The processing of root morphemes in Hebrew: Contrasting localist and distributed accounts

Abstract

The present paper investigates whether Semitic languages impose a rigid triconsonantal structural principle on root-morpheme representation, by examining morphological priming effects obtained with primes consisting of weak roots. For weak roots, the complete three-consonantal structure is not kept in most of their derivations, and only two letters are consistently repeated in all derivations. In a series of masked priming experiments subjects were presented with primes consisting of the weak roots letters which are repeated in all derivations. The results showed that the two consistent letters of weak roots facilitated the recognition of targets derived from these roots. In contrast, any two letters of complete roots did not facilitate the recognition of complete root derivations. The implications of these results to Parallel-Distributed models and to localist-representational approaches, are discussed.Although lexical structure is traditionally regarded as an interplay of orthographic, phonological, and semantic units, the view that morphological considerations need to be introduced into any model of the mental lexicon has been gaining increasing support. How morphological factors determine lexical organisation is, however, the focus of recent debates. Two contrasting approaches can be outlined to describe the present controversy. The Parallel-Distributed Processing (PDP) view of lexical Correspondence should be addressed to Ram Frost,

The developing mental lexicon: evidence from morphological priming of irregular Hebrew forms

“…Furthermore, the magnitude of priming was comparable in the two grades. The morphological priming effect replicates the priming found for defective roots in adults (Velan et al, 2005) and is comparable to the priming obtained in children for morphologically regular words in Hebrew (Raveh & Yamin, 2005). The priming effect suggests that a tri-consonantal root representation has been established in the mental lexicon of young readers despite the inconsistent orthographic appearance of the root, i.e.…”

“…Now we tested whether a target in defective form can benefit from the prior presentation of a prime consisting of the two root letters which are repeated in all the root derivations. Such a priming effect was found by Velan et al (2005) with adult skilled readers, suggesting that the two root letters acquire a special morphological status perhaps due to their consistent appearance in the surface orthography. The question addressed in Experiment 3 was whether the two root letters of defective roots similarly have a morphological status in the mental lexicon of young readers.…”

“…An identity priming condition was also included, where the primes are identical to the targets, as a baseline measure of the maximal possible priming possible. Finally, in contrast to Velan et al (2005), our measure of priming was based on naming latencies, since this is a more natural task for young readers.…”

“…The stimuli of this and the following experiments were based on Velan et al (2005). They consisted of 36 target words, four to six letters long, two or three syllables and five to eight phonemes.…”

“…Using the masked priming paradigm to investigate the morphemic representations of defective roots, Velan, Frost, Deutsch and Plaut (2005) addressed these questions in adults. The two root letters of the defective roots primed target words derived from these roots (e.g., GV primed maGeVet "towel"), suggesting that these two letters do gain a morphemic status, perhaps because they consistently appear in the surface form of many words.…”