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bioRxiv · 10.1101/2024.08.20.608807

Neural dynamics of visual streams interactions during memory-guided actions investigated by intracranial EEG

Moraresku, S.·Hammer, J.·Dimakopoulos, V.·Kajsova, M.·Janca, R.·Jezdik, P.·Kalina, A.·Marusic, P.·Vlcek, K.
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Abstract

The dorsal and ventral visual streams play distinct roles in visual processing for action: the dorsal stream is assumed to support real-time actions, while the ventral stream facilitates memory-guided actions. As the recent evidence suggests a more integrated function of these streams, we investigated the neural dynamics and functional connectivity between them during memory-guided actions using intracranial EEG. We tracked neural activity in the inferior parietal lobule in the dorsal stream, and ventral temporal cortex in the ventral stream as well as hippocampus during a delayed action task. We found increased alpha power in both streams during the delay, indicating their role in maintaining visual information. We also observed an increase in theta band synchronization between the inferior parietal lobule and ventral temporal cortex, and between the inferior parietal lobule and hippocampus during the delay. Our study provides unique electrophysiological evidence for close interactions between dorsal and ventral streams, supporting an integrated processing model.

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Moraresku, S., Hammer, J., Dimakopoulos, V., Kajsova, M., Janca, R., Jezdik, P., Kalina, A., Marusic, P., Vlcek, K.. 2024-08-21. Neural dynamics of visual streams interactions during memory-guided actions investigated by intracranial EEG. https://doi.org/10.1101/2024.08.20.608807

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