Transposition Effects in an Aksharic Writing System: The Case of Hindi.

We tested for transposition effects (TEs) in Hindi (a Modern Indo-Aryan language) using unprimed lexical decision. TEs are defined as less accurate and slower responses to transposed-nonwords (e.g., ‹psate›, formed from base-word ‹paste›) than corresponding replaced-nonwords (e.g., ‹pzute›). In Hindi's orthography, letters map transparently to phonemes (except schwa), but the letters are arranged into "akshars," (‹[C]V›) which encode open syllables. This formal characteristic makes Hindi's orthography typologically "aksharic." We used TEs to determine whether the orthography's typological units, letters and akshars, are also functional units for readers. We conducted three visual word recognition experiments with adult readers whose native language was Hindi. In Experiment 1, we found TEs for consonant (‹C›) and matra (‹M›, a vowel diacritic) letters, using different stimulus sets for each type of transposition. In the next two experiments, we used the same base words to form all of the transposed and replaced items. In Experiment 2, we replicated the findings of Experiment 1 in a different stimulus set; additionally, we found TEs for transpositions between a ‹C› letter and a ‹CM› akshar. In Experiment 3, we replicated results of the first two experiments by finding TEs for both consonants and matras in another stimulus set; additionally, we found similar TEs for ‹CM› akshars. These results show that ‹C› and ‹M› letters are functional units for Hindi readers; the transposition results for ‹CM› akshars are tentative. TEs for letters show that the aksharic grouping of letters does not prevent readers from decoding the constituent letters of akshars. Hindi is read alphabetically.