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bioRxiv · 10.1101/148635

Fluctuations of fMRI activation patterns reveal theta-band dynamics of visual object priming

Guo, B.·Lu, Z.·Goold, J. E.·Luo, H.·Meng, M.
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Abstract

The brain dynamically creates predictions about upcoming stimuli to guide perception efficiently. Recent behavioral results suggest theta-band oscillations contribute to this prediction process, however litter is known about the underlying neural mechanism. Here, we combine fMRI and a time-resolved psychophysical paradigm to access fine temporal-scale profiles of the fluctuations of brain activation patterns corresponding to visual object priming. Specifically, multi-voxel activity patterns in the fusiform face area (FFA) and the parahippocampal place area (PPA) show temporal fluctuations at a theta-band (~5 Hz) rhythm. Importantly, the theta-band power in the FFA negatively correlates with reaction time, further indicating the critical role of the observed cortical theta oscillations. Moreover, alpha-band (~10 Hz) shows a dissociated spatial distribution, mainly linked to the occipital cortex. These findings, to our knowledge, are the first fMRI study that indicates temporal fluctuations of multi-voxel activity patterns and that demonstrates theta and alpha rhythms in relevant brain areas.

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Guo, B., Lu, Z., Goold, J. E., Luo, H., Meng, M.. 2017-06-12. Fluctuations of fMRI activation patterns reveal theta-band dynamics of visual object priming. https://doi.org/10.1101/148635

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