Beyond stimulus onset: Ongoing fixations within an object do not re-evoke category representations during free-viewing.

Auerbach-Asch, C. R.; Deouell, L. Y.

doi:10.1101/2024.12.02.623991

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bioRxiv · 10.1101/2024.12.02.623991

Beyond stimulus onset: Ongoing fixations within an object do not re-evoke category representations during free-viewing.

Auerbach-Asch, C. R.·Deouell, L. Y.

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Abstract

Human visual perception in natural conditions involves multiple fixations within single objects. While traditional studies focus on transient neural responses to initial stimuli, this study investigates how object-category representations evolve across sequential fixations on an object. Using electroencephalography (EEG) and eye-tracking, we analyzed fixation-related potentials (FRPs) and applied multivariate pattern analysis (MVPA) to decode neural representations of faces and watches during prolonged viewing. Results revealed robust category-selective responses, including the N170 component, at stimulus onset, with sustained representations persisting throughout object presentation. Temporal signal deconvolution showed that subsequent fixations did not re-evoke the N170 but elicited transient occipital responses, likely reflecting low-level differences. These findings underscore the dynamic interplay between transient and sustained neural processes during naturalistic vision and highlight the importance of disentangling overlapping neural signals during free viewing.

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Auerbach-Asch, C. R., Deouell, L. Y.. 2024-12-04. Beyond stimulus onset: Ongoing fixations within an object do not re-evoke category representations during free-viewing.. https://doi.org/10.1101/2024.12.02.623991

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