Neurocognitive study of procedural learning and procedural memory in Dyslexia and Developmental Coordination Disorder – DYSTAC-MAP

This project proposes to compare procedural learning and retention in both disorders (Dyslexia and DCD), when they are isolated or associated. A comparison will be made with two control groups, one group comprising typically developped children and the other children with genetic pathology (Neurofibromatosis type 1) in which frequent association of reading and motor disorders is reported. This project seeks also to specify the children difficulties encountered in each procedural task. The response modalities in the six learning tasks are verbal or motor and allow us to test the different combinations. Finally, we want to determine correlations between cognitive markers obtained during the neuropsychological assessment, cerebral markers from brain MRI and behavioral data obtained during the procedural learning tasks.

197 children were included in 5 groups (48 DD Dyslexia, 28 DCD Developmental Coordination Disorder, 35 DD + DCD, 44 NF1 and 42 controls)
First conclusions:
Regarding specific disorders (DD, TDC) isolated or co-morbid (DD + TDC):
• The deficit in phonological processes is linked to reading disorder and characterizes children with DD and the DD + DCD association
• The deficit of visuo-attentional processes does not discriminate the ? NDD Neuro Developmental Disorders groups however, impairment of the visuospatial dimension is more frequent in DCD
• No general deficit in procedural learning in NDDs is found
• However, according the NDDs (DD, DCD or DD + DCD) certain conditions can degrade these learning capacities
• The first results in brain imaging do not support the hypothesis of impairment of the cortico-cerebellar or striatal loops, making it possible to differentiate NDDs
• The association of two disorders (DD + DCD) is not necessarily a systematic marker of poor prognosis
Regarding NF1:
• At the cerebral level, it is the structural indices more than functional (in particular mean diffusivity) which make it possible to better differentiate NF1 subjects from control subjects with implications of the subcortical and hippocampal regions.
• The study of the memory profile of NF1 children finds a predominant impairment in working memory, more precisely the phonological loop, and in episodic memory
• At the level of memory and procedural learning, the learning of motor sequences (cortico-striatal loops) is respected but the motor adaptation is altered (cortico-cerebellar loops)
• These neuropsychological impairments only concern certain subgroups of NF1 children in favor of great heterogeneity at the cognitive and cerebral level
• The lack of correlation between cognitive and cerebral markers could be partly explain by this heterogeneity

The ANR Project made it possible to strengthen the synergy between the Aix-Marseille and Toulouse teams and to initiate new collaborations on the theme of learning and its disorders.
The IMPALA Study aims to access learning and procedural memory in the context of acquired disorders with the evaluation of the impact in children of posterior fossa tumors ‘s treatments on memories and procedural learning - Collaboration INSERM Toulouse & LNC UMR7291 Laboratory of Cognitive Neurosciences - Aix-Marseille

Cross-sectional (HELP REAGING) and longitudinal (VISALECT) studies in the NF1 context aim to better specify the impact of visuo-attentional and oculomotor capacities on reading learning in NF1 children. The final objective being the prevention of reading difficulties frequently observed in this population. Collaboration INSERM Toulouse & Laboratory Speech and Language, Aix-en-Provence - UMR 7309

Finally, the coordinated study by J. Danna (LNC UMR7291 Laboratory of Cognitive Neurosciences - Aix-Marseille) and M. Jover (PsyCLE, EA 3273 Center Psychologie de la Connaissance, du Langage et de l'énergie - Aix-Marseille) aims the creation and validation of a handwriting rehabilitation tool for dysgraphic children on a digital tablet.

