EEG dynamics reveal a dissociation between storage and selective attention within working memory

Area of Science:

• Cognitive Neuroscience
• Psychology
• Neuroscience

Background:

• Selective attention is crucial for prioritizing information in working memory (WM), enhancing performance for attended items.
• The fate of unattended representations within WM, specifically whether they undergo information loss, remains an open question.
• Understanding the interplay between attention and storage is key to elucidating WM mechanisms.

Purpose of the Study:

• To test the hypothesis that selective attention and storage are independent mechanisms within working memory.
• To investigate whether unattended WM representations are subject to information loss.
• To examine how varying cue reliability influences attention allocation and information storage in WM.

Main Methods:

• Participants performed a working memory recall task while electroencephalography (EEG) was recorded.
• A retrospective cue was presented during the retention interval to indicate the likely item to be tested, with manipulated reliability.
• Contralateral delay activity (CDA) and contralateral alpha power suppression were used to measure storage and attention, respectively.

Main Results:

• Following highly reliable cues, attended items were prioritized, and non-cued items experienced information loss.
• With less reliable cues, unattended items were initially retained but later showed information loss, even when attention was reallocated.
• These findings indicate that storage and attention in WM are dissociable processes.

Conclusions:

• Selective attention and storage in working memory operate as distinct mechanisms.
• Information loss in unattended WM representations can occur, influenced by cue reliability and attention reallocation dynamics.
• The relative importance of representations dynamically modulates the interaction between attention and storage in working memory.