Portrait of Danilo Bzdok

Danilo Bzdok

Core Academic Member
bzdokdan@mila.quebec
Canada CIFAR AI Chair
Associate Professor, McGill University, Department of Biomedical Engineering
Research Topics
Computational Biology
Deep Learning
Large Language Models (LLM)
Natural Language Processing

Biography

Danilo Bzdok is a computer scientist and medical doctor by training with a unique dual background in systems neuroscience and machine learning algorithms. After training at RWTH Aachen University (Germany), Université de Lausanne (Switzerland) and Harvard Medical School, Bzdok completed two doctoral degrees, one in neuroscience at Forschungszentrum Jülich in Germany, and another in computer science (machine learning statistics) at INRIA–Saclay and the Neurospin brain imaging centre in Paris.

Danilo is currently an associate professor at McGill University’s Faculty of Medicine and a Canada CIFAR AI Chair at Mila – Quebec Artificial Intelligence Institute. His interdisciplinary research centres around narrowing knowledge gaps in the brain basis of human-defining types of thinking in order to uncover key computational design principles underlying human intelligence.

Current Students

Karan Bali Bali
PhD - McGill University
Gregory Bell
PhD - McGill University
Yanis Bencheikh
Master's Research - HEC Montréal
Co-supervisor :
Tegan Maharaj
Website
Github
Anwesha Bhattacharya
PhD - McGill University
Titouan Brunel
Collaborating researcher - CentraleSupélec
Pedro Carneiro Carneiro
PhD - McGill University
Arthur Communal
Collaborating researcher - École Polytechnique Montréal
Liam Hodgson
PhD - McGill University
Ryan McPhedrain McPhedrain
Postdoctorate - McGill University
David Payette
Master's Research - McGill University
Sepehr Radmannia
Independent visiting researcher - McGill University
Karin Saltoun
PhD - McGill University
Chloé Savignac
PhD - McGill University
Github
Google Scholar
Jack Stanley
PhD - McGill University
Website
Github
Google Scholar
Praneet Suresh
PhD - McGill University
Google Scholar
Yutong Zheng
PhD - McGill University
Le Zhou
PhD - McGill University

