Abstract
The presentation of a hand grasp facilitates the recognition of subsequent objects when the grasp is coherent with the object to be identified. This outcome is usually explained as the integration of two different processes: descriptive visual processes in ventral visual areas and processes in charge of the computations of action metrics in dorsal visual regions. With the aim to explore the temporal dynamics of this interaction, we conducted an experiment in which participants categorized objects preceded by congruent and incongruent hand grasp gestures under different interstimulus interval (ISI) conditions. Hand grasp gestures and target objects were separated by five different interstimulus intervals (ISI): 0, 250, 500, 1000, and 2000 ms. Results showed significant shorter response times for congruent trials than for incongruent trials for ISI conditions of 250 and 500 ms. However, no effect was found for the other ISIs (0, 1,000 and 2,000). These results suggest that the contribution of automatically driven visuomotor dorsal areas in object recognition is stronger up to 500 ms after prime offset, and that object identification is facilitated by hand gesture primes just inside this time window (250–500 ms).