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bioRxiv · 10.1101/2024.06.11.598529

Improving the Reliability and Accuracy of Population Receptive Field Measures Using a Logarithmically Warped Stimulus.

Chang, K. H.·Fine, I.·Boynton, G. M.
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Abstract

The population receptive field method, which measures the region in visual space that elicits a BOLD signal in a voxel in retinotopic cortex, is a powerful tool for investigating the functional organization of human visual cortex with fMRI (Dumoulin & Wandell, 2008). However, recent work has shown that population receptive field (pRF) estimates for early retinotopic visual areas can be biased and unreliable, especially for voxels representing the fovea. Here, we show that a log-bar stimulus that is logarithmically warped along the eccentricity dimension produces more reliable estimates of pRF size and location than the traditional moving bar stimulus. The log-bar stimulus was better able to identify pRFs near the foveal representation, and pRFs were smaller in size, consistent with simulation estimates of receptive field sizes in the fovea.

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Chang, K. H., Fine, I., Boynton, G. M.. 2024-06-13. Improving the Reliability and Accuracy of Population Receptive Field Measures Using a Logarithmically Warped Stimulus.. https://doi.org/10.1101/2024.06.11.598529

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