Publications

<i>APOE</i> ɛ2 vs <i>APOE</i> ɛ4 dosage shows sex-specific links to hippocampus-default network subregion co-variation
Chloé Savignac
Sylvia Villeneuve
AmanPreet Badhwar
Karin Saltoun
Kimia Shafighi
Chris Zajner
Vaibhav Sharma
Sarah A Gagliano Taliun
Sali Farhan
Judes Poirier
Danilo Bzdok
Alzheimer’s disease and related dementias (ADRD) are marked by intracellular tau aggregates in the medial-temporal lobe (MTL) and extracel… (see more)lular amyloid aggregates in the default network (DN). Here, we sought to clarify ADRD-related co-dependencies between the MTL’s most vulnerable structure, the hippocampus (HC), and the highly associative DN at a subregion resolution. We confronted the effects of APOE ɛ2 and ɛ4, rarely investigated together, with their impact on HC-DN co-variation regimes at the population level. In a two-pronged decomposition of structural brain scans from ∼40,000 UK Biobank participants, we located co-deviating structural patterns in HC and DN subregions as a function of ADRD family risk. Across the disclosed HC-DN signatures, recurrent deviations in the CA1, CA2/3, molecular layer, fornix’s fimbria, and their cortical partners related to ADRD risk. Phenome-wide profiling of HC-DN co- variation expressions from these population signatures revealed male-specific associations with air-pollution, and female-specific associations with cardiovascular traits. We highlighted three main factors associated with brain-APOE associations across the different gene variants: happiness, and satisfaction with friendships, and with family. We further showed that APOE ɛ2/2 interacts preferentially with HC-DN co-variation patterns in estimating social lifestyle in males and physical activity in females. Our findings reinvigorate the often-neglected interplay between APOE ɛ2 dosage and sex, which we have linked to fine-grained structural divergences indicative of ADRD susceptibility.
2022-03-14
bioRxiv (preprint)
doi.org
Cross-ethnicity/race generalization failure of behavioral prediction from resting-state functional connectivity
Jingwei Li
Danilo Bzdok
Jianzhong Chen
Angela Tam
Leon Qi Rong Ooi
Leon Qi Rong Ooi
Avram J. Holmes
Tian Ge
Kaustubh R. Patil
Mbemba Jabbi
Simon B. Eickhoff
B. T. Thomas Yeo
Sarah Genon
Algorithmic biases that favor majority populations pose a key challenge to the application of machine learning for precision medicine. Here,… (see more) we assessed such bias in prediction models of behavioral phenotypes from brain functional magnetic resonance imaging. We examined the prediction bias using two independent datasets (preadolescent versus adult) of mixed ethnic/racial composition. When predictive models were trained on data dominated by white Americans (WA), out-of-sample prediction errors were generally higher for African Americans (AA) than for WA. This bias toward WA corresponds to more WA-like brain-behavior association patterns learned by the models. When models were trained on AA only, compared to training only on WA or an equal number of AA and WA participants, AA prediction accuracy improved but stayed below that for WA. Overall, the results point to the need for caution and further research regarding the application of current brain-behavior prediction models in minority populations.
2022-02-28
Science Advances (published)
doi.org
More Than Meets the Eye: Art Engages the Social Brain
Janneke E. P. van Leeuwen
Jeroen Boomgaard
Danilo Bzdok
Sebastian J. Crutch
Jason D. Warren
2022-02-24
Frontiers in Neuroscience (published)
doi.org
Sex-specific lesion pattern of functional outcomes after stroke
Anna K. Bonkhoff
Martin Bretzner
Sungmin Hong
Markus D. Schirmer
Alexander Cohen
Robert W. Regenhardt
Kathleen L. Donahue
Marco J. Nardin
Adrian V. Dalca
Anne-Katrin Giese
Mark R. Etherton
Brandon L. Hancock
Steven J. T. Mocking
Elissa C. McIntosh
John Attia
Oscar R. Benavente
Stephen Bevan
John W. Cole
Amanda Donatti
Christoph J. Griessenauer … (see 39 more)
Laura Heitsch
Lukas Holmegaard
Katarina Jood
Jordi Jimenez-Conde
Steven J. Kittner
Robin Lemmens
Christopher R. Levi
Caitrin W. McDonough
James F. Meschia
Chia-Ling Phuah
Arndt Rolfs
Stefan Ropele
Jonathan Rosand
Jaume Roquer
Tatjana Rundek
Ralph L. Sacco
Reinhold Schmidt
Pankaj Sharma
Agnieszka Slowik
Martin Söderholm
Alessandro Sousa
Tara M. Stanne
Daniel Strbian
Turgut Tatlisumak
Vincent Thijs
Achala Vagal
Johan Wasselius
Daniel Woo
Ramin Zand
Patrick F. McArdle
Bradford B. Worrall
Christina Jern
Arne G. Lindgren
Jane Maguire
Michael D. Fox
Danilo Bzdok
Ona Wu
Natalia S. Rost
Anna K. Martin Sungmin Markus D. Alexander Robert W. Kathleen L. Marco J. Adrian V. Anne-Katrin Mark R. Brandon L. Steven J. T. Elissa C. John Oscar R. Stephen John W. Amanda Christoph J. Laura Lukas Katarina Jordi Steven J. Robin Christopher R. Caitrin W. James F. Chia-Ling Arndt Stefan Jonathan Jaume Tatjana Ralph L. Reinhold Pankaj Agnieszka Martin Alessandro Tara M. Daniel Turgut Vincent Achala Johan Daniel Ramin Patrick F. Bradford B. Christina Arne G. Jane Michael D. Danilo Ona Natalia S. Bonkhoff
Stroke represents a considerable burden of disease for both men and women. However, a growing body of literature suggests clinically relevan… (see more)t sex differences in the underlying causes, presentations and outcomes of acute ischaemic stroke. In a recent study, we reported sex divergences in lesion topographies: specific to women, acute stroke severity was linked to lesions in the left-hemispheric posterior circulation. We here determined whether these sex-specific brain manifestations also affect long-term outcomes. We relied on 822 acute ischaemic patients [age: 64.7 (15.0) years, 39% women] originating from the multi-centre MRI-GENIE study to model unfavourable outcomes (modified Rankin Scale >2) based on acute neuroimaging data in a Bayesian hierarchical framework. Lesions encompassing bilateral subcortical nuclei and left-lateralized regions in proximity to the insula explained outcomes across men and women (area under the curve = 0.81). A pattern of left-hemispheric posterior circulation brain regions, combining left hippocampus, precuneus, fusiform and lingual gyrus, occipital pole and latero-occipital cortex, showed a substantially higher relevance in explaining functional outcomes in women compared to men [mean difference of Bayesian posterior distributions (men – women) = −0.295 (90% highest posterior density interval = −0.556 to −0.068)]. Once validated in prospective studies, our findings may motivate a sex-specific approach to clinical stroke management and hold the promise of enhancing outcomes on a population level.
