Abstract
Seeing an object activates the visual representation of that object (e.g., a “sailboat”) as well as the representations of related objects. This indirect activation depends on the strength of the association. Strongly related objects include different exemplars from the same basic-level category (e.g., a “speedboat”) and objects that share the same context with the viewed object (e.g., an “anchor”). Studying these associations and the order of their activation can reveal how the representations of visual objects are clustered. We used a paradigm that interrupted the post-exposure processing at different latencies from stimulus presentation, such that it was possible to follow the time-course of associative activation. Participants viewed target pictures that were presented rapidly, each embedded within a series of preceding and following masking stimuli. We manipulated the inter-stimulus interval (ISI) between the target image and the buffering masks (0, 250, 500 ms). Each sequence was followed by an object-naming block that included a non-related control object and either the target object, a different exemplar, or a contextually-related object. Naming reaction time provided an estimate of recognition priming and, presumably, an assessment of the relative strength of the associations. Priming of the target pictures was evident for all ISIs. Surprisingly, significant priming was also evident for the contextually related objects (e.g., hammer-nail) even at ISI=0 ms. Priming of different-exemplars, however, was obtained only for ISI=500 ms. This result implies that seeing an object simultaneously activates the representation of this object as well as the representations of objects that are strongly associated with it. Implication to the cortical organization of objects' representations will be proposed.