Responders and non-responders in cognitive rehabilitation (WFNR)

Le Grand Auditorium

jeudi 01 décembre 2022 de 17:00 à 18:30

Président(e): Stéphanie Clarke (Lausanne) Modérateur(s)/Modératrice(s): Isabelle Bonan (Rennes) - Bertrand Glize (Bordeaux)
15:00

 Responders and non-responders in cognitive rehabilitation

Stephanie Clarke (Lausanne, Suisse)

Over the last two decades, new therapeutic interventions were expected to improve significantly outcomes in cognitive rehabilitation. It was therefore disappointing, when large-scale clinical trials reported lack of effectiveness. We have argued that the profiles of responders and non-responders to a specific therapeutic interventions need to be defined on the basis of the underlying neural mechanisms (Clarke et al. 2015 Stroke). I shall illustrate this point with the example of left unilateral neglect.
 
The seminal study of Rossetti and his colleagues (Rossetti et al. 1998 Nature) opened a new chapter in cognitive rehabilitation by demonstrating that a brief exposure to right-deviating prisms (R-PA) alleviates signs of left unilateral neglect. Psychophysical, anatomical and activation studies brought new understanding of the attentional system, its breakdown in neglect and the impact of R-PA (reviewed e. g. in Clarke & Crottaz-Herbette 2016 Neuropsychologia; Clarke et al. 2022 Frontiers in Psychology).
 
Over the last two decades, new therapeutic interventions were expected to improve significantly outcomes in cognitive rehabilitation. It was therefore disappointing, when large-scale clinical trials reported lack of effectiveness. We have argued that the profiles of responders and non-responders to a specific therapeutic interventions need to be defined on the basis of the underlying neural mechanisms (Clarke et al. 2015 Stroke). I shall illustrate this point with the example of left unilateral neglect.
 
The seminal study of Rossetti and his colleagues (Rossetti et al. 1998 Nature) opened a new chapter in cognitive rehabilitation by demonstrating that a brief exposure to right-deviating prisms (R-PA) alleviates signs of left unilateral neglect. Psychophysical, anatomical and activation studies brought new understanding of the attentional system, its breakdown in neglect and the impact of R-PA (reviewed e. g. in Clarke & Crottaz-Herbette 2016 Neuropsychologia; Clarke et al. 2022 Frontiers in Psychology).
 
Neural mechanisms underlying the effect of R-PA involve the steps of visuo-motor recalibration and realignment, with ensuing cognitive effects (reviewed in Panico et al. 2020 Cortex). Major reorganisation takes place at the level of the attentional system, including i) switching the dominance of the ventral attentional system from the right to the left hemisphere (Crottaz-Herbette et al. 2014 Journal of Neuroscience; Crottaz-Herbette et al. 2017 Neuropsychologia; Tissières et al. 2018 Brain Structure and Function); and ii) bilateral increase in responsiveness of the dorsal attentional system (Saj et al. 2013 Cortex). These studies led to the prediction that the beneficial effect on neglect symptoms depends on the integrity of the posterior callosal pathway and the dorsal attentional system (Clarke & Crottaz-Herbette 2016). This prediction has been validated in later studies (Tissières et al. 2017 Neural Plasticity; Goedert et al. 2020 Neuropsychological Rehabilitation; Guttierrez-Herrera et al. 2020 Neuropsychological Rehabilitation; Saj et al. 2019 Cortex).
 
Thus, understanding the mechanisms underlying the effect of R-PA led to the identification of responder vs. non-responder profiles. It highlights the need for new large-scale randomized controlled trials, which take into account the refined indications.


17:30
 
 Determinants of langage after stroke

Thomas Hope (Londres, Gb)

Language impairments (aphasia) are a common consequence of stroke. During the last decade, many new treatments have been proposed for persistent post-stroke aphasia, but often, these treatments appear to work much better for some patients than others. Using the same methods across four different treatment datasets, we show that this inter-individual variance is at least somewhat systematic, and even predictable given patient data acquired before those treatments commenced.
Our approach distinguishes demographic data, pre-treatment behavioural data, lesion location data (extracted algorithmically from structural MRI), and treatment dose data in the 3/4 datasets where this varied significantly from one patient to another. We build Partial Least Squares (PLS) regression models using each data type in isolation, and all combinations of data types (but without further feature selection), and use them to predict each dataset’s treatment responses at better than chance levels.
I end the presentation by describing ongoing work with much larger samples, which aims to optimize these models’ predictive power. 


1810

Stimulation magnétique transcrânienne chez un patient gaucher aphasique suite à un AVC droit : modèle SCED de l'évolution clinique et modifications électrophysiologiques induites

Sophie ARHEIX PARRAS (Bordeaux, France) , Mathilde Du Puy De Goyne (Bordeaux, France) , Grégoire Python (Genève, Suisse) et GLIZE Bertrand (Bordeaux, France)

 

18:20

Résultats d’une étude en multiples cas uniques permettant d’évaluer l’efficacité d’un programme de remédiation cognitive simulant un environnement réel couplée à des stimulations électriques transcrâniennes

Claire LEBELY (Toulouse cedex, France) , Evelyne LEPRON (toulouse, France) , Alizée LELIEVRE (Toulouse cedex, France) , Sebastien Scannella (toulouse, France) et Xavier De Boissezon (Toulouse cedex, France)