A developmental model of number representation

We delineate a developmental model of number representations. Notably, developmental dyscalculia (DD) is rarely associated with an all-or-none deficit in numerosity processing as would be expected if assuming abstract number representations. Finally, we suggest that the "generalist genes” view might be a plausible - though thus far speculative - explanatory framework for our model of how number representations develo

The synthesis of a novel diazo-diphosphetidine-diamine based on interaction of 2-amino-4-phenylthiazole with chloride phosphorus(III)

In recent years, the obtaining and study of structural features of organophosphorus heterocyclic compounds with P-N bond, attracted considerable attention. Heterocycles which contain P-C, P-N, P-O and P-S bonds have a high biological activity and commercial importance. In this work, we have studied the reaction of interaction 2-amino-4-phenylthiazole with. phosphorus trichloride The conditions of reaction and structure of the resulting compounds were found

Developmental dyscalculia in adults: Current issues and open questions for future research.

Developmental dyscalculia (DD) is a chronic condition that poses not only a barrier to employment and socio-emotional wellbeing but that also persists into adulthood. Thus, understanding the neuro-cognitive foundations of DD is relevant for both children and adults with DD. However, so far the vast majority of scientific research endeavours has been dedicated to the study of DD in children only. Consequently, our current understanding of DD in adulthood is rather patchy. The main aim of the present review is to summarize the scientific findings on DD in adults by focusing on its cognitive manifestations and neural substrates in adults. For instance, research on DD in adulthood suggests that – beyond an outstanding deficiency in number processing – the processing of non-numerical magnitudes and domain-general skills seem to be also impaired in adults suffering from persistent DD. A secondary aim of this review is to delineate future lines of research that will provide us with a more elaborate understanding of the neurocognitive underpinnings of DD in adults (thus fostering the development of sensitive diagnostic marker tasks), and to formulate potential intervention areas targeting deficiencies frequently characterizing DD in adults

Developmental dyscalculia: compensatory mechanisms in left intraparietal regions in response to nonsymbolic magnitudes

BACKGROUND: Functional magnetic resonance imaging (fMRI) studies investigating the neural mechanisms underlying developmental dyscalculia are scarce and results are thus far inconclusive. Main aim of the present study is to investigate the neural correlates of nonsymbolic number magnitude processing in children with and without dyscalculia. METHODS: 18 children (9 with dyscalculia) were asked to solve a non-symbolic number magnitude comparison task (finger patterns) during brain scanning. For the spatial control task identical stimuli were employed, instructions varying only (judgment of palm rotation). This design enabled us to present identical stimuli with identical visual processing requirements in the experimental and the control task. Moreover, because numerical and spatial processing relies on parietal brain regions, task-specific contrasts are expected to reveal true number-specific activations. RESULTS: Behavioral results during scanning reveal that despite comparable (almost at ceiling) performance levels, task-specific activations were stronger in dyscalculic children in inferior parietal cortices bilaterally (intraparietal sulcus, supramarginal gyrus, extending to left angular gyrus). Interestingly, fMRI signal strengths reflected a group x task interaction: relative to baseline, controls produced significant deactivations in (intra)parietal regions bilaterally in response to number but not spatial processing, while the opposite pattern emerged in dyscalculics. Moreover, beta weights in response to number processing differed significantly between groups in left - but not right - (intra)parietal regions (becoming even positive in dyscalculic children). CONCLUSION: Overall, findings are suggestive of (a) less consistent neural activity in right (intra)parietal regions upon processing nonsymbolic number magnitudes; and (b) compensatory neural activity in left (intra)parietal regions in developmental dyscalculia.(VLID)218888

Impaired Arithmetic Fact Retrieval in an Adult with Developmental Dyscalculia: Evidence from Behavioral and Functional Brain Imaging Data

Developmental dyscalculia (DD) is a developmental disorder characterized by arithmetic difficulties. Recently, it has been suggested that the neural networks supporting procedure-based calculation (e.g., in subtraction) and left-hemispheric verbal arithmetic fact retrieval (e.g., in multiplication) are partially distinct. Here we compared the neurofunctional correlates of subtraction and multiplication in a 19-year-old student (RM) with DD to 18 age-matched controls. Behaviorally, RM performed significantly worse than controls in multiplication, while subtraction was unaffected. Neurofunctional differences were most pronounced regarding multiplication: RM showed significantly stronger activation than controls not only in left angular gyrus but also in a fronto-parietal network (including left intraparietal sulcus and inferior frontal gyrus) typically activated during procedure-based calculation. Region-of-interest analyses indicated group differences in multiplication only, which, however, did not survive correction for multiple comparisons. Our results are consistent with dissociable and processing-specific, but not operation-specific neurofunctional networks. Procedure-based calculation is not only associated with subtraction but also with (untrained) multiplication facts. Only after rote learning, facts can be retrieved quasi automatically from memory. We suggest that this learning process and the associated shift in activation patterns has not fully occurred in RM, as reflected in her need to resort to procedure-based strategies to solve multiplication facts

Partizipation von Studierenden mit neurokognitiven Beeinträchtigungen am Beispiel von ADHS und spezifischen Lernstörungen

Zusammenfassung: Das Hauptziel des vorliegenden Beitrags ist eine kritische Reflexion der Situation von Studierenden mit neurokognitiven Beeinträchtigungen in Hinblick auf deren Partizipation im universitären Setting. Nach einer kurzen Erläuterung der aktuellen universitätsrechtlichen Rahmenbedingungen in Deutschland, Österreich und der Schweiz werden (i) am Beispiel von Aufmerksamkeitsstörungen und spezifischen Lernstörungen charakteristische Schwierigkeiten von betroffenen Studierenden beim Studium anhand von Fallvignetten dargestellt und (ii) Ziele in Hinblick auf eine gelingende Partizipation und Chancengleichheit für Studierende mit Beeinträchtigungen skizziert. Anhand eines tentativen Rahmenmodells zur Förderung der Partizipation diskutieren wir die Notwendigkeit differenzierter universitätsinterner und -externer struktureller Rahmenbedingungen, die zusätzlich zu den bereits bestehenden – aber nicht ausreichenden – universitätsinternen Maßnahmen wie dem Nachteilsausgleich implementiert werden sollten. Participation of University Students with Neurocognitive Deficiencies: Evidence from ADHD and Specific Learning Disorders Abstract: This paper critically reflects on the current situation of students with neurocognitive deficiencies regarding their participation in the academic setting. After providing a brief summary of the relevant judicial frameworks implemented at universities in Germany, Austria, and Switzerland, we (1) present single-case histories to delineate characteristic difficulties encountered by students with attention and/or specific learning disorders; and (2) formulate a desirable target state regarding successful participation and equal opportunities for students with neurocognitive deficiencies. We suggest a tentative model targeted at fostering students’ participation and discuss the necessity to provide effective basic parameters at different levels both within and outside the academic setting which go beyond the currently offered disadvantage compensation