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bioRxiv · 10.1101/2022.09.29.510214

Harmonic memory signals in the human cerebral cortex induced by sematic relatedness of words

Noguchi, Y.
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Abstract

When we memorize multiple words simultaneously, semantic relatedness among those words assists memory. For example, the information of "apple", "banana" and "orange" will be connected via a common concept of "fruits" and become easy to retain and recall. Neural mechanisms underlying this semantic integration in verbal working memory remain unclear. Here I used electroencephalography (EEG) and investigated neural signals when healthy human participants memorized five nouns semantically related (Sem trial) or not (NonSem trial). The regularity of oscillatory signals (8 - 30 Hz) during the retention period was found to be lower in NonSem than Sem trials, indicating that memorizing words unrelated to each other induced a non-harmonic (irregular) waveform in the temporal cortex. These results suggest that (i) semantic features of a word are retained as a set of neural oscillations at specific frequencies and (ii) memorizing words sharing a common semantic feature produces harmonic brain responses through a resonance or integration (sharing) of the oscillatory signals.

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Noguchi, Y.. 2022-09-30. Harmonic memory signals in the human cerebral cortex induced by sematic relatedness of words. https://doi.org/10.1101/2022.09.29.510214

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