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Frontiers in Human Neuroscience 2021Dyscalculia is a learning disability affecting the acquisition of arithmetical skills in children with normal intelligence and age-appropriate education. Two hypotheses...
Dyscalculia is a learning disability affecting the acquisition of arithmetical skills in children with normal intelligence and age-appropriate education. Two hypotheses attempt to explain the main cause of dyscalculia. The first hypothesis suggests that a problem with the core mechanisms of perceiving (non-symbolic) quantities is the cause of dyscalculia (core deficit hypothesis), while the alternative hypothesis suggests that dyscalculics have problems only with the processing of numerical symbols (access deficit hypothesis). In the present study, the symbolic and non-symbolic numerosity processing of typically developing children and children with dyscalculia were examined with functional magnetic resonance imaging (fMRI). Control ( = 15, mean age: 11.26) and dyscalculia ( = 12, mean age: 11.25) groups were determined using a wide-scale screening process. Participants performed a quantity comparison paradigm in the fMRI with two number conditions (dot and symbol comparison) and two difficulty levels (0.5 and 0.7 ratio). The results showed that the bilateral intraparietal sulcus (IPS), left dorsolateral prefrontal cortex (DLPFC) and left fusiform gyrus (so-called "number form area") were activated for number perception as well as bilateral occipital and supplementary motor areas. The task difficulty engaged bilateral insular cortex, anterior cingulate cortex, IPS, and DLPFC activation. The dyscalculia group showed more activation in the left orbitofrontal cortex, left medial prefrontal cortex, and right anterior cingulate cortex than the control group. The dyscalculia group showed left hippocampus activation specifically for the symbolic condition. Increased left hippocampal and left-lateralized frontal network activation suggest increased executive and memory-based compensation mechanisms during symbolic processing for dyscalculics. Overall, our findings support the access deficit hypothesis as a neural basis for dyscalculia.
PubMed: 34354576
DOI: 10.3389/fnhum.2021.687476 -
Dementia & Neuropsychologia 2021Brazilian students' mathematical achievement was repeatedly observed to fall below average levels of mathematical attainment in international studies such as PISA.
UNLABELLED
Brazilian students' mathematical achievement was repeatedly observed to fall below average levels of mathematical attainment in international studies such as PISA.
OBJECTIVE
In this article, we argue that this general low level of mathematical attainment may interfere with the diagnosis of developmental dyscalculia when a psychometric criterion is used establishing an arbitrary cut-off (e.g., performance
METHODS
Therefore, the present study evaluated the performance of 706 Brazilian school children from 3 to 5 grades on basic arithmetic operations addition, subtraction, and multiplication.
RESULTS
In line with PISA results, children presented difficulties in all arithmetic operations investigated. Even after five years of formal schooling, less than half of 5 graders performed perfectly on simple addition, subtraction, or multiplication problems.
CONCLUSIONS
As such, these data substantiate the argument that the sole use of a psychometric criterion might not be sensible to diagnose dyscalculia in the context of a generally low performing population, such as Brazilian children of our sample. When the majority of children perform poorly on the task at hand, it is hard to distinguish atypical from typical numerical development. As such, other diagnostic approaches, such as Response to Intervention, might be more suitable in such a context.
PubMed: 34345369
DOI: 10.1590/1980-57642021dn15-020015 -
Frontiers in Pediatrics 2021Pediatric acute-onset neuropsychiatric syndrome (PANS) is a condition defined by sudden onset of obsessive-compulsive symptoms and/or severe eating restrictions, along...
