Number Processing and Arithmetic in Children and Adults with Reading Difficulties

Author(s):  
Silke M. Göbel

Basic number processing skills in individuals with reading difficulties (RD) are intact. However, children and adults with RD show clear difficulties in arithmetic, in particular in retrieving known answers from long-term memory (fact retrieval). Fact retrieval deficits are associated with weaknesses in phonological awareness, the ability to segment and manipulate speech sounds. The left angular gyrus has been suggested as a site of neurological overlap between RD and fact retrieval deficits. While there is evidence for an involvement of the angular gyrus in fact retrieval in adults, the evidence for children is less clear. The same genetic risk factors may underlie difficulties in reading and mathematics and cause the high co-morbidity between RD and mathematical difficulties. Implications for interventions are discussed.

2021 ◽  
Author(s):  
Stefan Smaczny ◽  
Christoph Sperber ◽  
Stefanie Jung ◽  
Korbinian Moeller ◽  
Hans-Otto Karnath ◽  
...  

Arithmetic fact retrieval has been suggested to recruit a left-lateralized network comprising perisylvian language areas, parietal areas such as the angular gyrus (AG), and subcortical structures such as the hippocampus. However, the underlying white matter connectivity of these areas has not been evaluated systematically so far. Using simple multiplication problems, we evaluated how disconnections in parietal brain areas affected arithmetic fact retrieval following stroke. We derived disconnectivity measures by jointly considering data from n=73 patients with acute unilateral lesions in either hemisphere and a white-matter tractography atlas (HCP-842) using the Lesion Quantification Toolbox (LQT). Whole-brain voxel-based analysis indicated a left-hemispheric cluster of white matter fibers connecting the AG and superior temporal areas to be associated with a fact retrieval deficit. Subsequent analyses of direct grey-to-grey matter disconnections revealed that disconnections of additional left-hemispheric areas (e.g., between the superior temporal gyrus and parietal areas) were significantly associated with the observed fact retrieval deficit. Results imply that disconnections of parietal areas (i.e., the AG) with language-related areas (i.e., superior and middle temporal gyri) seem specifically detrimental to arithmetic fact retrieval. This suggests that arithmetic fact retrieval recruits a widespread left-hemispheric network and emphasizes the relevance of white matter connectivity for number processing.


2005 ◽  
Vol 43 (11) ◽  
pp. 1609-1624 ◽  
Author(s):  
Elena Rusconi ◽  
Vincent Walsh ◽  
Brian Butterworth

2021 ◽  
Vol 18 ◽  
Author(s):  
Luoyu Wang ◽  
Qi Feng ◽  
Mei Wang ◽  
Tingting Zhu ◽  
Enyan Yu ◽  
...  

Background: As a potential brain imaging biomarker, amplitude of low frequency fluc-tuation (ALFF) has been used as a feature to distinguish patients with Alzheimer’s disease (AD) and amnestic mild cognitive impairment (aMCI) from normal controls (NC). However, it remains unclear whether the frequency-dependent pattern of ALFF alterations can effectively distinguish the different phases of the disease. Methods: In the present study, 52 AD and 50 aMCI patients were enrolled together with 43 NC in total. The ALFF values were calculated in the following three frequency bands: classical (0.01-0.08 Hz), slow-4 (0.027-0.073 Hz) and slow-5 (0.01-0.027 Hz) for the three different groups. Subsequently, the local functional abnormalities were employed as features to examine the effect of classification among AD, aMCI and NC using a support vector machine (SVM). Results: We found that the among-group differences of ALFF in the different frequency bands were mainly located in the left hippocampus (HP), right HP, bilateral posterior cingulate cortex (PCC) and bilateral precuneus (PCu), left angular gyrus (AG) and left medial prefrontal cortex (mPFC). When the local functional abnormalities were employed as features, we identified that the ALFF in the slow-5 frequency band showed the highest accuracy to distinguish among the three groups. Conclusion: These findings may deepen our understanding of the pathogenesis of AD and suggest that slow-5 frequency band may be helpful to explore the pathogenesis and distinguish the phases of this disease.


