization among LBC increased 1.97 times (OR = 1.97, 95% CI [1.77, 2.20], p < .05) and 2.17 times (OR = 2.17, 95% CI [1.43, 3.29], p < .05), respectively. The severity of bullying experienced by LBC was higher than that of NLBC (SMD = 0.49, 95% CI [0.20, 0.79], p < .05). The prevalence and severity of school bullying were higher in LBC than in NLBC, and left-behindness was positively associated with school bullying. LBC are a crucial population to protect when developing bullying interventions.
RESUMO
In everyday life, error monitoring and processing are important for improving ongoing performance in response to a changing environment. However, detecting an error is not always a conscious process. The temporal activation patterns of brain areas related to cognitive control in the absence of conscious awareness of an error remain unknown. In the present study, event-related potentials (ERPs) in the brain were used to explore the neural bases of unconscious error detection when subjects solved a Chinese anagram task. Our ERP data showed that the unconscious error detection (UED) response elicited a more negative ERP component (N2) than did no error (NE) and detect error (DE) responses in the 300-400-ms time window, and the DE elicited a greater late positive component (LPC) than did the UED and NE in the 900-1200-ms time window after the onset of the anagram stimuli. Taken together with the results of dipole source analysis, the N2 (anterior cingulate cortex) might reflect unconscious/automatic conflict monitoring, and the LPC (superior/medial frontal gyrus) might reflect conscious error recognition.
