Majd Abdallah

Dr. Majd Abdallah

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 September 2022 in eLife
Verified
Journal Article
Open access
MAMajd Abdallah
Majd Abdallah
GZGaston E Zanitti
Gaston E Zanitti
VIValentin Iovene
Valentin Iovene
DWDemian Wassermann
Demian Wassermann
The lateral prefrontal cortex (LPFC) of humans enables flexible goal-directed behavior. However, its functional organization remains actively debated after decades of research. Moreover, recent efforts aiming to map the LPFC through meta-analysis are limited, either in scope or in the inferred specificity of structure-function associations. These limitations are in part due to the limited expressiveness of commonly-used data analysis tools, which restricts the breadth and complexity of questions that can be expressed in a meta-analysis. Here, we adopt NeuroLang, a novel approach to more expressive meta-analysis based on probabilistic first-order logic programming, to infer the organizing principles of the LPFC from 14,371 neuroimaging studies. Our findings reveal a rostrocaudal and a dorsoventral gradient, respectively explaining the most and second most variance in meta-analytic connectivity across the LPFC. Moreover, we identify a unimodal-to-transmodal spectrum of coactivation patterns along with a concrete-to-abstract axis of structure-function associations extending from caudal to rostral regions of the LPFC. Finally, we infer inter-hemispheric asymmetries along the principal rostrocaudal gradient, identifying hemisphere-specific associations with topics of language, memory, response inhibition, and sensory processing. Overall, this study provides a comprehensive meta-analytic mapping of the LPFC, grounding future hypothesis generation on a quantitative overview of past findings.

25 March 2026 in Nature Communications
Verified
Journal Article
Open access
PDF file
MAMajd Abdallah
Majd Abdallah
Sigve NakkenSigve Nakken
Sigve Nakken
MGMikaël Georges
Mikaël Georges
MBMariska Bierkens
Mariska Bierkens
JGJohanna Galvis
Johanna Galvis
MNMacha Nikolski
Macha Nikolski
Patient recruitment remains a major bottleneck in clinical trials, calling for scalable and automated solutions. We present TrialMatchAI, an AI-powered recommendation system that automates patient-to-trial matching by processing heterogeneous clinical data, including structured records and unstructured physician notes. Built on fine-tuned, open-source large language models (LLMs) within a retrieval-augmented generation framework, TrialMatchAI ensures transparency and reproducibility and maintains a lightweight deployment footprint suitable for clinical environments. The system normalizes biomedical entities, retrieves relevant trials using a hybrid search strategy combining lexical and semantic similarity, re-ranks results, and performs criterion-level eligibility assessments using medical Chain-of-Thought reasoning. This pipeline delivers explainable outputs with traceable decision rationales. In real-world validation, 92% of oncology patients had at least one relevant trial retrieved within the top 20 recommendations. Evaluation across synthetic and real clinical datasets confirmed state-of-the-art performance, with expert assessment validating over 90% accuracy in criterion-level eligibility classification - particularly excelling in biomarker-driven matches. Designed for modularity and privacy, TrialMatchAI supports Phenopackets-standardized data, enables secure local deployment, and allows seamless replacement of LLM components as more advanced models emerge. By enhancing efficiency, interpretability and offering lightweight, open-source deployment, TrialMatchAI provides a scalable solution for AI-driven clinical trial matching in precision medicine.

