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bioRxiv · 10.1101/2024.10.28.620656

Microsaccades strongly modulate but do not cause the N2pc EEG marker of spatial attention

Liu, B.·Kong, S.·van Ede, F.
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Abstract

The N2pc is a popular human-neuroscience marker of covert and internal spatial attention that occurs 200-300 ms after being prompted to shift attention - a time window also characterised by the spatial biasing of microsaccades. Here we show how co-occurring microsaccades profoundly modulate N2pc amplitude during the top-down deployment of spatial attention in both perception and working memory. At the same time, we show that a significant - even if severely weakened - N2pc can still be established in the absence of co-occurring microsaccades. Thus, while microsaccade presence and direction strongly modulate N2pc amplitude, microsaccades are not strictly a prerequisite for the N2pc to be observed.

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Liu, B., Kong, S., van Ede, F.. 2024-10-28. Microsaccades strongly modulate but do not cause the N2pc EEG marker of spatial attention. https://doi.org/10.1101/2024.10.28.620656

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