Visual Responses to Symmetries in Textures and Objects

Symmetry is a striking and pervasive feature of the visual world, found in both natural and human-made environments. It has long been thought to play a key role in mid-level visual processing, helping the brain recover the underlying structure of visual scenes. In this talk, I will share research exploring how humans perceive and represent visual symmetries, using brain imaging and behavioral methods with novel stimuli and paradigms. The first part of the talk focuses on wallpaper groups—the complete set of symmetries possible in two-dimensional patterns. Using functional MRI and steady-state EEG, these studies reveal a feedforward network of visual areas that encode remarkably precise representations of symmetry. Strikingly, brain responses to symmetry are highly similar between humans and non-human primates and closely aligned with behavioral sensitivity. Building on this foundation, I will discuss evidence that symmetry processing benefits from texture regularity and describe ongoing work exploring the spatial tuning of symmetry responses. The final part of the talk presents recent studies that aim to bring symmetry research closer to natural vision. This includes investigations of how the brain processes symmetries in 3D objects that are subject to perspective distortion, and novel evidence suggesting a relationship between object familiarity and symmetry processing. Time permitting, I will conclude by showing how the EEG methods used here can be applied to broader questions in visual neuroscience.

Alternate locations:

 Online: https://utoronto.zoom.us/j/88523051719