Einleitung: Lernstörungen im multilingualen Kontext – Eine Herausforderung

in Ugen, Sonja; Schiltz, Christine; Fischbach, Antoine (Eds.) et al Lernstörungen im multilingualen Kontext: Diagnose und Hilfestellungen (2021)

Harmonic amplitude summation for frequency-tagging analysis

in Journal of Cognitive Neuroscience (2021)

In the approach of frequency tagging, stimuli that are presented periodically generate periodic responses of the brain. Following a transformation into the frequency domain, the brain’s response is often ... [more ▼]

In the approach of frequency tagging, stimuli that are presented periodically generate periodic responses of the brain. Following a transformation into the frequency domain, the brain’s response is often evident at the frequency of stimulation, F, and its higher harmonics (2F, 3F, etc.). This approach is increasingly used in neuroscience, as it affords objective measures to characterize brain function. However, whether these specific harmonic frequency responses should be combined for analysis, and if so, how, remains an outstanding issue. In most studies, higher harmonic responses have not been described or were described only individually; in other studies, harmonics have been combined with various approaches, e.g., averaging and root mean squared summation. A rationale for these approaches in the context of frequency-based analysis principles, and understanding of how they relate to the brain’s response amplitudes in the time domain, has been missing. Here, with these elements addressed, the summation of (baseline-corrected) harmonic amplitude is recommended. [less ▲]

Identifying Math and Reading Difficulties of Multilingual Children: Effects of Different Cut-offs and Reference Groups

in Herzog, Moritz; Gürsoy, Erkan; Fritz-Stratmann, Annemarie (Eds.) Diversity Dimensions in Mathematics and Language Learning. Perspectives on culture, education, and multilingualism (2021)

Extensive research is available on language acquisition and the acquisition of mathematical skills in early childhood. But more recently, research has turned to the question of the influence of specific ... [more ▼]

Extensive research is available on language acquisition and the acquisition of mathematical skills in early childhood. But more recently, research has turned to the question of the influence of specific language aspects on acquisition of mathematical skills. This anthology combines current findings and theories from various disciplines such as (neuro-)psychology, linguistics, didactics and anthropology. [less ▲]

Cognitive cost of two- and single digit transcoding in the second language of math learning in bilinguals of different ages

Scientific Conference (2020, June)

Impact of learning to read in a mixed approach on neural tuning to words in beginning readers

in Frontiers in Psychology (2020), 10

The impact of learning to read in a mixed approach using both the global and phonics teaching methods on the emergence of left hemisphere neural specialization for word recognition is yet unknown in ... [more ▼]

The impact of learning to read in a mixed approach using both the global and phonics teaching methods on the emergence of left hemisphere neural specialization for word recognition is yet unknown in children. Taking advantage of a natural school context with such a mixed approach, we tested 42 first graders behaviorally and with Fast Periodic Visual Stimulation using electroencephalographic recordings (FPVS-EEG) to measure selective neural responses to letter strings. Letter strings were inserted periodically (1/5) in pseudofonts in 40 s sequences displayed at 6 Hz and were either words globally taught at school, that could therefore be processed by visual whole-word form recognition (global method), or control words/pseudowords eliciting graphemephoneme (GP) mappings (phonics method). Results show that selective responses (F/5, 1.2 Hz) were left lateralized for control stimuli that triggered GP mappings but bilateral for globally taught words. It implies that neural mechanisms recruited during visual word processing are influenced by the nature of the mapping between written and spoken word forms. GP mappings induce left hemisphere discrimination responses, and visual recognition of whole-word forms induce bilateral responses, probably because the right hemisphere is relatively more involved in holistic visual object recognition. Splitting the group as a function of the mastery of GP mappings into “good” and “poor” readers strongly suggests that good readers actually processed all stimuli (including global words) predominantly with their left hemisphere, while poor readers showed bilateral responses for global words. These results show that in a mixed approach of teaching to read, global method instruction may induce neural processes that differ from those specialized for reading in the left hemisphere. Furthermore, given their difficulties in automatizing GP mappings, poor readers are especially prone to rely on this alternative visual strategy. A preprint of this paper has been released on Biorxiv (van de Walle de Ghelcke et al., 2018). [less ▲]

A robust electrophysiological marker of spontaneous numerical discrimination

in Scientific Reports (2020)

Developmental changes in neural letter-selectivity: A 1-year follow-up of beginning readers.

in Developmental science (2020)

The developmental course of neural tuning to visual letter strings is unclear. Here we tested 39 children longitudinally, at the beginning of grade 1 (6.45 ± 0.33 years old) and 1 year after, with fast ... [more ▼]

The developmental course of neural tuning to visual letter strings is unclear. Here we tested 39 children longitudinally, at the beginning of grade 1 (6.45 ± 0.33 years old) and 1 year after, with fast periodic visual stimulation in electroencephalography to assess the evolution of selective neural responses to letter strings and their relationship with emerging reading abilities. At both grades, frequency-tagged letter strings were discriminated from pseudofont strings (i.e. letter-selectivity) over the left occipito-temporal cortex, with effects observed at the individual level in 62% of children. However, visual words were not discriminated from pseudowords (lexical access) at either grade. Following 1 year of schooling, letter-selective responses showed a specific increase in amplitude, a more complex pattern of harmonics, and were located more anteriorly over the left occipito-temporal cortex. Remarkably, at both grades, neural responses were highly significant at the individual level and correlated with individual reading scores. The amplitude increase in letter-selective responses between grades was not found for discrimination responses of familiar keyboard symbols from pseudosymbols, and was not related to a general increase in visual stimulation responses. These findings demonstrate a rapid onset of left hemispheric letter selectivity, with 1 year of reading instruction resulting in increased emerging reading abilities and a clear quantitative and qualitative evolution within left hemispheric neural circuits for reading. [less ▲]

