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Abstract

We present the first studies to examine view effects on the haptic identification of familiar objects. Plastic models were created for twenty pairs of similarly-shaped familiar objects (e.g., chair/bed; dog/pig; car/van; bath/sink) and a morph between each pair. Objects at fixed orientations were presented sequentially behind an occluder in three matching studies. We tested how 90º depth rotations from the first to the second object influenced people's ability to detect shape changes. Task difficulty varied from easy (mismatch trials presented objects from different object pairs) to moderate (mismatches presented both objects from a pair) to hard (mismatches presented an object and
its morph). View changes from the first to the second object always impaired performance. However, surprisingly, unlike our results for the same objects presented visually in the same task, the disruptive effects of task-irrelevant rotations were no greater for harder tasks. Thus although viewpoint influences both visual and haptic object
identification, its effects are probably due to different processes, since the difficulty of shape discrimination only influences visual matching.