2022-01-30
Brain Communications (published)
doi.org
Lacking social support is associated with structural divergences in hippocampus-default network co-variation patterns
Chris Zajner
R. Nathan Spreng
Danilo Bzdok
Elaborate social interaction is a pivotal asset of the human species. The complexity of people’s social lives may constitute the dominatin… (see more)g factor in the vibrancy of many individuals’ environment. The neural substrates linked to social cognition thus appear especially susceptible when people endure periods of social isolation: here, we zoom in on the systematic inter-relationships between two such neural substrates, the allocortical hippocampus (HC) and the neocortical default network (DN). Previous human social neuroscience studies have focused on the DN, while HC subfields have been studied in most detail in rodents and monkeys. To bring into contact these two separate research streams, we directly quantified how DN subregions are coherently co-expressed with specific HC subfields in the context of social isolation. A two-pronged decomposition of structural brain scans from ∼40 000 UK Biobank participants linked lack of social support to mostly lateral subregions in the DN patterns. This lateral DN association co-occurred with HC patterns that implicated especially subiculum, presubiculum, CA2, CA3 and dentate gyrus. Overall, the subregion divergences within spatially overlapping signatures of HC–DN co-variation followed a clear segregation into the left and right brain hemispheres. Separable regimes of structural HC–DN co-variation also showed distinct associations with the genetic predisposition for lacking social support at the population level.
2022-01-24
Social Cognitive and Affective Neuroscience (published)
doi.org
Orientation and Context Entangled Network for Retinal Vessel Segmentation
Xinxu Wei
Kaifu Yang
Danilo Bzdok
Yongjie Li
Most of the existing deep learning based methods for vessel segmentation neglect two important aspects of retinal vessels, one is the orient… (see more)ation information of vessels, and the other is the contextual information of the whole fundus region. In this paper, we propose a robust Orientation and Context Entangled Network (denoted as OCE-Net), which has the capability of extracting complex orientation and context information of the blood vessels. To achieve complex orientation aware, a Dynamic Complex Orientation Aware Convolution (DCOA Conv) is proposed to extract complex vessels with multiple orientations for improving the vessel continuity. To simultaneously capture the global context information and emphasize the important local information, a Global and Local Fusion Module (GLFM) is developed to simultaneously model the long-range dependency of vessels and focus sufficient attention on local thin vessels. A novel Orientation and Context Entangled Non-local (OCE-NL) module is proposed to entangle the orientation and context information together. In addition, an Unbalanced Attention Refining Module (UARM) is proposed to deal with the unbalanced pixel numbers of background, thick and thin vessels. Extensive experiments were performed on several commonly used datasets (DRIVE, STARE and CHASEDB1) and some more challenging datasets (AV-WIDE, UoA-DR, RFMiD and UK Biobank). The ablation study shows that the proposed method achieves promising performance on maintaining the continuity of thin vessels and the comparative experiments demonstrate that our OCE-Net can achieve state-of-the-art performance on retinal vessel segmentation.
2021-12-31
SSRN Electronic Journal (unknown)
doi.org
arxiv.org
Representational ethical model calibration
Robert Carruthers
Isabel Straw
James K. Ruffle
Daniel Herron
Amy Nelson
Danilo Bzdok
Delmiro Fernandez-Reyes
Geraint Rees
Parashkev Nachev
2021-12-31
npj Digit. Medicine (published)
doi.org
arxiv.org
There is no fundamental trade-off between prediction accuracy and feature importance reliability
Jianzhong Chen
L.Q.R. Ooi
Jingwei Li
L. Christopher
Asplund
Simon B. Eickhoff
Danilo Bzdok
Avram J. Holmes
Blake T. Thomas
Yeo
There is significant interest in using neuroimaging data to predict behavior. The predictive models are often interpreted by the computation… (see more) of feature importance, which quantifies the predictive relevance of an imaging feature. Tian and Zalesky (2021) suggest that feature importance estimates exhibit low test-retest reliability, pointing to a potential trade-off between prediction accuracy and feature importance reliability. This trade-off is counter-intuitive because both prediction accuracy and test-retest reliability reflect the reliability of brain-behavior relationships across independent samples. Here, we revisit the relationship between prediction accuracy and feature importance reliability in a large well-powered dataset across a wide range of behavioral measures. We demonstrate that, with a sufficient sample size, feature importance (operationalized as Haufe-transformed weights) can achieve fair to excellent test-retest reliability. More specifically, with a sample size of about 2600 