Publications

Recurrent Traumatic Brain Injury Surveillance Using Administrative Health Data: A Bayesian Latent Class Analysis

Oliver Lasry

Nandini Dendukuri

Judith Marcoux

David L. Buckeridge

Background: The initial injury burden from incident TBI is significantly amplified by recurrent TBI (rTBI). Unfortunately, research assessin… (see more)g the accuracy to conduct rTBI surveillance is not available. Accurate surveillance information on recurrent injuries is needed to justify the allocation of resources to rTBI prevention and to conduct high quality epidemiological research on interventions that mitigate this injury burden. This study evaluates the accuracy of administrative health data (AHD) surveillance case definitions for rTBI and estimates the 1-year rTBI incidence adjusted for measurement error.Methods: A 25% random sample of AHD for Montreal residents from 2000 to 2014 was used in this study. Four widely used TBI surveillance case definitions, based on the International Classification of Disease and on radiological exams of the head, were applied to ascertain suspected rTBI cases. Bayesian latent class models were used to estimate the accuracy of each case definition and the 1-year rTBI measurement-error-adjusted incidence without relying on a gold standard rTBI definition that does not exist, across children (<18 years), adults (18-64 years), and elderly (> =65 years).Results: The adjusted 1-year rTBI incidence was 4.48 (95% CrI 3.42, 6.20) per 100 person-years across all age groups, as opposed to a crude estimate of 8.03 (95% CrI 7.86, 8.21) per 100 person-years. Patients with higher severity index TBI had a significantly higher incidence of rTBI compared to patients with lower severity index TBI. The case definition that identified patients undergoing a radiological examination of the head in the context of any traumatic injury was the most sensitive across children [0.46 (95% CrI 0.33, 0.61)], adults [0.79 (95% CrI 0.64, 0.94)], and elderly [0.87 (95% CrI 0.78, 0.95)]. The most specific case definition was the discharge abstract database in children [0.99 (95% CrI 0.99, 1.00)], and emergency room visits claims in adults/elderly [0.99 (95% CrI 0.99, 0.99)]. Median time to rTBI was the shortest in adults (75 days) and the longest in children (120 days).Conclusion: Conducting accurate surveillance and valid epidemiological research for rTBI using AHD is feasible when measurement error is accounted for.

2021-05-13

Frontiers in Neurology (published)

doi.org

Burst-dependent synaptic plasticity can coordinate learning in hierarchical circuits

Alexandre Payeur

Jordan Guerguiev

Friedemann Zenke

Blake A. Richards

Richard Naud

Synaptic plasticity is believed to be a key physiological mechanism for learning. It is well-established that it depends on pre and postsyna… (see more)ptic activity. However, models that rely solely on pre and postsynaptic activity for synaptic changes have, to date, not been able to account for learning complex tasks that demand credit assignment in hierarchical networks. Here, we show that if synaptic plasticity is regulated by high-frequency bursts of spikes, then neurons higher in a hierarchical circuit can coordinate the plasticity of lower-level connections. Using simulations and mathematical analyses, we demonstrate that, when paired with short-term synaptic dynamics, regenerative activity in the apical dendrites, and synaptic plasticity in feedback pathways, a burst-dependent learning rule can solve challenging tasks that require deep network architectures. Our results demonstrate that well-known properties of dendrites, synapses, and synaptic plasticity are sufficient to enable sophisticated learning in hierarchical circuits.

2021-05-12

Nature Neuroscience (published)

doi.org

Variability in Brain Structure and Function Reflects Lack of Peer Support

Matthias Schurz

Lucina Q. Uddin

Philipp Kanske

Claus Lamm

Jérôme Sallet

Boris C. Bernhardt

Rogier B. Mars

Danilo Bzdok

Humans are a highly social species. Complex interactions for mutual support range from helping neighbors to building social welfare institut… (see more)ions. During times of distress or crisis, sharing life experiences within one’s social circle is critical for well-being. By translating pattern-learning algorithms to the UK Biobank imaging-genetics cohort (n = ~40 000 participants), we have delineated manifestations of regular social support in multimodal whole-brain measurements. In structural brain variation, we identified characteristic volumetric signatures in the salience and limbic networks for high- versus low-social support individuals. In patterns derived from functional coupling, we also located interindividual differences in social support in action–perception circuits related to binding sensory cues and initiating behavioral responses. In line with our demographic profiling analysis, the uncovered neural substrates have potential implications for loneliness, substance misuse, and resilience to stress.

