Are visual search procedures adapted to the nature of the script?

Letters are processed differently from other shapes in a visual search task where subjects have to decide whether or not a predesignated target symbol is present in a subsequently presented string of five such symbols. If the M-shaped letter search function, which relates correct reaction time to target position, reflects an efficient strategy used in word recognition, it should be produced by skilled readers of English who also read a logographic script. A cross-linguistic study of biscriptal Mandarin/English and monoscriptal English readers (Expt 1) provided evidence of the generality of a basic search strategy for alphabetic targets. Hand-of-response affected the search function in an asymmetric fashion for both groups of readers, and although case differences between target and string increased reaction times overall, the classic M-shaped function remained. In Expt 2, we used a within-subjects design and examined the extent to which biscriptal Mandarin/English readers produced different search functions for letters and logographs. Consistent with expectation, these readers showed an M-shaped function for letters but a more U-shaped function for logographs. Hand-of-response exerted a consistent effect for both types of material. Taken together, these experiments support the view that skilled readers develop script-specific procedures.