Previous studies suggest white matter (WM) integrity is vulnerable to chronic hypoperfusion during brain ageing. We assessed ~ 0.7 million capillary profiles in the frontal lobe WM across several dementias comprising Alzheimer’s disease, dementia with Lewy bodies, Parkinson’s disease with dementia, vascular dementia, mixed dementias, post-stroke dementia as well as post-stroke no dementia and similar age ageing and young controls without significant brain pathology. Standard histopathological methods were used to determine microvascular pathology and capillary width and densities in 153 subjects using markers of the basement membrane (collagen IV; COL4) and endothelium (glucose transporter-1; GLUT-1). Variable microvascular pathology including coiled, tortuous, collapsed and degenerated capillaries as well as occasional microaneurysms was present in all dementias. As expected, WM microvascular densities were 20–49% lower than in the overlying cortex. This differential in density between WM and cortex was clearly demonstrated by COL4, which was highly correlated with GLUT-1 densities (Spearman’s rho = 0.79, P = 0.000). WM COL4 immunopositive microvascular densities were decreased by ~ 18% across the neurodegenerative dementias. However, we found WM COL4 densities were increased by ~ 57% in post-stroke dementia versus ageing and young controls and other dementias. Using three different methods to measure capillary diameters, we found WM capillaries to be significantly wider by 19–45% compared to those in overlying neocortex apparent with both COL4 and GLUT-1. Remarkably, WM capillary widths were increased by ~ 20% across all dementias compared to ageing and young controls (P < 0.01). We also noted mean WM pathology scores incorporating myelin loss, arteriolosclerosis and perivascular spacing were correlated with COL4 immunopositive capillary widths (Pearson’s r = 0.71, P = 0.032). Our key finding indicates that WM capillaries are wider compared to those in the overlying neocortex in controls but they dilate further during dementia pathogenesis. We suggest capillaries undergo restructuring in the deep WM in different dementias. This reflects compensatory changes to retain WM perfusion and integrity during hypoperfusive states in ageing-related dementias.

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This study examined the scoring errors across three widely used achievement tests (Kaufman Test of Educational Achievement-Second Edition [KTEA-2], Woodcock-Johnson Tests of Achievement-Third Edition [WJ-III], and the Wechsler Individual Achievement Test-Third Edition [WIAT-III]) by novice examiners. A total of 114 protocols were evaluated for differences between the measures on the frequency and type of scoring errors. Within-measure analyses were also conducted to identify particular composites or subtests that might be more prone to error. Among the three measures, the WIAT-III was found to have the most scoring elements and was, therefore, the measure most susceptible to errors in scoring. Irrespective of the measure, more errors occurred on composites requiring greater examiner inference and interpretation, similar to previous studies on the propensity of scoring errors on cognitive measures. Results are discussed in relation to assessment fidelity and to assessment training practices.

Word-level reading and phonological processing measures were administered in English and Chinese to adult ESL students whose first language (L1) was Mandarin and whose second language (L2) was English. Instructors also identified students who may be at risk for L2 reading difficulties based on specific identification criteria. L2 phonological processing measures were related to L2 word-level reading and there was a cross-linguistic relationship between L1 and L2 phonological processing measures. Students considered at risk for L2 reading difficulties also differed significantly from those students not at risk on one L1 and several L2 phonological processing measures. Results are discussed in relation to contemporary theory on the assessment and identification of reading difficulties in English language learners.Although there has been burgeoning interest and research conducted recently in the early assessment and identification of language minority children who may have literacy problems, the literacy needs of older children and adults with limited English proficiency have been relatively neglected in the research literature (August & Shanahan, 2006). For adult educators of students learning English as a second language (ESL), the assessment and identification of reading difficulties presents a significant challenge. Students come to the centres from heterogeneous linguistic and socioeconomic backgrounds with varying degrees of literacy in their first language (L1). It is also difficult to determine reliably the relative contribution of literacy experience, the impact of acquiring a second language (L2) with a similar as opposed to a dissimilar orthography as the L1 (e.g. alphabetic versus non-alphabetic, shallow versus deep) and the contribution of language proficiency to literacy acquisition in mature ESL students. Additionally, there is research to suggest that generally, educators are not very accurate in identifying those ESL students who may be at risk of reading disabilities (Limbos & Geva, 2001). Further compounding these challenges is the lack of consensus in the field of learning disabilities for operationalising a method for valid and reliable identification (Wagner, Francis & Morrison, 2005).