Have you ever wondered how your brain figures out the order of events in an instant? It’s a fascinating process, and it’s not as straightforward as it seems. In our latest work with Prof. Alessio Fracasso, we explored how visual masks—images briefly appearing after a stimulus—can distort our sense of time and confuse the sequence of two quickly presented visual events.

Previous research has shown that eye movements or visual masks (which mimic the loss of information during saccades) can affect our perception of timing, making events seem closer in time or even reversing their order. But our study goes further: we found that masks that don’t overlap with the stimuli can also create these distortions. This means our brains can misinterpret temporal order based solely on the timing of the mask, even when the mask doesn’t obscure the target.

Our research focused on temporal order judgments (TOJs)—deciding which of two events happened first. Through two experiments, we tested how different masks, including those in entirely separate visual fields from the stimuli, affected participants’ ability to judge the order of events.

Surprisingly, masks that didn’t spatially overlap with the stimuli caused reversals in perceived order. This suggests that it’s not about losing visual information but about when the mask appears. The mask’s timing acts as an “anchor” for our brain to organize what we see.

These findings reveal how intricately our brains process visual information over time, emphasizing that visual perception isn’t just about what we see, but also when we see it.

You can read further at this link: https://www.biorxiv.org/content/10.1101/2024.12.20.629621v1

Or hear a podcast at this link: https://sciencecast.org/casts/629rgnihwk45