Shuxiang Hu ^* Ying Liu Qizong Yue Huan Zhao Maoping Zheng ^*

• School of Music, Southwest University, Chongqing, China

Nostalgia is a complex emotional experience involving fond memories of the past and mild sadness, which is characterized by positive emotions associated with reflecting on the past. Nostalgia can awaken the emotional memories of loved ones or of events, contributing to an increase in positive emotions. An unresolved question regarding nostalgia is whether different channels of nostalgia input exhibit different mechanisms. Therefore, this study examined the emotional and neural effects of nostalgia using various sensory channels through behavioral experiments and electroencephalography measurements conducted with college students in China. Participants' emotions were elicited using nostalgic and non-nostalgic stimuli presented through three different sensory channels: auditory (sound only), visual (e.g., still images or synchronized lyrics related to music), and audiovisual (a combination of sound and visual elements, such as music videos). The results demonstrated that nostalgic stimuli elicited significantly higher levels of emotional arousal, pleasure, nostalgia, and dominance compared to non-nostalgic stimuli. At the neural level, the results revealed that nostalgic stimuli were favorable to enhancing the connection strength , global and local efficiency, and diminished eigenpath length of brain networks in the alpha and gamma bands. Moreover, nostalgia through the auditory channel induced higher activity intensity (the theta and gamma bands) and brainwave amplitudes (the alpha bands). In addition, the audiovisual channel was capable of triggering stronger alpha-wave responses than the visual channel alone. These findings suggest that nostalgia can effectively trigger positive emotional states and enhance cognitive processing, and the audiovisual showed advantages in alpha-wave response. Further research is needed to explore the potential of nostalgia as an adjunctive therapeutic tool.