2021 ◽  
Vol 13 ◽  
Author(s):  
NanNan Gu ◽  
Hechun Li ◽  
Xinyi Cao ◽  
Ting Li ◽  
Lijuan Jiang ◽  
...  

The entorhinal cortex (EC) plays an essential role in age-related cognitive decline. However, the effect of functional connectivity (FC) changes between EC and other cerebral cortices on cognitive function remains unclear. The aim of this study was to explore the modulation of two interventions (cognitive training and aerobic exercise) on EC-FC in community-dwelling older adults. In total, 94 healthy older adults aged between 65 and 75 years were assigned to either the cognitive training or aerobic exercise group to receive 24 sessions over 12 weeks, or to a control group. Resting-state functional magnetic resonance imaging was performed at both baseline and 12-month follow-up. Compared to the cognitive training group, the aerobic exercise group showed greater EC-FC in the bilateral middle temporal gyrus, right supramarginal gyrus, left angular gyrus, and right postcentral gyrus. Compared to the control group, the cognitive training group had a decreased EC-FC in the right hippocampus, right middle temporal gyrus, left angular gyrus, and right postcentral gyrus and an increased EC-FC in the bilateral pallidum, while the aerobic exercise group showed increased EC-FC between the right medial prefrontal cortex(mPFC), bilateral pallidum, and right precuneus. Baseline EC-FC in the mPFC was positively correlated with the visuospatial/constructional index score of the Repeatable Battery for the Assessment of Neuropsychological Status. In the cognitive training group, EC-FC value changes in the right hippocampus were negatively correlated with changes in the RBANS delayed memory index score, while in the aerobic exercise group, EC-FC value changes in the left angular gyrus were positively correlated with changes in the RBANS attention index score. These findings support the hypothesis that both cognitive training and aerobic exercise can modulate EC-FC in aging populations but through different neural pathways.


2021 ◽  
Author(s):  
Edoardo Nicolò Aiello ◽  
Sarah Feroldi ◽  
Alice Naomi Preti ◽  
Stefano Zago ◽  
Ildebrando Marco Appollonio

AbstractBackgroundMotor neuron disease (MND) patients can show oral language deficits mimicking those of frontotemporal degenerations (FTD). Although dysgraphic features have been also reported within the MND-FTD continuum, their characteristics and clinical relevance are still largely unexplored.AimsTo profile writing disorders in MND patients can help further define their cognitive semiology and thus conveys relevant clinical entailments. Therefore, this study aimed at reviewing evidence of writing impairment in MND patients. This review was implemented and reported by consulting Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Qualitative/quantitative measures of writing abilities in MND patients was the primary outcome. Both group studies and case reports/series were taken into consideration. Twenty-four contributions were included out of an initial N=83. Potential biases in generalizing results were qualitatively controlled for by extracting background, disease-related, neuropsychological and neuroanatomofunctional secondary outcomes.Main ContributionFifteen studies assessed writing abilities in Japaneses patients, whereas the remaining eight in western patients. Central dysgraphic features were reported in both neuropsychologically-impaired and –unimpaired MND patients. Phonetic/phonological paragraphias and morpho-syntactic errors were frequently reported. Although FTD was frequently co-occurent, neither cognitive nor language impairment fully accounted for writing impairment in some patients. By contrast, evidence of peripheral dysgraphia was scarce. Patients displaying writing deficits often presented with bulbar signs and perisylvian cortices involvement (including Exner’s area and the left angular gyrus). Writing deficits proved to be associated with abnormalities in executive functioning and its neural substrates. Writing-to-dictation tasks as well as writing samples assessment proved to be useful to detect writing errors.ConclusionsDysgraphic features in MND patients might be due to dysfunctions of the graphemic buffer – and possibly the phonological route. The lexico-semantic route appeared to be less involved. However, a mixed peripheral/central involvement cannot be ruled out. In this population, executive/attentive deficits are likely to contribute to writing errors as well. Writing deficits might thus be specific of MND patients’ cognitive/language impairment profile. The evaluation of writing abilities via writing-to-dictation/narrative writing tasks may be useful when assessing cognition/language in both neuropsychological-impaired and -unimpaired MND patients - especially when severe dysarthria/anarthria is present and prevents clinicians from assessing oral language.


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