Pediatric acute-onset neuropsychiatric syndrome (PANS) is a condition defined by sudden onset of obsessive-compulsive symptoms and/or severe eating restrictions, along with at least two other cognitive, behavioral, or neurological symptoms. Its pathogenesis is unknown but it seems triggered by infections, metabolic disturbances, and other inflammatory reactions. PANS represents a neurodevelopmental problem and infant feeding can play a role. Breast milk is the ideal food for infants and influences children's brain, cognitive, and socio-emotional development. We enrolled 52 children diagnosed with PANS. We interviewed their parents in order to investigate perinatal history, infant feeding, neurologic development, and confounding factors like socio-economic status and region of origin. We subgrouped PANS patients into three subsets: those who only received human milk (HMO), those who only received infant formula, and those who received mixed feeding. The cohort is composed of 78.9% males, with a median age of 11 years (range 7-17). We found some neurodevelopmental problems (13.5%): walking disorders, ASD, ADHD, oppositional attitude, and delayed psychomotor development. We found scholar performance deficits (25%), including language problems like dysgraphia, dyslexia, and dyscalculia. The achievement of some milestones in the development of the infant is affected in 73.1% of cases. Breastfeeding is not homogeneously practiced in Italy because of social, economic, and cultural phenomena. The richest and the poorest families (100%) in the sample choose breastfeeding, probably with a different approach and for different reasons (awareness or need). In the group of PANS patients fed with HMO, compared to the rest of the patients, we registered fewer cases of growth problems (0 vs. 12.9%; = 0.14), school performance problems or the need for school support (19.1% vs. 29%; = 0.42), and a delay in the age of babbling/speaking (range 4-20 vs. 7-36 months; = 0.066). This is the first study that investigates the role of breastfeeding in the development of PANS. Promoting breastfeeding is important in the general population and also in PANS patients because it has an important social and global health impact, also during adult life. Further studies with a bigger population are needed to investigate the mechanisms underlying PANS and the role that breastfeeding may play in their short- and long-term neurodevelopment.
PubMed: 34307255
DOI: 10.3389/fped.2021.682108 -
NPJ Science of Learning Jul 2021The development of numerical and arithmetic abilities constitutes a crucial cornerstone in our modern and educated societies. Difficulties to acquire these central... (Review)
Review
The development of numerical and arithmetic abilities constitutes a crucial cornerstone in our modern and educated societies. Difficulties to acquire these central skills can lead to severe consequences for an individual's well-being and nation's economy. In the present review, we describe our current broad understanding of the functional and structural brain organization that supports the development of numbers and arithmetic. The existing evidence points towards a complex interaction among multiple domain-specific (e.g., representation of quantities and number symbols) and domain-general (e.g., working memory, visual-spatial abilities) cognitive processes, as well as a dynamic integration of several brain regions into functional networks that support these processes. These networks are mainly, but not exclusively, located in regions of the frontal and parietal cortex, and the functional and structural dynamics of these networks differ as a function of age and performance level. Distinctive brain activation patterns have also been shown for children with dyscalculia, a specific learning disability in the domain of mathematics. Although our knowledge about the developmental brain dynamics of number and arithmetic has greatly improved over the past years, many questions about the interaction and the causal involvement of the abovementioned functional brain networks remain. This review provides a broad and critical overview of the known developmental processes and what is yet to be discovered.
PubMed: 34301948
DOI: 10.1038/s41539-021-00099-3 -
Frontiers in Psychology 2021We report on the first in-depth analysis of a specific type of dysnumeria, number-reading deficit, in sign language. The participant, Nomi, is a 45-year-old signer of...
We report on the first in-depth analysis of a specific type of dysnumeria, number-reading deficit, in sign language. The participant, Nomi, is a 45-year-old signer of Israeli Sign Language (ISL). In reading multidigit numbers (reading-then-signing written numbers, the counterpart of reading aloud in spoken language), Nomi made mainly decimal, number-structure errors- reading the correct digits in an incorrect (smaller) decimal class, mainly in longer numbers of 5-6-digits. A unique property of ISL allowed us to rule out the numeric-visual analysis as the source of Nomi's dysnumeria: In ISL, when the multidigit number signifies the number of objects, it is signed with a decimal structure, which is marked morphologically (e.g., 84 → Eight-Tens Four); but a parallel system exists (e.g., for height, age, bus numbers), in which multidigit numbers are signed non-decimally, as a sequence of number-signs (e.g., 84 → Eight, Four). When Nomi read and signed the exact same numbers, but this time non-decimally, she performed significantly better. Additional tests supported the conclusion that her early numeric-visual abilities are intact: she showed flawless detection of differences in length, digit-order, or identity in same-different tasks. Her decimal errors did not result from a number-structure deficit in the phonological-sign output either (no decimal errors in repeating the same numbers, nor in signing multidigit numbers written as Hebrew words). Nomi had similar errors of conversion to the decimal structure in number comprehension (number-size comparison tasks), suggesting that her deficit is in a component shared by reading and comprehension. We also compared Nomi's number reading to her reading and signing of 406 Hebrew words. Nomi's word reading was in the high range of the normal performance of hearing controls and of deaf signers and significantly better than her multidigit number reading, demonstrating a dissociation between number reading, which was impaired, and word reading, which was spared. These results point to a specific type of dysnumeria in the number-frame generation for written multidigit numbers, whereby the conversion from written multidigit numbers to the abstract decimal structure is impaired, affecting both reading and comprehension. The results support abstract, non-verbal decimal structure generation that is shared by reading and comprehension, and also suggest the existence of a non-decimal number-reading route.
