COMBINATORICS OF CANONICAL BASES REVISITED: STRING DATA IN TYPE A

We give a formula for the crystal structure on the integer points of the string polytopes and the *-crystal structure on the integer points of the string cones of type A for arbitrary reduced words. As a byproduct, we obtain defining inequalities for Nakashima–Zelevinsky string polytopes. Furthermore, we give an explicit description of the Kashiwara *-involution on string data for a special choice of reduced word.

Content Word Production during Discourse in Aphasia: Deficits in Word Quantity, Not Lexical–Semantic Complexity

Although limited and reduced connected speech production is one, if not the most, prominent feature of aphasia, few studies have examined the properties of content words produced during discourse in aphasia, in comparison to the many investigations of single-word production. In this study, we used a distributional analysis approach to investigate the properties of content word production during discourse by 46 participants spanning a wide range of chronic poststroke aphasia and 20 neurotypical adults, using different stimuli that elicited three discourse genres (descriptive, narrative, and procedural). Initially, we inspected the discourse data with respect to the quantity of production, lexical–semantic diversity, and psycholinguistic features (frequency and imageability) of content words. Subsequently, we created a “lexical–semantic landscape,” which is sensitive to subtle changes and allowed us to evaluate the pattern of changes in discourse production across groups. Relative to neurotypical adults, all persons with aphasia (both fluent and nonfluent) showed significant reduction in the quantity and diversity of production, but the lexical–semantic complexity of word production directly mirrored neurotypical performance. Specifically, persons with aphasia produced the same rate of nouns/verbs, and their discourse samples covered the full range of word frequency and imageability, albeit with reduced word quantity. These findings provide novel evidence that, unlike in other disorders (e.g., semantic dementia), discourse production in poststroke aphasia has relatively preserved lexical–semantic complexity but demonstrates significantly compromised quantity of content word production. Voxel-wise lesion-symptom mapping using both univariate and multivariate approaches revealed left frontal regions particularly the pars opercularis, IC, and central and frontal opercular cortices supporting word retrieval during connected speech, irrespective of word class or their lexical–semantic complexity.

Visual word form processing deficits driven by severity of reading impairments in children with developmental dyslexia

The visual word form area (VWFA) in the left ventral occipito-temporal (vOT) cortex is key to fluent reading in children and adults. Diminished VWFA activation during print processing tasks is a common finding in subjects with severe reading problems. Here, we report fMRI data from a multicentre study with 140 children in primary school (7.9–12.2 years; 55 children with dyslexia, 73 typical readers, 12 intermediate readers). All performed a semantic task on visually presented words and a matched control task on symbol strings. With this large group of children, including the entire spectrum from severely impaired to highly fluent readers, we aimed to clarify the association of reading fluency and left vOT activation during visual word processing. The results of this study confirm reduced word-sensitive activation within the left vOT in children with dyslexia. Interestingly, the association of reading skills and left vOT activation was especially strong and spatially extended in children with dyslexia. Thus, deficits in basic visual word form processing increase with the severity of reading disability but seem only weakly associated with fluency within the typical reading range suggesting a linear dependence of reading scores with VFWA activation only in the poorest readers.

A bijective proof of Macdonald's reduced word formula

International audience We describe a bijective proof of Macdonald's reduced word identity using pipe dreams and Little's bumping algorithm. The proof extends to a principal specialization of the identity due to Fomin and Stanley. Our bijective tools also allow us to address a problem posed by Fomin and Kirillov from 1997, using work of Wachs, Lenart and Serrano- Stump.

