Lui, Wai-KinWai-KinLui2025-12-032025-12-032025http://hdl.handle.net/20.500.11861/26259130 PagesAlthough the association between aggression and problematic pornography use (PPU) is documented, the association between trait aggression and online form of PPU, and the role of Sexual-Aggressive Fulfilment Pornography Use Expectancy (SAF) and trait self-control in the relationship are understudied. The present study examines the psychological mechanisms of trait aggression associated to problematic online adult pornography use (POAPU). Two waves of data collection were conducted to test the associations cross-sectionally and longitudinally. 1986 Chinese and 1396 US, and 861 Chinese and 628 US valid responses on online questionnaires were received from online crowdsourcing platforms in November 2023, and November 2024. The results of Part 1 study revealed that SAF mediates the relationship between trait aggression and POAPU, while trait self-control moderates the relationship between trait aggression and SAF. A stronger mediation effect of SAF and the negative mediation effect of T1 SAF in the second part among the Chinese sample underscore significant cross-country differences in the development of POAPU. Furthermore, the results of Part 2 study showed significant mediation effect of T2 SAF and moderation effect of T1 trait self-control on the relationship between T1 trait aggression and T2 SAF among Chinese sample, and on the relationship between T1 trait aggression and T2 POAPU among US sample, suggesting the cross-country difference on the buffering effect of trait self-control. These findings illuminate the importance of cross-country sensitivity in understanding the associations among trait aggression, trait self-control, SAF, and POAPU, and relevant implications are discussed.enThesis