PubMed: 34267698
DOI: 10.3389/fpsyg.2021.649109 -
Frontiers in Psychology 2021Several studies have aimed to identify subtypes of dyscalculia. In many of these studies, either pre-defined groups (e.g., children with reading and mathematical...
Several studies have aimed to identify subtypes of dyscalculia. In many of these studies, either pre-defined groups (e.g., children with reading and mathematical difficulties vs. children with isolated mathematical difficulties) were analyzed regarding their cognitive profiles (top-down approach), or clusters of children with dyscalculia (CwD) were identified based on a narrow range of cognitive and mathematical skills (data-driven or bottom-up approach). However, it has remained difficult to establish robust subtypes of dyscalculia across studies. Against this background, we conducted a mixture model analysis in order to explore and identify subtypes of dyscalculia based on a broad range of variables (intelligence, reading fluency, working memory, attention, and various mathematical skills). The total sample comprised 174 elementary school CwD (IQ > 70; mathematical abilities: percentile rank <10), which consisted of two subsamples. The first subsample was based on a diagnostic test focusing on calculation (HRT 1-4; = 71; 46 girls, 25 boys; age: = 9.28 years, = 0.94) whereas the second subsample was based on a diagnostic test with a strong focus on basic numerical capacities (ZAREKI-R; = 103; 78 girls, 25 boys; age: = 8.94 years, = 1.05). Results provided convincing evidence for the existence of two subtypes in CwD: A slightly impaired subtype and a strongly impaired subtype. Subtypes differed most strongly regarding mathematical abilities, but the analyses suggest that differences in attention could also be a key factor. Therefore, comorbid attention difficulties seem to be a relevant factor that needs to be considered when establishing subtypes. Substantial intelligence differences between dyscalculia subtypes could not be found. Differences in working memory and reading fluency were negligible. Overall, the results seemed to be robust regardless of the diagnostic test used for assessing dyscalculia. When planning interventions for CwD, the existence of a subtype with substantial attention problems should be kept in mind.
PubMed: 34234706
DOI: 10.3389/fpsyg.2021.589506 -
Frontiers in Psychology 2021
PubMed: 34122263
DOI: 10.3389/fpsyg.2021.671771 -
Prion Dec 2021Swallowing function in long-term survivors of Creutzfeldt-Jakob disease (CJD) has not been elucidated. Herein, we report a patient with MM2-cortical-type sporadic CJD...
Swallowing function in long-term survivors of Creutzfeldt-Jakob disease (CJD) has not been elucidated. Herein, we report a patient with MM2-cortical-type sporadic CJD (MM2C-type sCJD) with long-term preservation of pharyngeal swallowing function using videofluoroscopic (VF) examination of swallowing. A 55-year-old woman was admitted to hospital because of dyscalculia and memory disturbance 3 years after the onset of these symptoms. Neurological examination revealed dementia, extrapyramidal signs, and delusion. Diffusion-weighted MRI revealed bilateral hyperintensity in the basal ganglia and frontal, temporal, and parietal cortices. No mutation with the methionine homozygote at codon 129 was found on PRNP gene analysis. VF was performed 68 months after the onset. Although bolus transport from the oral cavity to the pharynx worsened, the pharyngeal swallowing function was preserved even 68 months after onset. Serial MRI examinations revealed no apparent atrophy of the brainstem. Single photon emission computed tomography revealed that the regional cerebral blood flow in the brainstem was preserved. These findings suggest that pseudobulbar palsy is the pathophysiology underlying dysphagia in long-term survivors of MM2C-type sCJD, probably owing to preserved brainstem function even in a state of akinetic mutism.
