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Scanpath variation in individuals with 22q11.2 deletion syndrome during the Benton Visual Retention Test . Marie-Christine Ottet, Bronwyn Glaser, Manolo Fuentes, Catherine Pasca, M él anie Chabloz, Martin Debban é , Stephan Eliez. How do we look at things ?. Why is this pertinent to VCFS ?.
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Scanpath variation in individuals with 22q11.2 deletion syndrome during the Benton Visual Retention Test Marie-Christine Ottet, Bronwyn Glaser, Manolo Fuentes, Catherine Pasca, Mélanie Chabloz, Martin Debbané, Stephan Eliez
Why is this pertinent to VCFS ? Previous findings: • Deficits in attentional skills (Simon et al., 2002; Bish et al., 2005) • Efficient scanpath needs attention • Deficits of visuo-spatial memory (Bearden et al., 2001) • Alteration of parietal lobe (Simon et al., 2005) • Memory relies on visual exploration • Parents report an incomplete visual exploration
Population • 78 participants • 41 VCFS and 38 Controls • Range of age : 8 to 26 years • 2 types of evaluation : • Cognitive: with an Eyetracker • Cerebral: with MRI scans
Benton Visual Retention (Test BVRT)Computer version • BVRT multiple choice • 10 cards with geometric figures
How to measure and analyze the scanpath • Eyetracker Tobii 1750 • Measurements of the eyetracker • Total time and spread of exploration • Number, duration and coordinates of fixation points • Analyze regions of interest (AOI) • 3 groups of figures • Main simple figure • Main complex figure • Peripheral figure
Global Results • Less fixations • More spread • Same areas oberved Controls VCFS Controls VCFS
Results of AOI In red : lower number of fixations made by VCFS 10.78>8.67 8.45>6.83 10.24>8.63 2.68>1.44 Image 3 Image 1 Image 2 5.50>4.59 2.11>1.15 2.29>1.54 Image 4 Image 5 Image 6 3.58>2.56 2.34>1,51 1.45>0.98 1.39>0.83 1.76>1.12 5.87>4.22 Image 7 • Image 8 Image 9 4.82>3.71 1.42>0.59 Image 10
Results: Analysis of AOI • Less fixations on : • 7 of 8 peripheral figures • 5 of 7 main simple figures • 2 influences: • Spatial deficits Lateral « negletion » of the image • Less fixations on peripheral figures • Alterations of the parietal lobe • Attentional deficits Deficit in attentional disengagement • Less fixations on main figures simples • Alterations of the frontal lobe Image 1 Image 2 Image 3 Image 5 Image 6 Image 4 Image 7 • Image 8 Image 9 Image 10
Anatomical cerebral measurments • Method : FreeSurfer (http://surfer.nmr.mgh.harvard.edu/) Measure of the volume of gray matter of the cortex • parcels of frontal lobe • parcels of parietal lobe Automatic subdivision of the cortex: Desikan, R.S., (2006)
Analysis of parcel volumes related to the scanpath Left hemisphere • Correlations controled for age and gender between : • Gray matter volume • AOIs • Caudal middle frontal • Precentral • Postcentral • Superior frontal • Anterior cingulate • Parahippocampal Right hemisphere • Caudal middle frontal
In summary • Same areas observed between groups but less precise scanpath in VCFS (number, duration and spread) • Deficits attentional and spatial on global scanpath • Possible alteration of the motor planification
How do our results guide interventions ? • Importance in treatment of attentional deficit: • Cognitive remediation • Medical treatments • Strategies • Always start with the sides of images • Salient stimulus on important items (e.g. key word in red for homework)
Thank you… … for your attention
Acknowledgment Thanks to the associations Generation22 Connect22 Relais22 Financial Support SNF CIBM Eagle FHMS NARSAD Von Meissner Thanks to collegues Stephan Eliez Martin Debbané Bronwyn Glaser AnnaLaura Lagioia Marie Schaer Maude Schneider Catherine Pasca Mélanie Chabloz Bertrand Auckenthaler Michal Epstein Catherine Audrin Manolo Fuentes Ryan Murray Thanks to all the families