Number transcoding in bilinguals—A transversal developmental study

in PLoS ONE (2022), 17(8), 0273391

Number transcoding is the cognitive task of converting between different numerical codes (i.e. visual “42”, verbal “forty-two”). Visual symbolic to verbal transcoding and vice versa strongly relies on ... [more ▼]

Number transcoding is the cognitive task of converting between different numerical codes (i.e. visual “42”, verbal “forty-two”). Visual symbolic to verbal transcoding and vice versa strongly relies on language proficiency. We evaluated transcoding of German-French bilinguals from Luxembourg in 5th, 8th, 11th graders and adults. In the Luxembourgish educational system, children acquire mathematics in German (LM1) until the 7th grade, and then the language of learning mathematic switches to French (LM2). French `70s `80s `90s are less transparent than `30s `40s `50s numbers, since they have a base-20 structure, which is not the case in German. Transcoding was evaluated with a reading aloud and a verbal-visual number matching task. Results of both tasks show a cognitive cost for transcoding numbers having a base-20 structure (i.e. `70s, `80s and `90s), such that response times were slower in all age groups. Furthermore, considering only base-10 numbers (i.e. `30s `40s `50s), it appeared that transcoding in LM2 (French) also entailed a cost. While participants across age groups tended to read numbers slower in LM2, this effect was limited to the youngest age group in the matching task. In addition, participants made more errors when reading LM2 numbers. In conclusion, we observed an age-independent language effect with numbers having a base-20 structure in French, reflecting their reduced transparency with respect to the decimal system. Moreover, we find an effect of language of math acquisition such that transcoding is less well mastered in LM2. This effect tended to persist until adulthood in the reading aloud task, while in the matching task performance both languages become similar in older adolescents and young adults. This study supports the link between numbers and language, especially highlighting the impact of language on reading numbers aloud from childhood to adulthood. [less ▲]

Automatic Integration of Numerical Formats Examined with Frequency-tagged EEG

in Scientific Reports (2021)

How humans integrate and abstract numerical information across different formats is one of the most debated questions in human cognition. We addressed the neuronal signatures of the numerical integration ... [more ▼]

How humans integrate and abstract numerical information across different formats is one of the most debated questions in human cognition. We addressed the neuronal signatures of the numerical integration using an EEG technique tagged at the frequency of visual stimulation. In an oddball design, participants were stimulated with standard sequences of numbers (<5) depicted in single (digits, dots, number words) or mixed notation (dots – digits, number words – dots, digits – number words), presented at 10Hz. Periodically, a deviant stimulus (>5) was inserted at 1.25 Hz. We observed significant oddball amplitudes for all single notations, showing for the first time using this EEG technique, that the magnitude information is spontaneously and unintentionally abstracted, irrespectively of the numerical format. Significant amplitudes were also observed for digits – number words and number words – dots, but not for digits – dots, suggesting an automatic integration across some numerical formats. These results imply that direct and indirect neuro-cognitive links exist across the different numerical formats. [less ▲]

Finger Rapid Automatized Naming (RAN) predicts the development of numerical representations better than finger gnosis

in Cognitive Development (2020), 53

When one-two-three beats two-one-three: Tracking the acquisition of the verbal number sequence.

in Psychonomic Bulletin and Review (2020), 27(1), 122-129

Learning how to count is a crucial step in cognitive development, which progressively allows for more elaborate numerical processing. The existing body of research consistently reports how children ... [more ▼]

Learning how to count is a crucial step in cognitive development, which progressively allows for more elaborate numerical processing. The existing body of research consistently reports how children associate the verbal code with exact quantity. However, the early acquisition of this code, when the verbal numbers are encoded in long-term memory as a sequence of words, has rarely been examined. Using an incidental assessment method based on serial recall of number words presented in ordered versus non-ordered sequences (e.g., one-two-three vs. two-one-three), we tracked the progressive acquisition of the verbal number sequence in children aged 3-6 years. Results revealed evidence for verbal number sequence knowledge in the youngest children even before counting is fully mastered. Verbal numerical knowledge thus starts to be organized as a sequence in long-term memory already at the age of 3 years, and this numerical sequence knowledge is assessed in a sensitive manner by incidental rather than explicit measures of number knowledge. [less ▲]

The neural signature of numerosity by separating numerical and continuous magnitude extraction in visual cortex with frequency-tagged EEG.

in Proceedings of the National Academy of Sciences of the United States of America (2020), 117(11), 5726-5732

The ability to handle approximate quantities, or number sense, has been recurrently linked to mathematical skills, although the nature of the mechanism allowing to extract numerical information (i.e ... [more ▼]

