Background
Deficits of reward sensitivity has been proposed as a key mechanism underlying both non-suicidal self-injury (NSSI) and depressive symptoms. However, the complex interplays between NSSI, depressive symptoms, and different components of reward sensitivity remain inadequately understood.
​​​​​​​
Methods
Network analysis was utilized to examine the inter-relationship patterns between NSSI, depressive symptoms (both total and item scores), reward sensitivity, and associated risk factors (e.g. emotion regulation strategies and childhood trauma) in a sample of Chinese college students (n = 5190). Network Comparison Tests were conducted to explore differences across three groups, including individuals with high depressive symptoms with a history of NSSI, individuals with high depressive symptoms without NSSI, and individuals with low depressive symptoms without NSSI.

Results:
In the networks for the entire sample, NSSI was indirectly linked to specific components of reward sensitivity, suggesting that theses associations may be explained by their shared connections with depressive symptoms, emotion regulation difficulties, and childhood trauma. ‘Reward responsiveness’ and ‘emotional abuse’ were the most central nodes. Network Comparison Tests revealed significant differences in network structure across groups. Specifically, ‘behavioral inhibition system’ was the most important node in the high-depressive subgroup with NSSI, while ‘reward responsiveness’ was the most central node in the high-depressive subgroup without NSSI.

Conclusion:
Our findings highlight the important role of reward sensitivity in NSSI and depressive symptoms, and provide specific targets for future research and potential intervention development among depressive individuals with and without a history of NSSI.