Surface cues reduce the latency to name rotated images of objects

Jolicoeur (1985, Memory & Cognition 13 289-303) found a linear increase in the latency to name line drawings of objects rotated (0 degrees to 120 degr ees) from the upright (0 degrees) in the initial trial block. This effect w as much shallower in later blocks. He proposed that the initial effect may indicate that mental rotation is the default process for recognising rotate d objects, and that the decrease in this effect, seen with practice, may re flect the increased use of learned orientation-invariant features. Initiall y, we were interested in whether object-colour associations that may be lea rned during the initial block, could account for the reduced latency to nam e rotated objects, seen in later blocks. In experiment 1 we used full-cue c olour images of objects that depicted colour and other surface cues. Surpri singly, given that Jolicoeur's findings were replicated several times with line drawings, we found that even the initial linear trend in naming latenc y was shallow. We replicated this result in follow-up experiments. In contr ast, when we used less-realistic depictions of the same objects that had fe wer visual cues (ie line drawings, coloured drawings, greyscale images), th e results were comparable to those of Jolicoeur. Also, the initial linear t rends were steeper for these depictions than for full-cue colour images. Th e results suggest that, when multiple surface cues are available in the ima ge, mental rotation may not be the default recognition process.