Martina Morea
PhD student in Neuroscience at the Laboratory of Psychophysics, EPFL Switzerland #VisionScience
- Check out our new publication "Dynamics of Vision: Grouping takes longer than Crowding" where we show that visual perception relies on time-consuming grouping mechanisms. jov.arvojournals.org/article.aspx... #Neuroscience #VisionScience #PsychSciSky #Neuroskyence #Compneurosky
- A special thank you to the LPSY lab in Lausanne (led by Prof Michael Herzog), Prof Greg Francis and @mauromanassi.bsky.social from @abdnpsych.bsky.social for this exciting collaboration on this project which took many years and thought to interpret the results! 🧵9/9 #VisionScience #PsychSciSky
- Our novel #preview effect highlights the importance of #spatio-temporalGrouping in #crowding. In contrast to classic feedforward models, we propose that crowding is a dynamic process where multiple interpretations are modulated and gated by grouping mechanisms evolving over time 🧵8/9
- Our findings are well predicted by the #LAMINART model (Francis et al. 2017), which employs #recurrent segmentation processes unfolding over time to separate objects into distinct representation layers 🧵7/9
- Our results cannot be explained by unspecific priming, as our #preview effect is gated by #grouping processes over time and it occurs only when flankers have the potential to be grouped away from the target for longer stimulus durations (i.e. it does not work for lines) 🧵6/9
- This #preview effect occurs over a long temporal range (i.e., even when the flankers’ preview is one second before the target!) 🧵5/9
- Next, we investigated whether a brief #preview of the flankers could initiate their grouping away from the target, thereby reducing crowding for a target presented later. The answer is Yes! This preview effect showed that uncrowding can be initiated over time depending on grouping 🧵4/9
- Here, we show that #Crowding is modulated by #Grouping, a time-consuming phenomenon. For short durations, flanker grouping does not occur and crowding remains strong. For longer durations, there is enough time to group flankers away from the target, leading to #Uncrowding 🧵3/9
- #VisualCrowding, where nearby items disrupt perception, has been explained within this framework, suggesting that early feedforward processing is crucial under crowding conditions. In accordance with this view, stimulus duration was considered not to play a role in crowding 🧵2/9
- #Vision is often described as hierarchical and feedforward, progressing from low-level features to high-level representations. But are the early #feedforward stages truly the most essential for #perception? Let us show you why not jov.arvojournals.org/article.aspx... 🧵1/9
