Thematic knowledge survives visual crowding and influences object identification.

Object perception is challenged in complex and cluttered visual environments. This phenomenon, known as visual crowding, occurs when object identification is impaired because a target is surrounded by other objects. However, visual environments are meaningful, and objects are often arranged in coherent and predictable ways. In particular, thematic relations linking objects that play complementary roles in events (e.g., hammer–nail) facilitate conceptual processing, especially for manipulable objects. However, it remains unclear whether such semantic relations can also influence perceptual processes. This study investigated whether thematic information can be processed under visual crowding and facilitate object identification in clutter. Participants were briefly presented with pairs of object images in peripheral vision and performed an object identification task. The object pairs were either thematically related or unrelated, and correctly positioned for being used together or not. Objects were presented either in isolation or crowded by meaningless flankers. Experiment 1 demonstrated that objects in thematically related pairs were identified more accurately than those in unrelated pairs, even under crowding. Experiment 2 showed that the thematic benefit may occur at the decisional stage for isolated objects, thematic grouping may arise in crowding conditions. Experiment 3 provided a single-object baseline and indicated that thematic relatedness reduced the interference caused by object presentation in pairs. Overall, findings suggest that semantic knowledge involving the use of manipulable objects can survive visual crowding and influence object recognition. They support an embodied view of perception, according to which action-related semantic knowledge can modulate relatively early stages of visual processing.