Mugs and Plants: Object Semantic Knowledge Alters Perceptual Processing with Behavioral Ramifications

Neural processing of objects with action associations is thought to recruit dorsal visual regions more than objects without such associations. We hypothesized that because the dorsal and ventral visual pathways have differing proportions of magno- and parvo-cellular input, there should be behavioral differences in perceptual tasks between manipulable and non-manipulable objects. This hypothesis was tested using gap detection task, suited to the spatial resolution of the ventral parvocellular processing, and object flicker discrimination task, suited to the temporal resolution of the dorsal magnocellular processing. Directly predicted from the cellular composition of each pathway, a non-manipulable object advantage was observed in tasks relying on spatial resolution, and a manipulable object advantage in temporal discrimination. We also show that these relative advantages are modulated by either reducing object recognition through inversion or by suppressing magnocellular processing using red light. These results establish perceptual differences between objects dependent on prior knowledge and experience.