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1.
Dev Neuropsychol ; 38(8): 567-94, 2013.
Article in English | MEDLINE | ID: mdl-24219696

ABSTRACT

Sensitivity to print is characterized by a left occipito-temporal negativity to words in the event-related potential N1. This sensitivity is modulated by reading skills and may thus represent a neural marker of reading competence. Here we studied the development of the N1 in regular and poor readers from preschool age to school age to test whether the amplitude of the N1 predicts children's reading outcomes. Our results suggest a predictive value of the print-sensitive negativity over the right hemisphere. Whether this N1 may serve as a biomarker to improve prognosis in preliterate children should be clarified in future studies.


Subject(s)
Evoked Potentials/physiology , Mental Processes/physiology , Occipital Lobe/physiology , Reading , Temporal Lobe/physiology , Brain Mapping/methods , Case-Control Studies , Child , Child Development , Electroencephalography , Female , Humans , Longitudinal Studies , Male , Neuroimaging , Pattern Recognition, Visual/physiology , Predictive Value of Tests , Time Factors
2.
Neuroimage ; 82: 605-15, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-23727320

ABSTRACT

Children who are poor readers usually experience troublesome school careers and consequently often suffer from secondary emotional and behavioural problems. Early identification and prediction of later reading problems thus are critical in order to start targeted interventions for those children with an elevated risk for emerging reading problems. In this study, behavioural precursors of reading were assessed in nineteen (aged 6.4 ± 0.3 years) non-reading kindergarteners before training letter-speech sound associations with a computerized game (Graphogame) for eight weeks. The training aimed to introduce the basic principles of letter-speech sound correspondences and to initialize the sensitization of specific brain areas to print. Event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) data were recorded during an explicit word/symbol processing task after the training. Reading skills were assessed two years later in second grade. The focus of this study was on clarifying whether electrophysiological and fMRI data of kindergarten children significantly improve prediction of future reading skills in 2nd grade over behavioural data alone. Based on evidence from previous studies demonstrating the importance of initial print sensitivity in the left occipito-temporal visual word form system (VWFS) for learning to read, the first pronounced difference in processing words compared to symbols in the ERP, an occipito-temporal negativity (N1: 188-281 ms) along with the corresponding functional activation in the left occipito-temporal VWFS were defined as potential predictors. ERP and fMRI data in kindergarteners significantly improved the prediction of reading skills in 2nd grade over behavioural data alone. Together with the behavioural measures they explained up to 88% of the variance. An additional discriminant analysis revealed a remarkably high accuracy in classifying normal (n=11) and poor readers (n=6). Due to the key limitation of the study, i.e. the small group sizes, the results of our prediction analyses should be interpreted with caution and regarded as preliminary despite cross-validation. Nevertheless our results indicate the potential of combining neuroimaging and behavioural measures to improve prediction at an early stage, when literacy skills are acquired and interventions are most beneficial.


Subject(s)
Brain Mapping , Brain/physiology , Reading , Child , Evoked Potentials/physiology , Female , Humans , Magnetic Resonance Imaging , Male , Pattern Recognition, Visual/physiology
3.
Neuroimage ; 2011 Jul 23.
Article in English | MEDLINE | ID: mdl-21802519

ABSTRACT

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

4.
Neuroimage ; 53(2): 682-93, 2010 Nov 01.
Article in English | MEDLINE | ID: mdl-20600985

ABSTRACT

Phonological awareness refers to the ability to perceive and manipulate the sound structure of language and is especially important when children learn to read. Poor phonological awareness is considered the major cause for the emergence of reading difficulties. In this functional magnetic resonance imaging (fMRI) study, we examined the brain correlates of phonological processing in young beginning readers (aged 8.3+/-0.4 y, 2nd grade) with poor (<25th percentile) or normal, age-appropriate reading skills (>40th percentile) using a covert reading and mental letter substitution task. Letter substitution in words and nonwords induced pronounced activity in a left frontal language network related to phonological processing, with maxima in the left inferior frontal gyrus and in the insula. The activation within this frontal network increased with better reading skills and differentiated between normal and poor reading young children. Lateralization indices of overall frontal activity for normal and poor readers pointed to stronger left hemispheric involvement in normal readers as compared to the more bilateral activation pattern in poor readers. To summarize, young children with age-appropriate reading skills display a left hemispheric dominance characteristic for language processing already by grade two. The more bilateral activation pattern in poor readers points to an increased effort and the emergence of compensatory strategies for reading and phonological processing just 1.5 years after the start of formal reading instruction.


Subject(s)
Dyslexia/physiopathology , Frontal Lobe/physiopathology , Brain/physiology , Brain Mapping , Child , Electroencephalography , Female , Functional Laterality/physiology , Handwriting , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Prefrontal Cortex/physiology , Psychomotor Performance/physiology , Reading
5.
Proc Natl Acad Sci U S A ; 107(17): 7939-44, 2010 Apr 27.
Article in English | MEDLINE | ID: mdl-20395549

ABSTRACT

The acquisition of reading skills is a major landmark process in a human's cognitive development. On the neural level, a new functional network develops during this time, as children typically learn to associate the well-known sounds of their spoken language with unfamiliar characters in alphabetic languages and finally access the meaning of written words, allowing for later reading. A critical component of the mature reading network located in the left occipito-temporal cortex, termed the "visual word-form system" (VWFS), exhibits print-sensitive activation in readers. When and how the sensitivity of the VWFS to print comes about remains an open question. In this study, we demonstrate the initiation of occipito-temporal cortex sensitivity to print using functional MRI (fMRI) (n = 16) and event-related potentials (ERP) (n = 32) in a controlled, longitudinal training study. Print sensitivity of fast (<250 ms) processes in posterior occipito-temporal brain regions accompanied basic associative learning of letter-speech sound correspondences in young (mean age 6.4 +/- 0.08 y) nonreading kindergarten children, as shown by concordant ERP and fMRI results. The occipito-temporal print sensitivity thus is established during the earliest phase of reading acquisition in childhood, suggesting that a crucial part of the later reading network first adopts a role in mapping print and sound.


Subject(s)
Language , Occipital Lobe/physiology , Pattern Recognition, Visual/physiology , Reading , Temporal Lobe/physiology , Analysis of Variance , Brain Mapping , Child , Child, Preschool , Evoked Potentials , Humans , Magnetic Resonance Imaging
6.
J Vestib Res ; 17(5-6): 279-87, 2007.
Article in English | MEDLINE | ID: mdl-18626138

ABSTRACT

The aim of this experiment was to investigate the influence of gravity on the cognitive ability to mentally transform images of bodies or body parts. A total of eight participants were tested in two separate parabolic flight missions. In the main experiment, participants had to make a discrimination judgement (left or right) about pictures of a human figure with one arm outstretched, and pictures of a body part (hand). The stimuli appeared in varying views and orientations. Response times and error rates were measured. In microgravity, the participants showed increased response times overall as well as increased error rates when compared to 1 g for both types of stimuli. Thus, a task that requires the mental transformation of one's own body or body parts becomes more difficult during microgravity. This is in contrast to previous studies showing no effect of microgravity on the mental rotation of abstract 3D objects and to our follow-up case study in which participants applied an object-based mental rotation strategy. Moreover, the analysis of response times suggests that in microgravity body-part stimuli are affected more strongly than body figures.


Subject(s)
Body Image , Weightlessness , Adult , Female , Humans , Male , Middle Aged , Rotation , Space Flight , Task Performance and Analysis
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