Publications de Marie Schaer | EPFL Graph Search

Structural control energy of resting-state functional brain states reveals less cost-effective brain dynamics in psychosis vulnerability

Dimitri Nestor Alice Van De Ville, Marie Schaer

How the brain's white-matter anatomy constrains brain activity is an open question that might give insights into the mechanisms that underlie mental disorders such as schizophrenia. Chromosome 22q11.2 deletion syndrome (22q11DS) is a neurodevelopmental dis ...

Wiley2021

Identifying neurodevelopmental anomalies of white matter microstructure associated with high risk for psychosis in 22q11.2DS

Marie Schaer, Maude Schneider, Maria Carmela Padula, Daniela Maria Zöller

Disruptions of white matter microstructure have been widely reported in schizophrenia. However, the emergence of these alterations during preclinical stages remains poorly understood. 22q11.2 Deletion Syndrome (22q11.2DS) represents a unique model to study ...

SPRINGERNATURE2020

Dynamic spatiotemporal patterns of brain connectivity reorganize across development

Patric Hagmann, Marie Schaer, Alessandra Griffa, Emeline Mullier

Late human development is characterized by the maturation of high-level functional processes, which rely on reshaping of white matter connections, as well as synaptic density. However, the relationship between the whole-brain dynamics and the underlying wh ...

MIT PRESS2020

Pituitary dysmaturation affects psychopathology and neurodevelopment in 22q11.2 Deletion Syndrome

Dimitri Nestor Alice Van De Ville, Maria del Carmen Sandi Perez, Marie Schaer, Maude Schneider, Maëlle Chambaz, Daniela Maria Zöller

Background 22q11.2 Deletion Syndrome (22q11DS) confers strongly increased genetic risk for multiple psychiatric disorders. Similarly to the general population, rates of psychiatric comorbidity suggest that common disease mechanisms are shared across dimens ...

2020

Large-Scale Brain Network Dynamics Provide a Measure of Psychosis and Anxiety in 22q11.2 Deletion Syndrome Daniela

Dimitri Nestor Alice Van De Ville, Marie Schaer, Fikret Isik Karahanoglu, Maria Carmela Padula

BACKGROUND: Prodromal positive psychotic symptoms and anxiety are two strong risk factors for schizophrenia in 22q11.2 deletion syndrome (22q11DS). The analysis of large-scale brain network dynamics during rest is promising to investigate aberrant brain fu ...

ELSEVIER2019

Robust Recovery of Temporal Overlap Between Network Activity Using Transient-Informed Spatio-Temporal Regression

Dimitri Nestor Alice Van De Ville, Marie Schaer, Fikret Isik Karahanoglu, Thomas William Arthur Bolton, Daniela Maria Zöller

Functional magnetic resonance imaging is a non-invasive tomographic imaging modality that has provided insights into system-level brain function. New analysis methods are emerging to study the dynamic behavior of brain activity. The innovation-driven co-ac ...

Institute of Electrical and Electronics Engineers2019

Cortical Dysconnectivity Measured by Structural Covariance Is Associated With the Presence of Psychotic Symptoms in 22q11.2 Deletion Syndrome

Dimitri Nestor Alice Van De Ville, Marie Schaer, Maude Schneider, Maria Carmela Padula

BACKGROUND: 22q11.2 deletion syndrome (22q11DS) is the third-largest known genetic risk factor for the development of psychosis. Dysconnectivity has consistently been implicated in the physiopathology of psychosis. Structural covariance of cortical morphol ...

2018

Cortical morphology development in patients with 22q11.2 deletion syndrome at ultra-high risk of psychosis

Marie Schaer, Maude Schneider, Maria Carmela Padula, Daniela Maria Zöller

Background. Patients with 22q11.2 deletion syndrome (22q11DS) present a high risk of developing psychosis. While clinical and cognitive predictors for the conversion towards a full-blown psychotic disorder are well defined and largely used in practice, neu ...

CAMBRIDGE UNIV PRESS2018

Disentangling resting-state BOLD variability and PCC functional connectivity in 22q11.2 deletion syndrome

Dimitri Nestor Alice Van De Ville, Marie Schaer, Maria Carmela Padula, Daniela Maria Zöller

Although often ignored in fMRI studies, moment-to-moment variability of blood oxygenation level dependent (BOLD) signals reveals important information about brain function. Indeed, higher brain signal variability has been associated with better cognitive p ...

