Rahman, R. A. | Search bioRxiv

bioRxiv2026

Expectation Shapes Neural Preparation for AI-generated and Real Image Processing: Evidence from EEG

AbstractAI-generated images, videos, and news have become an inseparable part of daily life, leading to increasing skepticism toward online information. Understanding how expectations about the presence of AI-generated content influence perception is crucial for elucidating the underlying neural mechanisms and facilitating the generation of naturalistic avatars. In this study, we analyzed an existing EEG dataset (N = 29) in which participants viewed emotional facial photographs of only real individuals while being informed that upcoming faces were either real ("REAL") or AI-generated ("FAKE"). We examined pre-stimulus oscillatory activities in the one-second EEG interval before stimulus onset and found significantly lower alpha power when participants expected "FAKE" compared to "REAL" faces. This effect was region-specific, particularly in right occipito-parietal and temporo-parietal regions, as identified by both sensor- and source- level analyses. In addition, the modulation effect between pre-stimulus alpha activity and post-stimulus event-related potentials (ERPs) was measured. A significant correlation between changes in late positive potential (LPP) amplitudes and pre-stimulus alpha power was observed exclusively for "FAKE" smiling faces, consistent with our previous findings. These results suggest that AI-related expectations modulate neural preparatory states, with lower alpha activity presumably reflecting increased attentional demands for stimuli believed to be artificially generated. This study demonstrates that top-down beliefs systematically shape both pre- and post-stimulus neural dynamics, providing new insights into how cognitive expectations bias perceptual processing, with implications for understanding human-AI interaction and improving the design and evaluation of AI- generated content in real-world contexts.

neuroscience↗

bioRxiv2026

From Sensory Details to Verbal Codes: Visual Memory Reinstatement of Location and Color Features

Successful episodic memory depends on the reinstatement of encoding content and processes during retrieval. However, it remains unclear how such reinstatement (1) differs for various perceptual features, (2) supports subjective versus objective memory retrieval, and (3) relies on linguistic information. To investigate these three issues, we designed an fMRI study in which participants encoded and recalled the colors and spatial locations of object pictures, and provided subjective vividness and objective precision measures. We used encoding-retrieval similarity (ERS) to identify feature-level reinstatement for location or color features, and trial-specific reinstatement for individual location trials or individual color trials. The study yielded three main findings. First, feature-level reinstatement in frontoparietal and visual regions supported both location and color memory, whereas trial-specific reinstatement in early visual cortex contributed to location memory and feature-level reinstatement in lateral/anterior temporal cortices, to color memory. Second, trial-specific reinstatement in early visual cortex supported both location vividness and precision, while feature-level reinstatement in inferior frontal gyrus contributed to color vividness, and trial-specific reinstatement in posterior inferior temporal gyrus (including the color area), to color precision. Finally, color name richness (the number of names associated with a particular color) enhanced color memory precision and modulated trial-specific color reinstatement in right anterior inferior temporal gyrus. Together, these findings suggest that perceptual and linguistic reinstatement play complementary roles in visual episodic memory: perceptual replay provides fine-grained sensory details, whereas linguistic replay can scaffold and refine these representations, especially for features that are easier to verbalize such as colors. Significance StatementNeural reinstatement has been associated with the quality of episodic memory for complex visual images. However, it remains unclear how neural reinstatement varies across perceptual features, memory subjectivity, and linguistic accessibility. Here, we examine how neural reinstatement supports memory for color and location, whether it plays different roles in memory vividness versus precision, and the role of language in color memory. We showed that location memory relies primarily on trial-specific reinstatement in early visual cortex, supporting precise and vivid recall, whereas color memory is supported by a more complex and complementary interplay between perceptual and linguistic reinstatement. Together, these results advance our understanding of how distinct reinstatement mechanisms support the precision and vividness of episodic memory for basic visual features.

neuroscience↗