Abstract
Although working memory is generally considered a highly dynamic mnemonic store, popular laboratory tasks used to understand its psychological and neural mechanisms (such as change detection and continuous reproduction) often remain relatively “static,” involving the retention of a set number of items throughout a shared delay interval. In the current study, we investigated visual working memory in a more dynamic setting, and assessed the following: (1) whether internally guided temporal expectations can dynamically and reversibly prioritize individual mnemonic items at specific times at which they are deemed most relevant; and (2) the neural substrates that support such dynamic prioritization. Participants encoded two differently colored oriented bars into visual working memory to retrieve the orientation of one bar with a precision judgment when subsequently probed. To test for the flexible temporal control to access and retrieve remembered items, we manipulated the probability for each of the two bars to be probed over time, and recorded EEG in healthy human volunteers. Temporal expectations had a profound influence on working memory performance, leading to faster access times as well as more accurate orientation reproductions for items that were probed at expected times. Furthermore, this dynamic prioritization was associated with the temporally specific attenuation of contralateral α (8-14 Hz) oscillations that, moreover, predicted working memory access times on a trial-by-trial basis. We conclude that attentional prioritization in working memory can be dynamically steered by internally guided temporal expectations, and is supported by the attenuation of α oscillations in task-relevant sensory brain areas.
Original language | English |
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Pages (from-to) | 437-445 |
Number of pages | 9 |
Journal | The Journal of Neuroscience |
Volume | 37 |
Issue number | 2 |
DOIs | |
Publication status | Published - 11 Jan 2017 |
Externally published | Yes |
Funding
Received July 18, 2016; revised Sept. 8, 2016; accepted Sept. 16, 2016. Author contributions: F.v.E., M.N., and A.C.N. designed research; F.v.E. and M.N. performed research; F.v.E. analyzed data; F.v.E., M.N., and A.C.N. wrote the paper. This work was supported by Royal Society and British Academy Newton International Fellowship NF140330 to F.v.E.,SwissNationalScienceFoundationGrantP1ZHP1161985toM.N.,WellcomeTrustSeniorInvestigatorAward 104571/Z/14/ZtoA.C.N.,andtheNationalInstituteforHealthResearchOxfordBiomedicalResearchCentrebasedat Oxford University Hospitals Trust Oxford University. We thank Sammi Chekroud and Nick Myers for input on the experimental design and assistance during data collection and analysis. The authors declare no competing financial interests. This article is freely available online through the J Neurosci Author Open Choice option. Correspondence should be addressed to Dr. Freek van Ede, Oxford Centre for Human Brain Activity, Department of Psychiatry,UniversityofOxford,WarnefordHospital,OX37JX,Oxford,UK.E-mail:[email protected].
Funders | Funder number |
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British Academy Newton International | NF140330 |
Royal Society |
Keywords
- Attention
- Neuronal oscillations
- Temporal attention
- Working memory
- α scillations