participants, Haufe-transformed weights achieve average intra-class correlation coefficients of 0.75, 0.57 and 0.53 for cognitive, personality and mental health measures respectively. Haufe-transformed weights are much more reliable than original regression weights and univariate FC-behavior correlations. Intriguingly, feature importance reliability is strongly positively correlated with prediction accuracy across phenotypes. Within a particular behavioral domain, there was no clear relationship between prediction performance and feature importance reliability across regression algorithms. Finally, we show mathematically that feature importance reliability is necessary, but not sufficient, for low feature importance error. In the case of linear models, lower feature importance error leads to lower prediction error (up to a scaling by the feature covariance matrix). Overall, we find no fundamental trade-off between feature importance reliability and prediction accuracy.
2021-12-31
(published)
www.semanticscholar.org
Title: Functional architecture of the aging brain
Roni Setton
Laetitia Mwilambwe-Tshilobo
Manesh Girn
Amber W. Lockrow
Giulia Baracchini
Alexander J. Lowe
Benjamin N. Cassidy
Jian Li
Wen-Ming Luh
Danilo Bzdok
Richard M. Leahy
Tian Ge
Daniel S. Margulies
Bratislav Misic
Boris C Bernhardt
W. Dale Stevens
Felipe De Brigard
Prantik Kundu
Richard S. Gary
Gary R. Turner … (see 1 more)
R. Nathan Spreng
The intrinsic functional connectome can reveal how a lifetime of learning and lived experience is represented in the functional architecture… (see more) of the aging brain. We investigated whether network dedifferentiation, a hallmark of brain aging, reflects a global shift in network dynamics, or comprises network-specific changes that reflect the changing landscape of aging cognition. We implemented a novel multi-faceted strategy involving multi-echo fMRI acquisition and de-noising, individualized cortical parcellation, and multivariate (gradient and edge-level) functional connectivity methods. Twenty minutes of resting-state fMRI data and cognitive assessments were collected in younger (n=181) and older (n=120) adults. Dimensionality in the BOLD signal was lower for older adults, consistent with global network dedifferentiation. Functional connectivity gradients were largely age-invariant. In contrast, edge-level connectivity showed widespread changes with age, revealing discrete, network-specific dedifferentiation patterns. Visual and somatosensory regions were more integrated within the functional connectome; default and frontoparietal regions showed greater coupling; and the dorsal attention network was less differentiated from transmodal regions. Associations with cognition suggest that the formation and preservation of integrated, large-scale brain networks supports complex cognitive abilities. However, into older adulthood, the connectome is dominated by large-scale network disintegration, global dedifferentiation and network-specific dedifferentiation associated with age-related cognitive change.
2021-12-31
(published)
www.semanticscholar.org
Recovery after stroke: the severely impaired are a distinct group
Anna K. Bonkhoff
Thomas Hope
Danilo Bzdok
Adrian G. Guggisberg
Rachel L. Hawe
Sean P. Dukelow
François Chollet
David J. Lin
Christian Grefkes
Howard Bowman
Our work highlights the benefit of simultaneously modelling recovery of severely-to-non-severely impaired patients and demonstrates both sha… (see more)red and distinct recovery patterns. Our findings provide evidence that the severe/non-severe subdivision in recovery modelling is not an artefact of previous confounds. The presented out-of-sample prediction performance may serve as benchmark to evaluate promising biomarkers of stroke recovery.
2021-12-21
Journal of Neurology Neurosurgery & Psychiatry (published)
doi.org
Adapting to the COVID‐19 pandemic in cohort studies: Validation of online assessments of cognition and neuropsychiatric symptoms in an aging population
Firoza Z Lussier
Stijn Servaes
Min Su Kang
Gleb Bezgin
Mira Chamoun
Jenna Stevenson
Nesrine Rahmouni
Alyssa Stevenson
Tharick A. Pascoal
Suzanne King
Danilo Bzdok
Serge Gauthier
Pedro Rosa‐Neto
The occurrence of the COVID‐19 pandemic has had a significant impact on cohort studies, particularly those whose subjects are at higher ri… (see more)sk of developing complications from the virus. As such, assessment methods must be adapted to minimize COVID‐19 exposure risk. The TRIAD (Translational Biomarkers of Aging and Dementia) cohort assessed N=292 individuals during initial COVID‐19 lockdown measures by telephone interview to rate cognition, neuropsychiatric symptoms, and impact of the pandemic. To increase speed and efficiency of data collection, we aim to follow these individuals by means of online survey. Here, we present a validation of our online assessment tools by comparing data obtained through both methods (phone interview and online survey) in the same subjects.
2021-11-30
Alzheimer's & Dementia (published)
doi.org
Cognitive health mediates the effect of hippocampal volume on COVID‐19‒related knowledge or anxiety change during the COVID‐19 pandemic
Min Su Kang
Julie Ottoy
Stijn Servaes
Firoza Z Lussier
Gleb Bezgin
Mira Chamoun
Jenna Stevenson
Danilo Bzdok
Suzanne King
Serge Gauthier
Pedro Rosa‐Neto
Our finding highlights the poorer knowledge of COVID19 and related risks in individuals with cognitive/memory impairments; the CDRSOB, indic… (see more)ative of cognitive health, significantly mediated the effect of hippocampal volume on the rate of change in anxiety or knowledge on COVID19 in our cohort. This study urges for a more effective strategy and policy about informing and educating the individual with cognitive/memory impairment on COVID19 and related risks.
2021-11-30
Alzheimer's & Dementia (published)
doi.org