Initially encoding attended but outdated information into working memory: behavioral and neural evidence

Abstract

Attention has traditionally been regarded as a gateway to working memory, largely determining whether information enters it. Recent work suggests that the brain actively inhibits attended but outdated information to prevent it from entering working memory. However, it remains unknown whether this information is blocked directly by attention before entering working memory, or after being encoded into working memory, given that such information has already been attended to and processed. This study explored this question by manipulating stimulus onset asynchronies (SOAs) in three experiments, including behavioral and electroencephalography (EEG) measures, and examining memory traces of attended but outdated information at different time points. Behavioral evidence demonstrated the stability of the memory trace of the attended but outdated information only when SOA was short. This finding was observed across different features and paradigms. Time-frequency analysis indicated that the brain inhibited attention to information matching the attended but outdated information in the early stage, with behavioral performance predicted by alpha modulation of the right hemisphere. These results suggest that attended but outdated information is initially encoded into working memory, even though it does not need to be remembered. These findings enhance our understanding of the impact of attention on working memory.