What role does neurofibromatosis type 1 play in learning to read?

We are pleased to announce the recent publication of the latest article produced by Marie Vernet (neuropsychologist and former doctoral student at LPL), Stéphanie Ducrot (CNRS researcher at LPL) and Yves Chaix (Tonic, CHU Toulouse) which includes a systematic review on visual processing deficits in neurofibromatosis type 1 and the impact on learning to read.

It follows the study “The determinants of saccade targeting strategy in neurodevelopmental disorders: The influence of suboptimal reading experience” published in 2023 in the journal Vision Research.

Reference: Marie Vernet, Stéphanie Ducrot, Yves Chaix. A systematic review on visual-processing deficits in Neurofibromatosis type 1: what possible impact on learning to read?. Developmental Neuropsychology, 2024

Editors Website: https://www.tandfonline.com/doi/full/10.1080/87565641.2024.2326151

Full text article: https://hal.science/hal-04504105


Credits: The authors

Learning to read with Neurofibromatosis Type 1

We are pleased to share with you the latest article published in the journal Vision Research by Marie Vernet (ToNIC / LPL / CLLE) and Stéphanie Ducrot (LPL) in collaboration with colleagues from Aix, Montpellier and Toulouse:

Reference: Vernet, M., Bellocchi, S., Danna, J., Massendari, D., Jover, M., Chaix, Y., Ducrot, S. (2023). The determinants of saccade targeting strategy in neurodevelopmental disorders: The influence of suboptimal reading experience. Vision Research, 204, 108162 https://doi.org/10.1016/j.visres.2022.108162

 Abstract: Whether eye-movements deficits are causal in reading disorders (RD) or rather a consequence of linguistic processing difficulty experienced by disabled readers has been extensively debated.Since RD are frequently comorbid with the Neurofibromatosis type1 (NF1), children with NF1 were used as a comparison group for children with dyslexia in this study.Eye movements were recorded while 21 dyslexic, 20 NF1, and 20 typically developing children performed an oculomotor lateralized bisection task. In this experiment, we manipulated the type of stimulus - discrete (words and strings of hashes) versus continuous (solid lines) - and the visual field where the stimulus was displayed (left vs right). The results showed that (1) only proficient readers (TD and NF1 without RD) showed fully developed oculomotor mechanisms for efficient reading, with a clear preferred viewing location located to the left of the word's centre in both visual fields, and fine-tuned saccade targeting guided by the between-character space information and (2) NF1 poor readers mirrored the dyslexic eye movement behaviour, with less accuracy and more variability in saccadic programming, no sensitivity to the discreteness of the stimuli, particularly in the left visual field. We concluded that disruption to oculomotor behaviour reflectsthe fact that many of the processes involved in reading are not yet automatized for children with RD, independently of NF1. This suggests that the differences in saccade targeting strategy between children with and without RD would be secondary consequences of their reduced reading experience.

Reference @HAL (article under embargo, available on request): https://hal-amu.archives-ouvertes.fr/LPL-AIX/hal-03924190v1


Photo: 8-year-old child with NF1. Credits: Authors of the publication.