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Deutsches Arzteblatt International Feb 20193-7% of all children, adolescents, and adults suffer from dyscalculia. Severe, persistent difficulty performing arithmetical calculations leads to marked impairment in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
3-7% of all children, adolescents, and adults suffer from dyscalculia. Severe, persistent difficulty performing arithmetical calculations leads to marked impairment in school, at work, and in everyday life and elevates the risk of comorbid mental disorders. The state of the evidence underlying various methods of diagnosing and treating this condition is unclear.
METHODS
Systematic literature searches were carried out from April 2015 to June 2016 in the PsycInfo, PSYNDEX, MEDLINE, ProQuest, ERIC, Cochrane Library, ICTRP, and MathEduc databases. The main search terms on dyscalculia were the German terms "Rechenstörung," "Rechenschwäche," and "Dyskalkulie" and the English terms "dyscalculia," "math disorder, and "math disability." The data from the retrieved studies were evaluated in a meta-analysis, and corresponding recommendations on the diagnosis and treatment of dyscalculia were jointly issued by the 20 societies and associations that participated in the creation of this guideline.
RESULTS
The diagnosis of dyscalculia should only be made if the person in question displays below-average mathematical performance when seen in the context of relevant information from the individual history, test findings, clinical examination, and further psychosocial assessment. The treatment should be directed toward the individual mathematical problem areas. The mean effect size found across all intervention trials was 0.52 (95% confidence interval [0.42; 0.62]). Treatment should be initiated early on in the primary-school years and carried out by trained specialists in an individual setting; comorbid symptoms and disorders should also receive attention. Persons with dyscalculia are at elevated risk of having dyslexia as well (odds ratio [OR]: 12.25); the same holds for attention deficit/hyperactivity disorder and for other mental disorders, both internalizing (such as anxiety and depression) and externalizing (e.g., disorders characterized by aggression and rule-breaking).
CONCLUSION
Symptom-specific interventions involving the training of specific mathematical content yield the best results. There is still a need for high-quality intervention trials and for suitable tests and learning programs for older adolescents and adults.
Topics: Dyscalculia; Humans
PubMed: 30905334
DOI: 10.3238/arztebl.2019.0107 -
European Journal of Pediatrics Jan 2015Numerical skills are essential in our everyday life, and impairments in the development of number processing and calculation have a negative impact on schooling and... (Review)
Review
UNLABELLED
Numerical skills are essential in our everyday life, and impairments in the development of number processing and calculation have a negative impact on schooling and professional careers. Approximately 3 to 6 % of children are affected from specific disorders of numerical understanding (developmental dyscalculia (DD)). Impaired development of number processing skills in these children is characterized by problems in various aspects of numeracy as well as alterations of brain activation and brain structure. Moreover, DD is assumed to be a very heterogeneous disorder putting special challenges to define homogeneous diagnostic criteria. Finally, interdisciplinary perspectives from psychology, neuroscience and education can contribute to the design for interventions, and although results are still sparse, they are promising and have shown positive effects on behaviour as well as brain function.
CONCLUSION
In the current review, we are going to give an overview about typical and atypical development of numerical abilities at the behavioural and neuronal level. Furthermore, current status and obstacles in the definition and diagnostics of DD are discussed, and finally, relevant points that should be considered to make an intervention as successful as possible are summarized.
Topics: Brain; Child; Developmental Disabilities; Dyscalculia; Humans; Mathematical Concepts; Neuropsychological Tests
PubMed: 25529864
DOI: 10.1007/s00431-014-2455-7 -
Pediatric Neurology May 2001Developmental dyscalculia is a specific learning disability affecting the acquisition of arithmetic skills in an otherwise-normal child. Although poor teaching,... (Review)
Review
Developmental dyscalculia is a specific learning disability affecting the acquisition of arithmetic skills in an otherwise-normal child. Although poor teaching, environmental deprivation, and low intelligence have been implicated in the etiology of developmental dyscalculia, current data indicate that this learning disability is a brain-based disorder with a familial-genetic predisposition. The neurologic substrate of developmental dyscalculia is thought to involve both hemispheres, particularly the left parietotemporal areas. Developmental dyscalculia is a common cognitive handicap; its prevalence in the school population is about 5-6%, a frequency similar to those of developmental dyslexia and attention-deficit-hyperactivity disorder. Unlike these, however, it is as common in females as in males. Developmental dyscalculia frequently is encountered in neurologic disorders, examples of which include attention-deficit-hyperactivity disorder, developmental language disorder, epilepsy, and fragile X syndrome. The long-term prognosis of developmental dyscalculia is unknown; it appears, however, to persist, at least for the short-term, in about half of affected preteen children. The consequences of developmental dyscalculia and its impact on education, employment, and psychologic well-being of affected individuals are unknown.
