The relationship between abnormalities in amygdala functional connectivity and emotion regulation difficulties in problematic smartphone users

Problematic Smartphone Use (PSU) refers to behaviors that are detrimental to a user's physical and mental health due to poor cell phone usage. Established resting-state functional magnetic resonance (fMRI) studies have shown that changes in the strength of connectivity between the amygdala and regulatory networks such as the precuneus and cerebellum are strongly associated with emotional impulsivity in a variety of addictive behaviors. However, there is still a lack of systematic empirical research on the specific patterns of altered functional connectivity of the amygdala network for the PSU population, and the relationship between such abnormalities and emotional regulation difficulties. In the present study, we compared the differences in amygdala functional networks between problematic cell phone users (PSU group, N = 37) and healthy controls (HC group, N = 35) through seed-point functional connectivity analyses, and further explored the associations between these connectivity changes and difficulties in emotion regulation (DERS) and the degree of cell phone dependence (SABAS). We performed functional connectivity analyses using the left and right amygdala as seed points, respectively, and identified significant functional connectivity values with GRF correction. The connectivity strength of each significant value was subsequently extracted and correlation analysis was used to assess its statistical association with DERS and SABAS scores. The results showed that in functional connectivity centered on the right amygdala network, compared to the HC group, the PSU group had significantly stronger connectivity in the right temporal pole and significantly weaker connectivity in the right thalamus, left precuneus, and left cerebellum. In the results of functional connectivity centered on the left amygdala network, the PSU group had enhanced connectivity in the left rolandic operculum, right postcentral gyrus, right inferior frontal gyrus, and left parietal lobule brain regions, and weaker connectivity in the left cerebellar brain regions. Correlation analysis showed that the left amygdala network was significantly negatively correlated with the connectivity values and SABAS scores of the left cerebellum, significantly positively correlated with the connectivity values and DERS scores of the right inferior frontal gyrus, significantly positively correlated with the connectivity values and SABAS and DERS scores of the left post-central gyrus, and significantly positively correlated with the connectivity values and DERS scores of the left superior parietal lobule. The right amygdala network was significantly negatively correlated with connectivity values and SABAS scores in the left cerebellum, left precuneus, and right thalamus. This exploratory study employed seed-based functional connectivity analysis centered on the bilateral amygdala to examine alterations in emotion-regulation networks in individuals with PSU and to preliminarily explore their associations with SABAS and DERS. Within the limitations of a modest sample size and a cross-sectional design, the results revealed group differences in emotion-related functional connectivity, providing preliminary evidence for the potential neural mechanisms underlying PSU.