Conjugate words and intersections of geodesics in ℍ2

We investigate intersections of geodesic lines in [Formula: see text] and in an associated tree [Formula: see text], proving the following result. Let [Formula: see text] be a punctured hyperbolic torus and let [Formula: see text] be a closed geodesic in [Formula: see text]. Any edge of any triangle formed by distinct geodesic lines in the preimage of [Formula: see text] in [Formula: see text] is shorter than [Formula: see text]. However, a similar result does not hold in the tree T. Let [Formula: see text] be a reduced and cyclically reduced word in [Formula: see text]. We construct several examples of triangles in [Formula: see text] formed by distinct axes in [Formula: see text] stabilized by conjugates of [Formula: see text] such that an edge in those triangles is longer than [Formula: see text]. We also prove that if [Formula: see text] overlaps two of its conjugates in such a way that the overlaps cover all of [Formula: see text] and the overlaps do not intersect, then there exists a decomposition [Formula: see text], with [Formula: see text] a terminal subword of [Formula: see text] and [Formula: see text] an initial subword of [Formula: see text].

Relative impacts of mild and major neurocognitive disorder on rate of verbal learning acquisition

Objective The California Verbal Learning Test—second edition (CVLT-II) learning slope index may signal the presence of cognitive impairment, though the relative impacts of mild (MiND) and major (MaND) neurocognitive disorders on the rate of verbal learning acquisition remain unknown. Methods Latent intercept-only, linear, quadratic, and exponential models were fit to raw scores for the five CVLT-II learning trials of 197 veterans. Dummy-coded variables reflecting MiND and MaND predicted the growth factors. Results Quadratic growth best fit the data. MiND and MaND predicted reduced recall on each trial. MaND predicted reduced rate of learning acquisition (i.e., word gains per trial) over-and-above MiND, even after controlling for age, sex, education, race/ethnicity, and mono/bilingualism. Conclusions Nonlinear growth—with continuous but diminishing gains over trials—best characterized verbal learning acquisition. Reduced word recall each trial may help differentiate MiND from no neurocognitive disorder, while reduced rate of verbal learning acquisition may help differentiate MaND from MiND.

How much does orthography influence the processing of reduced word forms? Evidence from novel-word learning about French schwa deletion

This study examines the influence of orthography on the processing of reduced word forms. For this purpose, we compared the impact of phonological variation with the impact of spelling-sound consistency on the processing of words that may be produced with or without the vowel schwa. Participants learnt novel French words in which the vowel schwa was present or absent in the first syllable. In Experiment 1, the words were consistently produced without schwa or produced in a variable manner (i.e., sometimes produced with and sometimes produced without schwa). In Experiment 2, words were always produced in a consistent manner, but an orthographic exposure phase was included in which words that were produced without schwa were either spelled with or without the letter <e>. Results from naming and eye-tracking tasks suggest that both phonological variation and spelling-sound consistency influence the processing of spoken novel words. However, the influence of phonological variation outweighs the effect of spelling-sound consistency. Our findings therefore suggest that the influence of orthography on the processing of reduced word forms is relatively small.

Listeners’ processing of a given reduced word pronunciation variant directly reflects their exposure to this variant: Evidence from native listeners and learners of French

In casual conversations, words often lack segments. This study investigates whether listeners rely on their experience with reduced word pronunciation variants during the processing of single segment reduction. We tested three groups of listeners in a lexical decision experiment with French words produced either with or without word-medial schwa (e.g., /ʀvy/ and /ʀvy/ for revue). Participants also rated the relative frequencies of the two pronunciation variants of the words. If the recognition accuracy and reaction times (RTs) for a given listener group correlate best with the frequencies of occurrence holding for that given listener group, recognition is influenced by listeners’ exposure to these variants. Native listeners’ relative frequency ratings correlated well with their accuracy scores and RTs. Dutch advanced learners’ accuracy scores and RTs were best predicted by their own ratings. In contrast, the accuracy and RTs from Dutch beginner learners of French could not be predicted by any relative frequency rating; the rating task was probably too difficult for them. The participant groups showed behaviour reflecting their difference in experience with the pronunciation variants. Our results strongly suggest that listeners store the frequencies of occurrence of pronunciation variants, and consequently the variants themselves.