Word-shape and word-lexical-frequency effects in lexical-decision and naming tasks

Abstract

The present study investigated the use of word-shape information in visual word recognition. Word-shape frequency was computed for lexically frequent and rare words. Experiment 1 contrasted lowercase and uppercase presentations in a lexical-decision task. The observed latencies indicated a shape-frequency effect in lowercase presentation, i.e., responses were given faster for words with a low-frequency shape than for words with a high-frequency shape, and an interaction between shape frequency and lexical frequency, indicating that, for rare words, having a rare shape speeded up lexical decisions. Experiment 2 primed shape information with a 400 ms SOA. The results showed that high-frequency shape words benefited more from the priming procedure than did low-frequency ones. Priming was also used in a naming task (Experiment 3). The results indicated a strong priming effect for all four target types. When all words were given an up-down configuration (Experiment 4), the same pattern of results as in Experiment 1 was found, rejecting a letter-confusability explanation. Taken together, the results suggest that shape information affects word recognition. Having a rare shape seems to shorten lexical decision times on lexically rare words and to lengthen naming times on lexically frequent words.