Emotional Content Enhances Attentional Tracking of Conversations through Context-Sensitive Modulation of...

Engagement in conversation often requires continuous monitoring of relevant speech in a continuously evolving auditory environment. Emotional salience of semantic content may influence this process, but its role in attentional tracking of continuous speech remains unclear. We address this question using an audiovisual "Cocktail-party" paradigm combined with source-localized magnetoencephalography and encoding-decoding analyses. Participants (18 female, 14 male) selectively attended to one dialogue while ignoring a concurrent distractor dialogue, with both emotional salience and semantic coherence of the conversations manipulated independently. Decoding analyses revealed that negatively valenced, high-arousal, and socially relevant semantic content strengthened neural speech tracking, but only for attended dialogues. This effect depended on semantic structure, emerging earlier in semantically coherent than incoherent dialogues. Encoding analyses further showed latency- and region-specific effects across temporal, parietal, and frontal cortical regions. Emotional salience and coherence jointly modulated mid-latency (100 - 250 ms) responses, whereas late-latency (270 - 450 ms) responses were driven primarily by emotional salience. These findings demonstrate that emotional meaning enhances neural prioritization of attended speech and semantic coherence shapes the temporal dynamics of this enhancement. Together, these results indicate context-sensitive emotional modulation of auditory-language processing during selective listening of continuous speech.Significance Statement Understanding how the brain prioritizes and selectively processes information in naturalistic, continuously evolving audiovisual scenes such as conversations is a central challenge in neuroscience. Here, we show that conversations conveying negatively valenced, high-arousal, and socially relevant content enhance neural tracking of attended speech in a noisy cocktail-party setting. This enhanced tracking depends on the semantic structure of the conversation, emerging earlier for coherent dialogues that are easy to follow. Furthermore, we show that emotional content strengthens mechanisms related to speech comprehension and sharpens segregation of relevant from irrelevant talk. These findings demonstrate that emotional meaning and semantic continuity jointly shape cortical processing of continuous speech, providing new insight into how the brain selects and processes meaningful information during a conversation.