Schedule of Events | Symposia

Expectation dynamically modulates the representational time course of objects and locations

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Margaret Moore¹ (margaret.moore@uq.edu.au), Amanda Robinson¹, Jason Mattingley^1,2; ¹University of Queensland, ²Canadian Institute for Advanced Research

Past work has demonstrated that predictive information modulates how the brain responds to visual stimuli, but it is not yet clear how the brain integrates different types of predictive information to facilitate efficient perception. Here, we aim to explore how different types of predictive information modulate the occurrence and directionality of prediction effects in patterns of evoked brain activity. Participants (n = 40) viewed real-world object images in rapid serial visual presentation (RSVP) streams which were predictable both in terms of object identity and stimulus location. Multivariate pattern analyses of electroencephalography (EEG) data were used to quantify and compare the degree of information represented in neural activity when stimuli were random (unpredictable), expected, or unexpected. Decoding accuracy for expected locations was significantly reduced relative to random locations between 160–238 ms post-onset. However, this effect subsequently reversed with decoding accuracy for expected locations becoming higher than accuracy for random locations between 273-430 ms. This temporally dynamic effect was not replicated within analyses decoding object identity. However, consistent evidence for reduced decoding of unexpected relative to random stimuli in later time windows (>250ms) post-onset was identified across both stimulus types (e.g. objects and locations). These findings extend fundamental understanding of how the brain detects and employs predictive relationships to modulate visual perception.

Topic Area: PERCEPTION & ACTION: Vision