RT Journal Article SR Electronic T1 Intrinsic reinstatement of induced oscillatory context JF bioRxiv FD Cold Spring Harbor Laboratory SP 2021.01.25.428096 DO 10.1101/2021.01.25.428096 A1 Chantrel, Yoann A1 Trabattoni, Valeria A1 Orton, Lydia A1 Javadi, Amir-Homayoun YR 2021 UL http://biorxiv.org/content/early/2021/01/26/2021.01.25.428096.abstract AB Declarative memory retrieval is thought to rely on the reinstatement, at retrieval, of contextual cues present during encoding, as evidenced in the context and state-dependent literature. Specifically, previous work has shown that reinstating the oscillatory activity present during encoding, at retrieval, is particularly supportive of memory recall. Our study builds on previous findings suggesting that the oscillatory activity present at encoding may be automatically reinstated during retrieval. To explore the roles of consolidation, prefrontal involvement, and frequency specific activity in this process of oscillatory reinstatement, 115 healthy young adults were randomly assigned to one of five conditions. In each condition, transcranial alternating current stimulation (tACS) was administered at either one of two frequencies (60Hz or 6Hz), over the left dorsolateral prefrontal cortex (left-DLPFC, Experimental) or the right primary motor cortex (right-PMC, Control), during learning of written words. This was followed by a retention interval of either 90 minutes or 1 week and a testing phase, during which EEG activity was recorded. Our results showed significant (and frequency specific) oscillatory reinstatement, after stimulation of the left-DLPFC, in the 1-week retention condition. Oscillatory reinstatement effects were non-significant after stimulation of the right-PMC, or in the 90 minutes retention interval condition. Our results highlight that the oscillatory activity induced during encoding is consolidated as context alongside the information and is reinstated intrinsically during retrieval. The implications of our findings for models of human memory, future avenues of research and clinical applications are discussed.Competing Interest StatementThe authors have declared no competing interest.