Elsevier2017

An affected core drives network integration deficits of the structural connectome in 22q11.2 deletion syndrome

Patric Hagmann, Marie Schaer, Alessandra Griffa, Frantisek Vasa

Chromosome 22q11.2 deletion syndrome (22q11DS) is a genetic disease known to lead to cerebral structural alterations, which we study using the framework of the macroscopic white-matter connectome. We create weighted connectomes of 44 patients with 22q11DS ...

Elsevier Sci Ltd2016

Graph theory reveals dysconnected hubs in 22q11DS and altered nodal efficiency in patients with hallucinations

Jean-Philippe Thiran, Marie Schaer, Leila Cammoun

Schizophrenia is postulated to be the prototypical dysconnection disorder, in which hallucinations are the core symptom. Due to high heterogeneity in methodology across studies and the clinical phenotype, it remains unclear whether the structural brain dys ...

Frontiers Research Foundation2013

Reduced Fronto-Temporal and Limbic Connectivity in the 22q11.2 Deletion Syndrome: Vulnerability Markers for Developing Schizophrenia?

Jean-Philippe Thiran, Marie Schaer, Leila Cammoun

The 22q11.2 deletion syndrome (22q11DS) is a widely recognized genetic model allowing the study of neuroanatomicalvbiomarkers that underlie the risk for developing schizophrenia. Recent advances in magnetic resonance image analysesvenable the examination o ...

Public Library of Science2013

Optical and morphological characterisation of low refractive index materials for coatings on solar collector glazing

Jean-Louis Scartezzini, Andreas Schueler, Estelle De Chambrier, Marie Schaer, Martin Joly, Stefan Mertin, Virginie Hody-Le Caër

Nanostructured coatings based on the elements Si, O, Mg, and F have been deposited as thin films by solegel dip-coating in a particle-free atmosphere. The refractive index of the prepared SiO2 and quaternary MgeFeSieO thin films has been determined from sp ...

Pergamon-Elsevier Science Ltd2013

How to Measure Cortical Folding from MR Images: a Step-by-Step Tutorial to Compute Local Gyrification Index

Jean-Philippe Thiran, Meritxell Bach Cuadra, Marie Schaer

Cortical folding (gyrification) is determined during the first months of life, so that adverse events occurring during this period leave traces that will be identifiable at any age. As recently reviewed by Mangin and colleagues2, several methods exist to q ...

2012

Regional cortical volumes and congenital heart disease: a MRI study in 22q11.2 deletion syndrome

Jean-Philippe Thiran, Meritxell Bach Cuadra, Marie Schaer, Maude Schneider

Children with congenital heart disease (CHD) who survive surgery often present impaired neurodevelopment and qualitative brain anomalies. However, the impact of CHD on total or regional brain volumes only received little attention. We address this question ...

2010

Prefrontal Plasticity and Stress Inoculation-Induced Resilience

Marie Schaer

Coping with mild early life stress tends to make subsequent coping efforts more effective and therefore more likely to be used as a means of arousal regulation and resilience. Here we show that this developmental learning-like process of stress inoculation ...

2009

Hippocampal volume and declarative memory function in combat-related PTSD

Marie Schaer

The proposition that declarative memory deficits are systematically related to smaller hippocampal Volume was tested in a relatively large sample (n = 95) of U.S. military veterans with and without combat-related posttraumatic stress disorder. This correla ...

Cambridge University Press2009

Smaller Global and Regional Cortical Volume in Combat-Related Posttraumatic Stress Disorder

Marie Schaer

Context Two sets of findings predict smaller cerebral cortical gray matter volume in adult posttraumatic stress disorder (PTSD). Measures of intracranial tissue volume and cerebral tissue volume have been observed to be smaller in adolescents with maltreat ...

2009

Congenital heart disease affects local gyrification in 22q11.2 deletion syndrome

Jean-Philippe Thiran, Meritxell Bach Cuadra, Marie Schaer

22q11.2 deletion syndrome (22q11.2DS) is a common genetic condition associated with cognitive and learning impairments. In this study, we applied a threedimensional method for quantifying gyrification at thousands of points over the cortical surface to ima ...

Wiley-Blackwell2009

Brain Surface Segmentation of Magnetic Resonance Images of the Fetus

Jean-Philippe Thiran, Meritxell Bach Cuadra, Dominique Zosso, Nawal Houhou, Marie Schaer, Damien Ferrario

In this work we present a method for the image analysis of Magnetic Resonance Imaging (MRI) of fetuses. Our goal is to segment the brain surface from multiple volumes (axial, coronal and sagittal acquisitions) of a fetus. To this end we propose a two-step ...

2008