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bioRxiv · 10.1101/2021.03.18.435754

Rhythmic Accessibility to Sequential Working Memory in a Theta Phase-Dependent Manner

Ideriha, T.·Ushiyama, J.
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Abstract

Working memory is active short-term memory storage that is easily accessible for later utilization. There is emerging evidence that memorized items are represented rhythmically on the specific phase of the theta-band (4-7 Hz) neural oscillation. However, it is still unknown how this process impacts the accessibility to the active memory storage. Here we show that simply memorizing sequential information causes theta-band fluctuation in our behaviour (i.e., reaction time, RT). We measured RTs to a visual probe that appeared at sequentially memorized locations after a random interval. Consequently, RTs to the probes fluctuated in the theta range as a function of the random interval, and the behavioural rhythmicity supported the hypothesis of the phase-dependent coding of sequential working memory. The current results demonstrate that our behaviour fluctuates unconsciously in the theta-range when recalling sequential memory, suggesting that accessibility to sequential working memory is rhythmic rather than stable, possibly reflecting theta-phase dependent coding.

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Ideriha, T., Ushiyama, J.. 2021-03-19. Rhythmic Accessibility to Sequential Working Memory in a Theta Phase-Dependent Manner. https://doi.org/10.1101/2021.03.18.435754

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