Loss of precise auditory sampling as a sign of value-driven visual attentional capture

By linking with rewards, sensory signals gain salience and the ability to influence selective attention even when they have become irrelevant. The dynamics of reward-driven distraction in the brain remains unclear, particularly at the time of shaping multisensory associations. It is unknown whether reward-driven distraction by visual signals interferes with the robust ability of the brain to phase-lock to auditory modulations. In a dynamic audiovisual (AV) coherence task, we investigated how visual reward associations affect performance and modulate auditory encoding precision. Participants were presented with dual visual object streams flickering at different rates, accompanied by an amplitude-modulated sound matching one of the flicker periods, for subjects to identify the matching visual object. At the periphery, an irrelevant color feature flickers in sync with the target and may capture observers’ attention, due to a prior color-reward association training regime. Electroencephalography (EEG) recordings assessed participants’ sensitivity to the audiovisual task. The findings indicate that target discrimination was impoverished in the presence of colors that had previously been associated with reward. The phase locking of auditory responses also decreased, evidencing an attentional shift away from auditory modulation representations. Moreover, down-modulations of auditory phase locking predicted the effect size of participants’ reward-driven distraction. These findings highlight how value-driven attentional capture fundamentally alters multimodal processing in the temporal domain. They suggest that less precise neural representations of unisensory streams not connected to reward-associated cues undermine the processing of temporal coherence relationships between multisensory streams. Momentary inter-modal competition, induced by reward-driven distraction, appears consistent with the systematic exploit of gaps in active attentional sampling strategies that unfold over time.