Topics: Brain Damage, Chronic; Cerebral Cortex; Humans; Learning Disabilities; Mathematics; Physician's Role; Prognosis
PubMed: 11516606
DOI: 10.1016/s0887-8994(00)00258-7 -
Handbook of Clinical Neurology 2013Developmental dyscalculia (DD) is a learning disorder affecting the acquisition of school level arithmetic skills present in approximately 3-6% of the population. At the... (Review)
Review
Developmental dyscalculia (DD) is a learning disorder affecting the acquisition of school level arithmetic skills present in approximately 3-6% of the population. At the behavioral level DD is characterized by poor retrieval of arithmetic facts from memory, the use of immature calculation procedures and counting strategies, and the atypical representation and processing of numerical magnitude. At the neural level emerging evidence suggests DD is associated with atypical structure and function in brain regions associated with the representation of numerical magnitude. The current state of knowledge points to a core deficit in numerical magnitude representation in DD, but further work is required to elucidate causal mechanisms underlying the disorder.
Topics: Brain; Dyscalculia; Humans; Neuroimaging
PubMed: 23622170
DOI: 10.1016/B978-0-444-52891-9.00025-7 -
Handbook of Clinical Neurology 2020Developmental dyscalculia (DD) is a developmental learning disability that manifests as a persistent difficulty in comprehending even the most basic numeric and... (Review)
Review
Developmental dyscalculia (DD) is a developmental learning disability that manifests as a persistent difficulty in comprehending even the most basic numeric and arithmetic concepts, despite normal intelligence and schooling opportunities. Given the predominant use of numbers in modern society, this condition can pose major challenges in the sufferer's everyday life, both in personal and professional development. Since, to date, we still lack a universally recognized and psychometrically driven definition of DD, its diagnosis has been applied to a wide variety of cognitive profiles. In this chapter, we review the behavioral and neural characterization of DD as well as the different neurocognitive and etiologic accounts of this neurodevelopmental disorder. We underline the multicomponential nature of this heterogeneous disability: different aspects of mathematical competence can be affected by both the suboptimal recruitment of general cognitive functions supporting mathematical cognition (such as attention, memory, and cognitive control) and specific deficits in mastering numeric concepts and operations. Accordingly, both intervention paradigms focused on core numeric abilities and more comprehensive protocols targeting multiple neurocognitive systems have provided evidence for effective positive outcomes.
Topics: Attention; Cognition; Developmental Disabilities; Dyscalculia; Humans; Memory
PubMed: 32977896
DOI: 10.1016/B978-0-444-64148-9.00005-3 -
Applied Neuropsychology. Child 2022The study of dyscalculia requires an analysis of the current developed hypotheses which describe the cognitive mechanisms involved in this neurodevelopmental disorder.... (Review)
Review
The study of dyscalculia requires an analysis of the current developed hypotheses which describe the cognitive mechanisms involved in this neurodevelopmental disorder. The objective of our review is to determine any progress in modeling developmental dyscalculia. The first hypothesis suggests that dyscalculia is the consequence of a specific deficit level number on the precise number system and the approximate system. Then, the second hypothesis states that developmental dyscalculia is linked to a failure to process non-symbolic representations of numbers. On the other hand, the third suggests that dyscalculia is caused by a lack of access to numerical quantities from symbols. However, the last hypothesis asserts that developmental dyscalculia is linked to general deficits. All these hypotheses are compatible with recent neuroimaging results and raise new horizons for experimentation, which will allow the development of precise diagnostic tools and the improvement of intervention strategies and the remediation of developmental dyscalculia.