Publications until August 1rst, 2020

1- Maziero S, Tallet J, Bellocchi S, Jover M, Chaix Y, Jucla M. Influence of Comorbidity on Working Memory Profile in Dyslexia and Developmental Coordination Disorder. Journal of Clinical and Experimental Neuropsychology (Accepté le 13 juillet 2020). (IF: 1,97)
2- Baudou E, Nemmi F, Biotteau M, Maziero S, Peran P, Chaix Y. Are morphological and structural MRI characteristics related to specific cognitive impairments in Neurofibromatose Type 1 (NF1) children? European Journal of Pediatric Neurology (Accepté le11 juin 2020) (IF: 2.510).
3- Lê M, Blais M, Jucla M, Chauveau N, Maziero S, Biotteau M, Albaret JM, Péran P, Chaix Y, Tallet J. Procedural learning and retention of audio-verbal temporal sequence is altered in children with Developmental Coordination Disorder but cortical thickness matters. Dev Sci. 2020 Jun 23:e13009. doi: 10.1111/desc.13009. (IF: 4.078)
4- Nemmi F, Cignetti F, Assaiante C, Maziero S, Audic F, Peran P, Chaix.Y. Discriminating between neurofibromatosis 1 and typically developing children by means of multimodal MRI and multivariates analyses. Hum Brain Mapp. 2019 Aug 15;40(12): 3508-3521. (F: 4.421)
5- Biotteau M, Danna J, Baudou E, Puyjarinet F, Velay JL, Albaret JM, Chaix Y. Developemental coordination disorder and dysgraphia : signs, symptoms, diagnosis and rehabilitation. Neuropsychiatric Disease and Treatment 2019:15 1873–1885 (IF: 2.157)
6- Cignetti F, Vaugoyeau M, Decker LM, Grosbras MH, Girard N, Chaix Y, Péran P, Assaiante C. Brain network connectivity associated with anticipatory control in children and adult. Cortex. 2018 Sep 1;108:210-221. (IF: 4.275)
7- Biotteau, M., Chaix, Y., Blais, M., Tallet, J., Peran, P., Albaret, J.M. Neural Signature of DCD : A critical review of MRI Neuroimaging studies. Frontiers in Neurology, Published 16 dec 2016. (IF: 3.508)

Specific learning and developmental disorders are one of the major causes of school failure among children with psychological and social implications. Developmental Dyslexia (DYS) and Developmental Coordination Disorder (DCD) are common reasons for child out-patient paediatric consultation. Their frequent association however suggests the existence of a common etiology. The hypothesis of a procedural learning and memory deficit in both disorders, as proposed by Nicolson and Fawcett (2007) assumes the existence of a dysfunction of the neural bases of procedural learning, namely cortico-striatal and cortico-cerebellar loops, distinctly recruited depending on the type of task and learning phase. A still open question is to what extent are these loops defective in DYS and DCD: are they “disorder-specific”, or do they constitute a common grounding? This issue stands for a real theoretical challenge given the contradictory findings reported in the recent literature.
This research project aims at studying procedural learning and memory in children with a specific developmental disorder (DYS or DCD) or with both types of deficits (DYS and DCD). A comparison with a control group, consisting of typically developing children, will able us to dissociate the supposed procedural difficulties (learning and memory) that are specific and/or common to DYS and/or DCD. A second control group will involve children with reading and motor learning disabilities due to a genetic disorder, i.e. Neurofibromatosis type 1 (NF1). Comparing these different groups constitute the first novelty in our approach.
The second aim is to further investigate the deficits according to the procedural task at stake. According to Doyon and Benali (2005), sequence learning recruits the cortico-striatal loop while perceptual-motor adaptations mainly involve the cortico-cerebellar loop. Each type of learning may imply motor or verbal processes (input or response). Therefore, six behavioural tasks will test different combinations of circuit/processes. DYS, DCD and NF1 children should have common or specific learning and retention deficits according to the proposed combination. This stands for another originality of our proposal.
The last objective is to determine cognitive and neural predictive markers of learning and its immediate and long-term retention efficiency. Cognitive markers will be obtained in a comprehensive neuropsychological assessment. MRI data (DTI, resting-state and morphometry) will give us information about the cerebral architecture and connectivity. A complementary goal will be to analyse correlations between cerebral and cognitive measures obtained during neuropsychological assessments as well as experimental tasks. This last part of the project represents quite an original method.
This innovative project brings together researchers from complementary scientific backgrounds (linguistics, sports sciences, developmental psychology, neuroscience) from two research sites (Toulouse and Marseille) whose research interests are close. The different partners have already obtained preliminary data, suggesting the existence of a common aetiology to DYS and DCD and strengthening hypotheses on which this research is based on. The project will provide new theoretical insights into common and distinct deficits observed in children with DYS and DCD and will allow new opportunities for assessing procedural deficits. Finally, being able to precise failure predictors may offer us to propose new evidence-based training programmes targeted on learning deficits in the different population.