Spelling transparency and its impact on short term memory: Evidence from Persian and English

According to the dual-route model of reading (Coltheart, 1978) irregular English words could only be read by directly addressing linguistic information in the mental lexicon (referred to as the lexical route), whilst regular words could be read lexically or via a spelling sound conversion route (referred to as the non-lexical route). The universality of this dual route model developed on the peculiarities of English spelling has been tested amongst other writing systems differing in degree of spelling to sound transparency (e.g. Frost, Katz & Bentin, 1987). The consensus being that as far as skilled reading is concerned, all words, particularly high frequency words, in all languages are read via the lexical route whilst the non-lexical route is involved for reading nonwords or low frequency words (Baluch & Besner, 1991). The question, however, is whether this spelling transparency also has an effect on shortterm memory performance, particularly in view of the role that short-term memory plays in reading comprehension. According to the Levels of Processing hypothesis (Craik & Lockhart, 1972; Tulving, 1973) words that are deeper processed at the time of encoding are more frequently recalled in a subsequent short-term recall than words that are read at a more shallow level. If so, words that are read lexically due to a deeper level of processing should be recalled more than words read via a nonlexical route. In a pioneering research, Baluch and Danaye Tousie(2006a & 2006b) examined the impact of spelling transparency on short-term memory recall of Persian adult and children readers. Persian is a regular language but in practice only three of its six vowels are specified in text thus, like English, approximately half of the words in written Persian are very transparent whilst others are opaque because they are written with consonants only (Baluch, 2005). The results showed that indeed spelling transparency of Persian does have an impact on short-term recall, however task demand as well as level of skill are also important factors to be considered. In an attempt to examine the universality of this finding, in this Chapter the results of memory performance of Persian are compared with a recent pilot study on short-term recall of English regular and irregular words. This Chapter discusses these findings and suggestions are made for follow up research