Keep bright in the dark: Multimodal emotional effects on donation-based crowdfunding performance and their empathic mechanisms.

How to raise donations effectively, especially in the E-era, has puzzled fundraisers and scientists across various disciplines. Our research focuses on donation-based crowdfunding projects and investigates how the emotional valence expressed verbally (in textual descriptions) and visually (in facial images) in project descriptions affects project performance. Study 1 uses field data (N = 3817), grabs project information and descriptions from a top donation-based crowdfunding platform, computes visual and verbal emotional valence using a deep-learning-based affective computing method and analyses how multimodal emotional valence influences donation outcomes. Study 2 conducts experiments in GPT-4 (Study 2a, N = 400) and humans (Study 2b, N = 240), manipulates the project's visual and verbal emotional valence through AI-generated stimuli and then assesses donation decisions (both GPT-4 and humans) and corresponding state empathy (humans). The results indicate a multimodal positivity superiority effect: both visual and verbal emotional valence promote initial whether-to-donate decisions, whereas only verbal emotional valence further promotes the how-much-to-donate decisions. Notably, such multimodal emotional effects can be explained through different mediating paths of empathic concern and empathic hopefulness. The current study theoretically facilitates our understanding of the emotional motivations underlying human prosociality and provides insights into crafting impactful advertisements for online donations.