The influence of being left behind on fear acquisition and academic performance-a study of left-behind children

Left-behind children (LBC) are defined as children (< 18 years old) whose parent(s) (one or both) migrate to work for at least six months per year. Separation from parents has been shown to negatively influence fear acquisition and academic performance. However, it remains unclear whether LBC exhibit impaired fear acquisition, and if so, whether it is associated with poor academic performance. This study recruited 72 children (LBC and non-LBC [NLBC]) using Pavlovian conditioned fear acquisition and generalization. In this task, the conditioned stimuli (CS+ or CS-) are two neutral female faces, and the unconditioned stimulus (US) is white noise. The second phase of the study included a generalization stimulus (GS), which was a 20% blend of the CS +/- faces. US expectancy was used to indicate fear learning. Differences between groups were analyzed separately for each phase (acquisition or generalization) using a linear mixed model with the Group, CS-type, and Trial as factors. Relationships between fear acquisition and (i) the duration of parental absence and (ii) academic performance were analyzed based on Pearson correlations. Academic performance was evaluated from each child's most recent final examination. The results showed that the NLBC group gradually learned to associate the CS+ with the US and to disassociate the CS- from the US during fear-acquisition trials; however, the LBC group did not. The degree of fear acquisition was negatively correlated with the duration of parental absence and positively correlated with current levels of academic performance. Thus, the results indicate that children who were separated from their parents in early childhood tend to (i) lack the ability to discriminate safety from threats and (ii) exhibit poor academic performance.