Multivariate patterns and long‐range temporal correlations of alpha oscillations are associated with flexible manipulation of visual working memory representations

• Published in: The European journal of neuroscience 2021-11, Vol.54 (9), p.7260-7273
• Main Authors: Golemme, Mara, Tatti, Elisa, Di Bernardi Luft, Caroline, Bhattacharya, Joydeep, Herrojo Ruiz, Maria, Cappelletti, Marinella
• Format: Article
• Language: English
• Subjects: alpha resting‐state; electroencephalogram (EEG); Flexibility; Memory; Multivariate analysis; neuronal oscillations; Oscillations; retro‐cues; Short term memory; working memory (WM)
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1111/ejn.15486

The ability to flexibly manipulate memory representations is embedded in visual working memory (VWM) and can be tested using paradigms with retrospective cues. Although valid retrospective cues often facilitate memory recall, invalid ones may or may not result in performance costs. We investigated individual differences in utilising retrospective cues and evaluated how these individual differences are associated with brain oscillatory activity at rest. At the behavioural level, we operationalised flexibility as the ability to make effective use of retrospective cues or disregard them if required. At the neural level, we tested whether individual differences in such flexibility were associated with properties of resting‐state alpha oscillatory activity (8–12 Hz). To capture distinct aspects of these brain oscillations, we evaluated their power spectral density and temporal dynamics using long‐range temporal correlations (LRTCs). In addition, we performed multivariate patterns analysis (MVPA) to classify individuals' level of behavioural flexibility based on these neural measures. We observed that alpha power alone (magnitude) at rest was not associated with flexibility. However, we found that the participants' ability to manipulate VWM representations was correlated with alpha LRTC and could be decoded using MVPA on patterns of alpha power. Our findings suggest that alpha LRTC and multivariate patterns of alpha power at rest may underlie some of the individual differences in using retrospective cues in working memory tasks. We used alpha oscillatory activity at rest to investigate flexibility in visual working memory (VWM), indexed by valid, invalid and neutral retrospective cues. Invalid retro‐cue processing could result in a cost or no‐cost performance. No‐cost performance, reflecting flexible manipulation of VWM representations, was associated with alpha long‐range temporal correlation (LRTC) and distinguished from cost performance using multivariate patterns analysis (MVPA) of alpha power and LRTC.