The ability to handle approximate quantities, or number sense, has been recurrently linked to mathematical skills, although the nature of the mechanism allowing to extract numerical information (i.e., numerosity) from environmental stimuli is still debated. A set of objects is indeed not only characterized by its numerosity but also by other features, such as the summed area occupied by the elements, which often covary with numerosity. These intrinsic relations between numerosity and nonnumerical magnitudes led some authors to argue that numerosity is not independently processed but extracted through a weighting of continuous magnitudes. This view cannot be properly tested through classic behavioral and neuroimaging approaches due to these intrinsic correlations. The current study used a frequency-tagging EEG approach to separately measure responses to numerosity as well as to continuous magnitudes. We recorded occipital responses to numerosity, total area, and convex hull changes but not to density and dot size. We additionally applied a model predicting primary visual cortex responses to the set of stimuli. The model output was closely aligned with our electrophysiological data, since it predicted discrimination only for numerosity, total area, and convex hull. Our findings thus demonstrate that numerosity can be independently processed at an early stage in the visual cortex, even when completely isolated from other magnitude changes. The similar implicit discrimination for numerosity as for some continuous magnitudes, which correspond to basic visual percepts, shows that both can be extracted independently, hence substantiating the nature of numerosity as a primary feature of the visual scene. [less ▲]

Mental arithmetic in the bilingual brain: Language matters.

in Neuropsychologia (2017), 101

How do bilinguals solve arithmetic problems in each of their languages? We investigated this question by exploring the neural substrates of mental arithmetic in bilinguals. Critically, our population was ... [more ▼]

How do bilinguals solve arithmetic problems in each of their languages? We investigated this question by exploring the neural substrates of mental arithmetic in bilinguals. Critically, our population was composed of a homogeneous group of adults who were fluent in both of their instruction languages (i.e., German as first instruction language and French as second instruction language). Twenty bilinguals were scanned with fMRI (3T) while performing mental arithmetic. Both simple and complex problems were presented to disentangle memory retrieval occuring in very simple problems from arithmetic computation occuring in more complex problems. In simple additions, the left temporal regions were more activated in German than in French, whereas no brain regions showed additional activity in the reverse constrast. Complex additions revealed the reverse pattern, since the activations of regions for French surpassed the same computations in German and the extra regions were located predominantly in occipital regions. Our results thus highlight that highly proficient bilinguals rely on differential activation patterns to solve simple and complex additions in each of their languages, suggesting different solving procedures. The present study confirms the critical role of language in arithmetic problem solving and provides novel insights into how highly proficient bilinguals solve arithmetic problems. [less ▲]

Sixty-twelve = Seventy-two? A cross-linguistic comparison of children's number transcoding.

in The British journal of developmental psychology (2016), 34(3), 461-8

We compared French- and English-speaking fifth-grade (10-year-old) children's performance in number transcoding. Whereas English two-digit number names follow the decimal structure (base 10), the ... [more ▼]

We compared French- and English-speaking fifth-grade (10-year-old) children's performance in number transcoding. Whereas English two-digit number names follow the decimal structure (base 10), the structure of French two-digit number words over 60 follow a vigesimal structure (base 20). Children undertook two number transcoding tasks. While children were generally successful at the tasks, English-speaking children significantly outperformed French-speaking children for numbers following a vigesimal structure in French compared to a decimal structure in English (i.e., numbers >60). Our findings show that verbal number name structures influence children's performance in numerical tasks, even though fifth-grade children have well passed the initial stage of acquiring transcoding skills for two-digit numbers. These findings highlight the importance of language specificities in children's number transcoding. Statement of contribution What is already known? Previous research reports that language influences number processing in young children. Number transcoding performances can be conditioned by the linguistic structure of number words. What does this study add? Our results show how the structure of French vigesimal number words impacts number transcoding. They demonstrate that these language influences also affect children who already master basic number competencies. [less ▲]

How does Language influence Number transcoding?

Poster (2015, September 29)

The German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent with respect to the Arabic number code. The linguistic ... [more ▼]

The German number word system inverts units and tens compared to the Arabic notation. This is not the case in French, which is more transparent with respect to the Arabic number code. The linguistic structure of number words can facilitate or impede numerical development and performances in number transcoding tasks. We used an original transcoding paradigm with 4th grade French-speaking children, 4th grade German-speaking children, as well as French-speaking and German-speaking young adults who listened to two-digit numbers and had to identify the heard number among four visually presented Arabic numbers. The novelty of our paradigm consisted in manipulating the order of appearance of the units and tens of the Arabic numbers, leading to three conditions: units-first, tens-first and simultaneous appearance. Results revealed that German-speaking children were globally slower than their French-speaking peers. In contrast, language did not affect overall transcoding speed in young adults. Moreover children from both language groups were faster in transcoding when the order of digit appearance was congruent with the number word system (i.e. units-first in German and tens-first in French) compared to the incongruent and the simultaneous presentation order. This pattern indicates that children tended to process number sequentially during the transcoding task. This pattern differed from the behavior observed in adult, since both German- and French-speaking adults solved the transcoding task faster when tens were presented before units (i.e. tens-first) than the reverse. [less ▲]