Paying attention to speech: The role of working memory capacity and professional experience

Managing attention in multispeaker environments is a challenging feat that is critical for human performance. However, why some people are better than others in allocating attention appropriately remains highly unknown. Here, we investigated the contribution of two factors—working memory capacity (WMC) and professional experience—to performance on two different types of attention task: selective attention to one speaker and distributed attention among multiple concurrent speakers. We compared performance across three groups: individuals with low (n = 20) and high (n = 25) WMC, and aircraft pilots (n = 24), whose profession poses extremely high demands for both selective and distributed attention to speech. Results suggests that selective attention is highly effective, with good performance maintained under increasingly adverse conditions, whereas performance decreases substantially with the requirement to distribute attention among a larger number of speakers. Importantly, both types of attention benefit from higher WMC, suggesting reliance on some common capacity-limited resources. However, only selective attention was further improved in the pilots, pointing to its flexible and trainable nature, whereas distributed attention seems to suffer from more fixed and severe processing bottlenecks.