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bioRxiv · 10.1101/2023.11.08.566069

Unveiling the neural dynamics of conscious perception in rapid object recognition

Abstract

Our brain excels at recognizing objects, even when they flash by in a rapid sequence. However, the neural processes determining whether a target image in a rapid sequence can be recognized or not remained elusive. We used electroencephalography (EEG) to investigate the temporal dynamics of brain processes that shape perceptual outcomes in these challenging viewing conditions. Using naturalistic images and advanced multivariate pattern analysis (MVPA) techniques, we probed the brain dynamics governing conscious object recognition. Our results show that although initially similar, the processes for when an object can or cannot be recognized diverge around 180ms post-appearance, coinciding with feedback neural processes. Decoding analyses indicate that object categorization can occur at [~]120ms through feedforward mechanisms. In contrast, object identification is resolved at [~]190ms after target onset, suggesting involvement of recurrent processing. These findings underscore the importance of recurrent neural connections in object recognition and awareness in rapid visual presentations.

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Motlagh, S. C., Joanisse, M., Wang, B., Mohsenzadeh, Y.. 2023-11-13. Unveiling the neural dynamics of conscious perception in rapid object recognition. https://doi.org/10.1101/2023.11.08.566069

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