👤 Harmony Grainger

Speech input like [byt] has been shown to facilitate not only the subsequent processing of an identical target word /byt/ but also that of a target word /tyb/ that contains the same phonemes in a different order. In the TISK model of spoken word recognition (Hannagan et al., Frontiers in psychology, 4, 563, 2013), this transposed-phoneme priming effect could result from the activation of shared position-independent phonemes (i.e., a sublexical effect) or pre-activation of the lexical representation corresponding to the transposed-phoneme target word by the prime (i.e., a lexical effect). In this study, we aimed to distinguish sublexical and lexical contributions to transposed-phoneme priming effects by (1) manipulating the lexical status of primes, and (2) examining if transposed-phoneme effects occur when targets are nonwords. An inhibitory transposed-phoneme priming effect was observed when target nonwords (e.g., /tad/) were preceded by transposed-phoneme word primes (e.g., /dat/). In contrast, there was a small non-significant facilitatory priming effect when target nonwords (e.g., /nuk/) were preceded by transposed-phoneme nonword primes (/kun/). These findings point to a greater contribution of lexical representations than sublexical representations in driving transposed-phoneme priming effects. Show less

One essential skill believed to consolidate during the preschool years is children's ability to recognize the different letters of the alphabet. The aim of the present study was to track how visual representations of letters change and are consolidated with exposure to print and the graphomotor experience a child has. A secondary goal of this study was to investigate the emergence of the right visual field advantage for letter identification, reflecting children's sensitivity to the directionality of print. Eighty-one preschool children (aged 4 to 5 years) participated in a longitudinal study where they were shown isolated uppercase letters in both normal upright format and rotated 180°. The letter stimuli were mixed randomly with symbol stimuli in a letter/non-letter lateralized classification task. The results indicated that accuracy in classifying rotated letters as letters-rather than symbols-significantly improved among 4-year-old preschoolers between testing in December (mid-year) and in June (end of the school year). In contrast, little further development was observed in 5-year-old preschoolers, although they still exhibited a slight disadvantage in accuracy when classifying rotated letters. Additionally, behavioral and eye-movement data highlighted a left-to-right deployment of attention by the end of the second year of formal preschool education, evidenced by the emergence of a right visual field advantage. Our results suggest that letter representations undergo significant consolidation during the second year of formal preschool education, which typically corresponds to 4-year-old children in France, with a close relationship between letter identification skills, sensitivity to the directionality of print, and visuo-motor integration skills. Show less

The current study investigated the development of single word processing and multiple word processing skills in French-speaking children from Grade 2 to Grade 6. A total of 150 children participated in two tasks: a Lexical Decision Task (LDT) and a Grammatical Decision Task (GDT). The LDT was used to test single word processing abilities, whereas the GDT was used to test multiple word processing abilities, with stimuli presented at varying display times (LDT: 83-300 ms; GDT: 150-700 ms). Signal detection theory analysis revealed that all children performed well in the LDT, whereas only Grade 4 and Grade 6 children performed above chance in the GDT. A cluster analysis was used to investigate the different types of relation between sensitivity (d') in the LDT and GDT. The analysis revealed two clusters that differed in reading fluency and sensitivity in both tasks. Children from Cluster 2, who exhibited the highest sensitivity in the LDT, were the only ones to perform on average above the chance level in the GDT. Moreover, a strong correlation (r = .64) between LDT and GDT performance was found in this group. Finally, we found that a sensitivity of 1.95 in the LDT almost perfectly predicted cluster membership. Such sensitivity was achieved at Grade 3, suggesting that the ability to process multiple word sequences first requires sufficient efficiency in processing words in isolation. Once this turning point is reached, single word processing skills support the development of multiple word processing, which could take several years to mature fully. Show less

