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Gillebert, C. R.

Publications and source records attributed to Gillebert, C. R..

2 recordsLinked to original sources

The ViRA-L (Visual Recognition Assessment-Leuven): Development, Validation, and Age Stratified Normative Characterization of a Multi-Category Visual Recognition Battery

Objective: To develop and validate the Visual Recognition Assessment-Leuven (ViRA-L), a recognition-memory battery assessing ten visual categories within a matched task structure, and provide age-stratified normative data. Method: Healthy Dutch-speaking adults completed a visual recognition task for ten categories. Each category included six targets, 18 Learning trials, and 30 Novel trials requiring recognition across appearance changes. After exclusions, 417 participants remained. We evaluated reliability, score distributions, task effects, demographic associations, and category-specific norms. Results: Battery-level internal consistency was good (Cronbach's = .879; omega total = .901), with lower category-level estimates, broad score dispersion, and minimal floor and ceiling effects. Novel and difficult trials produced lower accuracy and slower responses. Age was the clearest demographic correlate of accuracy; gender and education showed no independent overall associations. Age effects varied by category and were larger in Novel than Learning trials. Model-based differences between ages 50 and 85 were largest for Pseudowords and Hands and smallest for Houses. Conclusions: The ViRA-L supports comparison of recognition-memory profiles under matched procedures. Category-dependent age associations support age-sensitive, category-specific interpretation. The battery provides a foundation for neuropsychological research; further validation is required for clinical diagnostic use.

neuroscience↗

Multi-method brain imaging reveals impaired representations as well as altered connectivity in adults with dyscalculia

Two hypotheses have been proposed about the etiology of neurodevelopmental disorders: representation impairments versus disrupted access to representations. We implemented a multi-method brain imaging approach to directly compare the representation vs. access hypotheses in dyscalculia, a highly prevalent but understudied neurodevelopmental disorder in learning to calculate. We combined several magnetic resonance imaging methods and analyses, including multivariate analyses, functional and structural connectivity, and voxel-based morphometry analysis, in a sample of 24 adults with dyscalculia and 24 carefully matched controls. Results showed a clear deficit in the non-symbolic magnitude representations in parietal, temporal, and frontal regions in dyscalculia. We also observed hyper-connectivity in visual brain regions and increased grey matter volume in the default mode network in adults with dyscalculia. Hence, dyscalculia is related to a combination of diverse neural markers which are altogether distributed across a substantial portion of cerebral cortex, supporting a multifactorial model of this neurodevelopmental disorder.

neuroscience↗