Search results for "Numerosity"
showing 10 items of 12 documents
Numbers and time doubly dissociate
2011
The magnitude dimensions of number, time and space have been suggested to share some common magnitude processing, which may imply symmetric interaction among dimensions. Here we challenge these suggestions by presenting a double dissociation between two neuropsychological patients with left (JT) and right (CB) parietal lesions and selective impairment of number and time processing respectively. Both patients showed an influence of task-irrelevant number stimuli on time but not space processing. In JT otherwise preserved time processing was severely impaired in the mere presence of task-irrelevant numbers, which themselves could not be processed accurately. In CB, impaired temporal estimatio…
Preschool Children’s Spontaneous Focusing on Numerosity, Subitizing, and Counting Skills as Predictors of Their Mathematical Performance Seven Years …
2015
This seven-year longitudinal study examined how children’s spontaneous focusing on numerosity (SFON), subitizing based enumeration, and counting skills assessed at five or six years predict their school mathematics achievement at 12 years. The participants were 36 Finnish children without diagnosed neurological disorders. The results, based on partial least squares modeling, demonstrate that SFON and verbal counting skills before school age predict mathematical performance on a standardized test for typical school mathematics in Grade 5. After controlling for nonverbal IQ, only SFON predict school mathematics. Subitizing-based enumeration skills have an indirect effect via number sequence s…
Preattentive and attentive responses to changes in small numerosities of tones in adult humans
2016
The brain hosts a primitive number sense to non-symbolically represent numerosities of objects or events. Small exact numerosities (~4 or less) can be individuated in parallel. In contrast, large numerosities (more than ~4) can only be approximated. However, whether small numerosities can be approximated without their parallel individuation remains unclear. Parallel individuation is suggested to be an attentive process and numerical approximation an automatic process. We, therefore, tested whether small numerosities can be represented preattentively. We recorded adult humans׳ event-related potentials (ERPs) and behavioral responses to 300-ms sequences of six tones (each of either 440 Hz or …
Cross-notational semantic priming between symbolic and nonsymbolic numerosity
2008
Symbolic and nonsymbolic numerosities produce similar behavioural effects and activate the same brain areas. These results have usually been interpreted in terms of a common, notation-independent magnitude representation. However, semantic priming between symbolic and nonsymbolic inputs has been somehow elusive (e.g., Koechlin, Naccache, Block, & Dehaene, 1999). In Experiment 1, we looked at whether cross-notational semantic priming depends on exact numerical meaning. Dice faces and digits were mixed as prime and target. Semantic priming occurred when prime and target were in the same notation as much as when they were in different notation. In Experiment 2, we found cross-notation sem…
Early mathematical skill profiles of prematurely and full-term born children
2017
Abstract Preterm birth is associated with low mathematical skills in children. This study on five-year-old Finnish children investigated whether mathematical skill profiles would differ between prematurely and full-term born children and how such profiles and other cognitive skills would be related. Mathematical skills included digit knowledge, spontaneous focusing on numerosity, arithmetic, counting and geometric skills. The investigated cognitive skills were phonological processing, working memory, instruction comprehension, speeded naming, inhibition and visuomotor skills. The participants were 119 preterm children with birth weight
Numerosity Discrimination in Children With Down Syndrome
2009
To understand the difficulties in mathematics exhibited by children with Down syndrome (DS), this study evaluated the core knowledge of numerosities with a discrimination task adapted from Xu and Spelke (2000). Although continuous variables varying with numerosity were controlled, children with DS discriminated the numerosity 8 from 16, but not from 12. Moreover, their performance did not differ from typically developing children matched either on chronological or mental age. Thus, the approximate numerosity system that recruits parietal lobes (Dehaene, Spelke, Pinel, Stanescu, & Tsivkin, 1999) is efficient in children with DS. These findings point at language-based systems as the source of…
Dissociations and interactions between time, numerosity and space processing
2009
AbstractThis study investigated time, numerosity and space processing in a patient (CB) with a right hemisphere lesion. We tested whether these magnitude dimensions share a common magnitude system or whether they are processed by dimension-specific magnitude systems. Five experimental tasks were used: Tasks 1–3 assessed time and numerosity independently and time and numerosity jointly. Tasks 4 and 5 investigated space processing independently and space and numbers jointly. Patient CB was impaired at estimating time and at discriminating between temporal intervals, his errors being underestimations. In contrast, his ability to process numbers and space was normal. A unidirectional interactio…
Quantity Estimation Based on Numerical Cues in the Mealworm Beetle (Tenebrio molitor)
2012
In this study, we used a biologically relevant experimental procedure to ask whether mealworm beetles (Tenebrio molitor) are spontaneously capable of assessing quantities based on numerical cues. Like other insect species, mealworm beetles adjust their reproductive behavior (i.e., investment in mate guarding) according to the perceived risk of sperm competition (i.e., probability that a female will mate with another male). To test whether males have the ability to estimate numerosity based on numerical cues, we staged matings between virgin females and virgin males in which we varied the number of rival males the experimental male had access to immediately preceding mating as a cue to sperm…
Impaired parietal magnitude processing in developmental dyscalculia
2007
Summary Developmental dyscalculia (DD) is a specific learning disability affecting the acquisition of school-level mathematical abilities in the context of otherwise normal academic achievement, with prevalence estimates in the order of 3–6% [1] . Behavioural studies show deficits in elementary numerical processing among individuals with pure DD [2,3], indicating that deficits in higher-level mathematical skills may stem from impaired representation and processing of basic numerical magnitude. Adult neuropsychological and neuroimaging research points to the intraparietal sulcus as a key region for the representation and processing of numerical magnitude [4]. This raises the possibility of a…
Are go/no-go tasks preferable to two-choice tasks in response time experiments with older adults?
2015
Epub ahead of print 02/11/2015 Recent research has shown that, in response time (RT) tasks, the go/no-go response procedure produces faster (and less noisy) RTs and fewer errors than the two-choice response procedure in children, although these differences are substantially smaller in college-aged adults. Here we examined whether the go/no-go procedure can be preferred to the two-choice procedure in RT experiments with older adults (i.e. another population with slower and more error-prone responding than college-aged individuals). To that end, we compared these response procedures in two experiments with older adults (Mage = 83 years): a visual word recognition task (lexical decision) and a…