We used a novel nonword detection task to examine the lexical competition principle postulated in most models of spoken word recognition. To do so, in Experiment 1 we presented sequences of spoken words with half of the sequences containing a nonword, and the target nonword (i.e., press a response key whenever you detect a nonword in the sequence) could either be phonologically related (a phonological neighbor) or unrelated to the immediately preceding word. We reasoned that the reactivation of a phonological neighbor during target nonword processing should delay the moment at which a nonword decision can be made. Contrary to our hypothesis, participants were faster at detecting nonwords when they were preceded by a phonological neighbor compared with an unrelated word. In Experiment 2, an inhibitory effect of phonological relatedness on nonword decisions was observed in a classic priming situation using the same set of related and unrelated word-nonword pairs. We discuss the implications of these findings in regard to the main models of spoken word recognition, and conclude that our specific experimental set-up with phonological neighbors embedded in spoken sentences is more sensitive to cooperative interactions between co-activated sublexical representations than lexical competition between co-activated lexical representations, with the latter being modulated by whether or not the words compete for the same slot in time. Show less

We examined the reliance on phonological decoding and morpho-orthographic decomposition strategies in developing and skilled readers of French. A lexical decision experiment was conducted where the critical stimuli were four types of nonwords, all derived from the same base word, such as the French word visage (face) in the following examples: (a) pseudo-homophone (PsH) nonwords (e.g., visaje), (b) orthographic controls for PsH nonwords (e.g., visape), (c) pseudo-morphemic (PsM) nonwords (e.g., visageable), and (d) orthographic controls for PsM nonwords (e.g., visagealle, where alle is not a suffix in French). Responses to PsH and PsM nonwords and their controls were studied in three groups of school children (Grades 1, 2, and 5) and one group of skilled adult readers. PsH interference effects (i.e., more errors to PsH nonwords than to the corresponding controls) decreased during reading acquisition to become nonsignificant in skilled readers. Interestingly, the opposite pattern was seen in PsM interference effects (also measured in terms of accuracy), which were already significant in Grade 1 and increased during reading development to reach their maximum in skilled readers. These results point toward opposing learning trajectories in the use of phonological and morphological information when learning to silently read for meaning. Show less

Atherosclerosis in the carotid arteries is a major cause of ischemic stroke, which accounts for 85% of all stroke cases. Genetic factors contributing to carotid atherosclerosis remain poorly understood. The aim of this study was to identify chromosomal regions harboring genes contributing to carotid atherosclerosis in mice. From an intercross between BALB/cJ (BALB) and SM/J (SM) apolipoprotein E-deficient ( Show less

Individuals with dyslipidemia often develop type 2 diabetes, and diabetic patients often have dyslipidemia. It remains to be determined whether there are genetic connections between the 2 disorders. A female F2 cohort, generated from BALB/cJ (BALB) and SM/J (SM) Apoe-deficient (Apoe(-/-)) strains, was started on a Western diet at 6 weeks of age and maintained on the diet for 12 weeks. Fasting plasma glucose and lipid levels were measured before and after 12 weeks of Western diet. 144 genetic markers across the entire genome were used for quantitative trait locus (QTL) analysis. One significant QTL on chromosome 9, named Bglu17 [26.4 cM, logarithm of odds ratio (LOD): 5.4], and 3 suggestive QTLs were identified for fasting glucose levels. The suggestive QTL near the proximal end of chromosome 9 (2.4 cM, LOD: 3.12) was replicated at both time points and named Bglu16. Bglu17 coincided with a significant QTL for HDL (high-density lipoprotein) and a suggestive QTL for non-HDL cholesterol levels. Plasma glucose levels were inversely correlated with HDL but positively correlated with non-HDL cholesterol levels in F2 mice on either chow or Western diet. A significant correlation between fasting glucose and triglyceride levels was also observed on the Western diet. Haplotype analysis revealed that "lipid genes" Sik3, Apoa1, and Apoc3 were probable candidates for Bglu17. We have identified multiple QTLs for fasting glucose and lipid levels. The colocalization of QTLs for both phenotypes and the sharing of potential candidate genes demonstrate genetic connections between dyslipidemia and type 2 diabetes. Show less