Topics: Creutzfeldt-Jakob Syndrome; Deglutition; Diffusion Magnetic Resonance Imaging; Female; Humans; Middle Aged; Pharynx; Tomography, Emission-Computed, Single-Photon
PubMed: 34078217
DOI: 10.1080/19336896.2021.1930851 -
Brain Sciences May 2021Specific Learning Disorder (SLD) is a multifactorial, neurodevelopmental disorder which may involve persistent difficulties in reading (dyslexia), written expression... (Review)
Review
Specific Learning Disorder (SLD) is a multifactorial, neurodevelopmental disorder which may involve persistent difficulties in reading (dyslexia), written expression and/or mathematics. Dyslexia is characterized by difficulties with speed and accuracy of word reading, deficient decoding abilities, and poor spelling. Several studies from different, but complementary, scientific disciplines have investigated possible causal/risk factors for SLD. Biological, neurological, hereditary, cognitive, linguistic-phonological, developmental and environmental factors have been incriminated. Despite worldwide agreement that SLD is highly heritable, its exact biological basis remains elusive. We herein present: (a) an update of studies that have shaped our current knowledge on the disorder's genetic architecture; (b) a discussion on whether this genetic architecture is 'unique' to SLD or, alternatively, whether there is an underlying common genetic background with other neurodevelopmental disorders; and, (c) a brief discussion on whether we are at a position of generating meaningful correlations between genetic findings and anatomical data from neuroimaging studies or specific molecular/cellular pathways. We conclude with open research questions that could drive future research directions.
PubMed: 34068951
DOI: 10.3390/brainsci11050631 -
JMIR Serious Games May 2021Specific learning difficulties (SpLD) include several disorders such as dyslexia, dyscalculia, and dysgraphia, and the children with these SpLD receive special...
BACKGROUND
Specific learning difficulties (SpLD) include several disorders such as dyslexia, dyscalculia, and dysgraphia, and the children with these SpLD receive special education. However, the studies and the educational material so far focus mainly on one specific disorder.
OBJECTIVE
This study's primary goal is to develop comprehensive training material for different types of SpLD, with five serious games addressing different aspects of the SpLD. The second focus is measuring the impact of adaptive difficulty level adjustment in the children's and their educators' usability and technology acceptance perception. Receiving feedback from the children and their educators, and refining the games according to their suggestions have also been essential in this two-phase study.
METHODS
A total of 10 SpLD educators and 23 children with different types of SpLD tested the prototypes of the five serious games (ie, Word game, Memory game, Category game, Space game, and Math game), gave detailed feedback, answered the System Usability Scale and Technology Acceptance Model (TAM) questionnaires, and applied think-aloud protocols during game play.
RESULTS
The games' standard and adaptive versions were analyzed in terms of average playtime and the number of false answers. Detailed analyses of the interviews, with word clouds and player performances, were also provided. The TAM questionnaires' average and mean values and box plots of each data acquisition session for the children and the educators were also reported via System Usability Scale and TAM questionnaires. The TAM results of the educators had an average of 8.41 (SD 0.87) out of 10 in the first interview and an average of 8.71 (SD 0.64) out of 10 in the second interview. The children had an average of 9.07 (SD 0.56) out of 10 in the first interview.
CONCLUSIONS
Both the educators and the children with SpLD enjoyed playing the games, gave positive feedback, and suggested new ways for improvement. The results showed that these games provide thorough training material for different types of SpLD with personalized and tailored difficulty systems. The final version of the proposed games will become a part of the special education centers' supplementary curriculum and training materials, making new enhancements and improvements possible in the future.
PubMed: 34057415
DOI: 10.2196/25997