NASCO: A New Method and Program to Generate Dot Arrays for Non-Symbolic Number Comparison Tasks

in Journal of Numerical Cognition (2020), 6(1), 129--147

Basic numerical abilities are generally assumed to influence more complex cognitive processes involving numbers, such as mathematics. Yet measuring non-symbolic number abilities remains challenging due to ... [more ▼]

Basic numerical abilities are generally assumed to influence more complex cognitive processes involving numbers, such as mathematics. Yet measuring non-symbolic number abilities remains challenging due to the intrinsic correlation between numerical and non-numerical dimensions of any visual scene. Several methods have been developed to generate non-symbolic stimuli controlling for the latter aspects but they tend to be difficult to replicate or implement. In this study, we describe the NASCO method, which is an extension to the method popularized by Dehaene, Izard, and Piazza (2005). Their procedure originally controlled for two visual dimensions that are mediated by Number: Total Area and Item Size (i.e., N = TA/IS). Here, we additionally propose to control for another twofold dimension related to the array extent, which is also mediated by Number: Convex Hull Area and Mean Occupancy (i.e., N = CH/MO). We illustrate the NASCO method with a MATLAB app—NASCO app—that allows easy generation of dot arrays for a visually controlled assessment of non-symbolic numerical abilities. Results from a numerical comparison task revealed that the introduction of this twofold dimension manipulation substantially affected young adults’ performance. In particular, we did not replicate the relation between non-symbolic number abilities and arithmetic skills. Our findings open the debate about the reliability of previous results that did not take into account visual features related to the array extent. We then discuss the strengths of NASCO method to assess numerical ability, as well as the benefits of its straightforward implementation in NASCO app for researchers. [less ▲]

The effect of grade retention on reading skills of immigrant children in multilingual elementary school. A longitudinal study.

Presentation (2019, November 06)

In a longitudinal study the effect of grade retention on reading skills of immigrant children in multilingual elementary school was investigated. The study was conducted between 2013 and 2017 and thirty ... [more ▼]

In a longitudinal study the effect of grade retention on reading skills of immigrant children in multilingual elementary school was investigated. The study was conducted between 2013 and 2017 and thirty-four per cent of the sample was lost due to grade retention. These children had been followed from kindergarten to grade 3 of elementary school. To observe differences among promoted and retained students, we assessed them using various language and socioeconomic measures. We also compared a subgroup of promoted students, scoring lower in grade 2 than the mean of retained students in reading comprehension. The current study revealed four main findings. Firstly, there were no significant differences between promoted and retained students in their first language vocabulary (Portuguese). Secondly, there was a significant difference in second and third language vocabularies (Luxembourgish and German) and in German reading tasks (the language of instruction) from kindergarten to grade 2, with promoted students scoring higher than retained students. Thirdly, and most importantly, retained students did not catch up with promoted students in the language of instruction (German) measures even after grade retention, but they did in language of socialisation (Luxembourgish). Fourthly, and in contrast to retained students, the low-achieving promoted students improved significantly in German reading comprehension by grade 3.The last two findings underline that grade retention does not lead to improvement in children’s reading comprehension. As vocabulary is one of the main predictors of reading comprehension, programs that improve poor readers’ vocabulary knowledge may be more efficient than grade retention. The present findings corroborate previous studies reporting that grade retention is not beneficial and that low-achieving students promoted to the next grade show better academic outcomes later than retained students. [less ▲]

Weaker neural responses to lexicality and word frequency in dyslexic adults: an EEG study with Fast Periodic Visual Stimulation.

Scientific Conference (2019, September)

Dyslexia, a persistent reading disorder, is characterized by different brain activation patterns when reading. Here, we used a Fast Periodic Visual Stimulation paradigm during EEG recordings to assess the ... [more ▼]

Dyslexia, a persistent reading disorder, is characterized by different brain activation patterns when reading. Here, we used a Fast Periodic Visual Stimulation paradigm during EEG recordings to assess the sensitivity of dyslexics to fine-grained psycholinguistic variations of letter strings: lexicality, lexical frequency, and orthographic regularity. Dyslexic and non-dyslexic students watched 60-seconds streams of stimuli presented at 10Hz, in which deviant items are inserted periodically (1/8, at 1.25Hz). Results show discrimination responses at 1.25Hz over left posterior occipito-temporal regions, reduced in dyslexics. Group differences were significant for discrimination of word lexicality and frequency, but not for word regularity. These results show that FPVS response amplitude distinguishes normal from pathological population. Since explicit reading is prohibited by the fast rate, results suggest differences of automatic and implicit word processing in dyslexics. The lack of group difference for regular/irregular words is interpreted post-hoc as reflecting the life-long drill of dyslexics to irregular words. [less ▲]