Semantic priming effects in normal versus poor readers.

The authors studied sensitivity to semantic priming, as distinct from semantic judgment, in poor readers. Association strength (high vs. low semantic association) was manipulated factorially with semantic association type (categoric vs. thematic association). Participants were 11-year-old poor readers (n = 15) who were matched with a group of chronological-age controls (n = 13), and also matched with a group of reading-age controls (n = 15). Three priming conditions were used: related, unrelated, and neutral prime. Neutral primes consisted of a row of hash marks. Related primes elicited shorter decision latencies than did unrelated primes. Neutral primes elicited the slowest responses in all groups. Poor readers showed an additional delay in the neutral prime condition. No effects of association type (categorical vs. thematic) or association strength (high vs. low) were found, nor were any relationship with reading ability found. The delayed performance of the poor readers on neutral primes is explained in terms of orthographic processing and dependency on grapheme phoneme relationships. The findings are discussed with reference to F. R. Vellutino, D. M. Scanlon, and D. Spearing's (1995) work on semantic processing and reading ability.

Contrasting effects of age of acquisition in lexical decision and letter detection.

Two experiments studied attention in beginning and skilled readers of Dutch to letter information in function words and content words. Early and late acquired nouns and function words were presented to third-grade students and skilled adolescent readers. Target words were presented in short story contexts, as in the study of Greenberg, Koriat, and Vellutino (1998). Target nouns were matched on word frequency. Predictions of the structural account hypothesis of letter detection (Koriat, Greenberg, & Goldshmid, 1991) were confirmed. No age-of-acquisition effect was found. In contrast, a separately conducted lexical decision experiment using the same content word stimulus sets showed shorter decision latencies for early acquired words. The combined results suggest that during silent reading, when attention is focused on meaning, phonological processes may play a less prominent role than in lexical decision tasks that demand explicit control of phonological codes. The letter detection results confirmed predictions of the structural account hypothesis for both beginning and skilled readers. Taken together, these studies demonstrate that phonological processes in silent reading may play a less prominent role and that the structural account of letter processing is valid for languages other than Hebrew and English but probably is not the unique mechanism involved in letter detection.

Age-of-acquisition effects in native speakers and second-language learners.

Two lexical decision experiments were conducted to study the locus of age-of-acquisition (AoA) effects in skilled readers with English or Dutch as their first language. AoA effects have generally been explained in terms of phonological processing. In Experiment 1, Dutch elementary school and secondary school students were presented with words factorially manipulated on surface frequency and AoA). Two main effects and an interaction were found, confirming findings reported for English speakers by Gerhand and Barry (1999). In addition, a language development effect was established: AoA effects decreased with reading age. Elementary school students showed the largest AoA effects. Experiment 2 used two groups of subjects. The first group consisted of Dutch students enrolled in a master's degree program in English. The second group consisted of native speakers of English. All subjects were presented with the experimental set of words used by Gerhand and Barry (1999). British subjects showed the same response pattern as reported by Gerhand and Barry (1999). The question of interest was whether Dutch subjects would show an AoA effect on the English set or not. The answer was affirmative. Dutch subjects produced identical response patterns as the British group, showing only an overall 94-msec latency delay. This result challenges predictions of the phonological completeness hypothesis. Alternative accounts in terms of semantic processing are discussed.