2021-05-12

Cerebral Cortex (New York, NY) (published)

doi.org

Common limitations of performance metrics in biomedical image analysis

Annika Reinke

Matthias Eisenmann

Minu Dietlinde Tizabi

Carole H. Sudre

TIM RÄDSCH

Michela Antonelli

Tal Arbel

Spyridon Bakas

M. Jorge Cardoso

Veronika Cheplygina

Keyvan Farahani

Ben Glocker

DOREEN HECKMANN-NÖTZEL

Fabian Isensee

Pierre Jannin

Charles Kahn

Jens Kleesiek

Tahsin Kurc

Michal Kozubek

Bennett Landman … (see 15 more)

GEERT LITJENS

Klaus Maier-Hein

Anne Martel

Bjoern Menze

Henning Müller

Jens Petersen

Mauricio Reyes

Nicola Rieke

Bram Stieltjes

Ronald M. Summers

Sotirios A. Tsaftaris

Bram van Ginneken

Annette Kopp-Schneider

Paul Jäger

Lena Maier-Hein

2021-05-10

MIDL.io/2021/Conference/Short (poster)

openreview.net

How does hemispheric specialization contribute to human-defining cognition?

Gesa Hartwigsen

Yoshua Bengio

Danilo Bzdok

2021-05-10

Neuron (published)

doi.org

Optimizing Operating Points for High Performance Lesion Detection and Segmentation Using Lesion Size Reweighting

Brennan Nichyporuk

Justin Szeto

Douglas Arnold

Tal Arbel

There are many clinical contexts which require accurate detection and segmentation of all focal pathologies (e.g. lesions, tumours) in patie… (see more)nt images. In cases where there are a mix of small and large lesions, standard binary cross entropy loss will result in better segmentation of large lesions at the expense of missing small ones. Adjusting the operating point to accurately detect all lesions generally leads to oversegmentation of large lesions. In this work, we propose a novel reweighing strategy to eliminate this performance gap, increasing small pathology detection performance while maintaining segmentation accuracy. We show that our reweighing strategy vastly outperforms competing strategies based on experiments on a large scale, multi-scanner, multi-center dataset of Multiple Sclerosis patient images.

2021-05-10

MIDL.io/2021/Conference/Short (poster)

openreview.net

Phenotypical predictors of pregnancy-related restless legs syndrome and their association with basal ganglia and the limbic circuits

Natalia Chechko

Jeremy Lefort-Besnard

Tamme W. Goecke

Markus Frensch

Patricia Schnakenberg

Susanne Stickel

Danilo Bzdok

Restless legs syndrome (RLS) in pregnancy is a common disorder with a multifactorial etiology. A neurological and obstetrical cohort of 308 … (see more)postpartum women was screened for RLS within 1 to 6 days of childbirth and 12 weeks postpartum. Of the 308 young mothers, 57 (prevalence rate 19%) were identified as having been affected by RLS symptoms in the recently completed pregnancy. Structural and functional MRI was obtained from 25 of these 57 participants. A multivariate two-window algorithm was employed to systematically chart the relationship between brain structures and phenotypical predictors of RLS. A decreased volume of the parietal, orbitofrontal and frontal areas shortly after delivery was found to be linked to persistent RLS symptoms up to 12 weeks postpartum, the symptoms' severity and intensity in the most recent pregnancy, and a history of RLS in previous pregnancies. The same negative relationship was observed between brain volume and not being married, not receiving any iron supplement and higher numbers of stressful life events. High cortisol levels, being married and receiving iron supplements, on the other hand, were found to be associated with increased volumes in the bilateral striatum. Investigating RLS symptoms in pregnancy within a brain-phenotype framework may help shed light on the heterogeneity of the condition.

2021-05-10

Scientific Reports (published)

doi.org

Graph Attention Networks with Positional Embeddings

Liheng Ma

Reihaneh Rabbany

Adriana Romero

2021-05-08

Advances in Knowledge Discovery and Data Mining (published)

doi.org

arxiv.org

SigTran: Signature Vectors for Detecting Illicit Activities in Blockchain Transaction Networks