Topics: Child; Cognition; Cognition Disorders; Developmental Disabilities; Dyscalculia; Humans; Mathematics
PubMed: 34320331
DOI: 10.1080/21622965.2021.1955679 -
Developmental Medicine and Child... Apr 1991
Review
Topics: Brain Damage, Chronic; Child; Child Development; Child, Preschool; Concept Formation; Humans; Learning Disabilities; Mathematics; Problem Solving; Syndrome
PubMed: 2044857
DOI: 10.1111/j.1469-8749.1991.tb14888.x -
Pediatric Neurology Aug 2016Dyscalculia, like dyslexia, affects some 5% of school-age children but has received much less investigative attention. In two thirds of affected children, dyscalculia is... (Review)
Review
Dyscalculia, like dyslexia, affects some 5% of school-age children but has received much less investigative attention. In two thirds of affected children, dyscalculia is associated with another developmental disorder like dyslexia, attention-deficit disorder, anxiety disorder, visual and spatial disorder, or cultural deprivation. Infants, primates, some birds, and other animals are born with the innate ability, called subitizing, to tell at a glance whether small sets of scattered dots or other items differ by one or more item. This nonverbal approximate number system extends mostly to single digit sets as visual discrimination drops logarithmically to "many" with increasing numerosity (size effect) and crowding (distance effect). Preschoolers need several years and specific teaching to learn verbal names and visual symbols for numbers and school agers to understand their cardinality and ordinality and the invariance of their sequence (arithmetic number line) that enables calculation. This arithmetic linear line differs drastically from the nonlinear approximate number system mental number line that parallels the individual number-tuned neurons in the intraparietal sulcus in monkeys and overlying scalp distribution of discrete functional magnetic resonance imaging activations by number tasks in man. Calculation is a complex skill that activates both visual and spatial and visual and verbal networks. It is less strongly left lateralized than language, with approximate number system activation somewhat more right sided and exact number and arithmetic activation more left sided. Maturation and increasing number skill decrease associated widespread non-numerical brain activations that persist in some individuals with dyscalculia, which has no single, universal neurological cause or underlying mechanism in all affected individuals.
Topics: Animals; Brain; Dyscalculia; Humans; Mathematical Concepts
PubMed: 27515455
DOI: 10.1016/j.pediatrneurol.2016.02.007 -
Journal of Child Neurology Oct 2004Developmental dyscalculia is a specific learning disability affecting the normal acquisition of arithmetic skills. Genetic, neurobiologic, and epidemiologic evidence... (Review)
Review
Developmental dyscalculia is a specific learning disability affecting the normal acquisition of arithmetic skills. Genetic, neurobiologic, and epidemiologic evidence indicates that dyscalculia, like other learning disabilities, is a brain-based disorder. However, poor teaching and environmental deprivation have also been implicated in its etiology. Because the neural network of both hemispheres comprises the substrate of normal arithmetic skills, dyscalculia can result from dysfunction of either hemisphere, although the left parietotemporal area is of particular significance. The prevalence of developmental dyscalculia is 5 to 6% in the school-aged population and is as common in girls as in boys. Dyscalculia can occur as a consequence of prematurity and low birthweight and is frequently encountered in a variety of neurologic disorders, such as attention-deficit hyperactivity disorder (ADHD), developmental language disorder, epilepsy, and fragile X syndrome. Developmental dyscalculia has proven to be a persisting learning disability, at least for the short term, in about half of affected preteen pupils. Educational interventions for dyscalculia range from rote learning of arithmetic facts to developing strategies for solving arithmetic exercises. The long-term prognosis of dyscalculia and the role of remediation in its outcome are yet to be determined.
Topics: Adolescent; Child; Female; Humans; Learning Disabilities; Male; Mathematics; Models, Psychological; Problem Solving; Prognosis
PubMed: 15559892
DOI: 10.1177/08830738040190100601 -
Neuropsychology Review Dec 2002Even though it is generally recognized that calculation ability represents a most important type of cognition, there is a significant paucity in the study of acalculia.... (Review)
Review
Even though it is generally recognized that calculation ability represents a most important type of cognition, there is a significant paucity in the study of acalculia. In this paper the historical evolution of calculation abilities in humankind and the appearance of numerical concepts in child development are reviewed. Developmental calculation disturbances (developmental dyscalculia) are analyzed. It is proposed that calculation ability represents a multifactor skill, including verbal, spatial, memory, body knowledge, and executive function abilities. A general distinction between primary and secondary acalculias is presented, and different types of acquired calculation disturbances are analyzed. The association between acalculia and aphasia, apraxia and dementia is further considered, and special mention to the so-called Gerstmann syndrome is made. A model for the neuropsychological assessment of numerical abilities is proposed, and some general guidelines for the rehabilitation of calculation disturbances are presented.
Topics: Animals; Aphasia; Apraxias; Cognition Disorders; Dementia; Female; Gerstmann Syndrome; History, 20th Century; History, 21st Century; Humans; Learning Disabilities; Male; Mathematics; Neuropsychological Tests; Sex Factors
PubMed: 12539968
DOI: 10.1023/a:1021343508573