Transcript ROME

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
How do we look at things ?
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
Image 1
Image 2
Image 3
Image 4
Image 5
Image 6
Image 7
Image 8
Image 9
Image 10
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
VCFS
Controls
VCFS
Controls
• Less fixations
• More spread
• Same areas
oberved
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 1
Image 3
Image 2
5.50>4.59
2.11>1.15
2.29>1.54
Image 4
Image 5
Image 6
3.58>2.56
1.45>0.98
2.34>1,51
1.39>0.83
5.87>4.22
Image 7
Image 8
Image 9
4.82>3.71
Image 10
1.76>1.12
1.42>0.59
Results: Analysis of AOI
• Less fixations on :


7 of 8 peripheral figures
5 of 7 main simple figures
• 2 influences:
Image 1
Image 2
Image 3
Image 4
Image 5
Image 6
Image 7
Image 8
1. Spatial deficits
Lateral « negletion » of the image
 Less fixations on peripheral figures
 Alterations of the parietal lobe
2. Attentional deficits
Deficit in attentional disengagement
 Less fixations on main figures simples
 Alterations of the frontal lobe
Image 10
Image 9
Anatomical cerebral measurments
• Method : FreeSurfer (http://surfer.nmr.mgh.harvard.edu/)
Measure of the volume of
gray matter of the cortex
Automatic subdivision of the cortex: Desikan, R.S., (2006)
– parcels of frontal lobe
– parcels of parietal lobe
Analysis of parcel volumes related to the
scanpath
• Correlations
controled for age and
gender between :
Left hemisphere
• Gray matter
volume
• AOIs
•Caudal middle frontal
•Superior frontal
•Precentral
•Anterior cingulate
•Postcentral
Right hemisphere
•Caudal middle frontal
•Parahippocampal
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 all
families
Thanks to collegues
Stephan Eliez
Martin Debbané
Bronwyn Glaser
AnnaLaura Lagioia
Marie Schaer
Maude Schneider
Catherine Pasca
Mélanie Chabloz
Bertrand Auckenthaler
Michal Epstein
the
Catherine Audrin
Manolo Fuentes
Ryan Murray