28 October 2022 in Biomedicines
Verified
Journal Article
Open access
PDF file
LJLouise Jakubiec
Louise Jakubiec
VCValentine Chirokoff
Valentine Chirokoff
MAMajd Abdallah
Majd Abdallah
ESErnesto Sanz-Arigita
Ernesto Sanz-Arigita
MDMaud Dupuy
Maud Dupuy
MFMelina Fatseas
Melina Fatseas
Deficits in neurocognitive functioning are trait-like vulnerabilities that have been widely studied in persons with substance use disorders (SUD), but their role in the craving–use association and relapse vulnerability remains poorly understood. The main objectives of this study were to examine whether executive capacities moderate the magnitude of the craving–substance use relationship, and if this influence is correlated with the functional connectivity of cerebral networks, combining rsfMRI examinations and ecological momentary assessment (EMA). Eighty-six patients beginning outpatient treatment for alcohol, tobacco or cannabis addiction and 40 healthy controls completed neuropsychological tests followed by EMA to collect real-time data on craving. Fifty-four patients and 30 healthy controls also completed a resting-state fMRI before the EMA. Among the patients with SUD, better verbal fluency and resistance to interference capacities were associated with a greater propensity to use substances when the individual was experiencing craving. Preliminary rsfMRI results identified specific networks that interacted with executive performance capacities to influence the magnitude of the craving–use association. Individuals with better executive functioning may be more prone to relapse after craving episodes. Specifically, better resistance to interference and cognitive flexibility skills may reduce attention to distracting stimuli, leading to a greater awareness of craving and susceptibility to use substances.

27 December 2021 in Biology
Verified
Journal Article
Open access
PDF file
YRYolaine Rabat
Yolaine Rabat
SCSandra CHANRAUD
Sandra CHANRAUD
MAMajd Abdallah
Majd Abdallah
ISIgor Sibon
Igor Sibon
SBSylvie Berthoz
Sylvie Berthoz
Chronic tobacco smoking remains a major health problem worldwide. Numerous smokers wish to quit but most fail, even if they are helped. The possibility of identifying neuro-biomarkers in smokers at high risk of relapse could be of incredible progress toward personalized prevention therapy. Our aim is to provide a scoping review of this research topic in the field of Magnetic Resonance Imaging (MRI) and to review the studies that investigated if MRI defined markers predicted smoking cessation treatment outcome (abstainers versus relapsers). Based on the available literature, a meta-analysis could not be conducted. We thus provide an overview of the results obtained and take stock of methodological issues that will need to be addressed to pave the way toward precision medicine. Based on the most consistent findings, we discuss the pivotal role of the insula in light of the most recent neurocognitive models of addiction.

28 February 2022 in bioRxiv
Verified
Preprint
Open access
PDF file
MAMajd Abdallah
Majd Abdallah
VIValentin Iovene
Valentin Iovene
GZGaston Zanitti
Gaston Zanitti
DWDemian Wassermann
Demian Wassermann
Inferring reliable brain-behavior associations requires synthesizing evidence from thousands of functional neuroimaging studies through meta-analysis. However, existing meta-analysis tools are limited to investigating simple neuroscience concepts and expressing a restricted range of questions. Here, we expand the scope of neuroimaging meta-analysis by designing NeuroLang: a domain-specific language to express and test hypotheses using probabilistic first-order logic programming. By leveraging formalisms found at the crossroads of artificial intelligence and knowledge representation, NeuroLang provides the expressivity to address a larger repertoire of hypotheses in a meta-analysis, while seamlessly modelling the uncertainty inherent to neuroimaging data. We demonstrate the language’s capabilities in conducting comprehensive neuroimaging meta-analysis through use-case examples that address questions of structure-function associations. Specifically, we infer the specific functional roles of three canonical brain networks, support the role of the visual word-form area in visuospatial attention, and investigate the heterogeneous organization of the fronto-parietal control network.

23 January 2022 in bioRxiv
Verified
Preprint
Open access
PDF file
MAMajd Abdallah
Majd Abdallah
GZGaston Zanitti
Gaston Zanitti
VIValentin Iovene
Valentin Iovene
DWDemian Wassermann
Demian Wassermann
The human lateral prefrontal cortex (LPFC) enables flexible goal-directed behavior. Yet, its organizing principles remain actively debated despite decades of research. Meta-analysis efforts to map the LPFC have either been restricted in scope or suffered from limited expressivity in meta-analysis tools. The latter short-coming hinders the complexity of questions that can be expressed in a meta-analysis and hence limits the specificity of structure-function associations. Here, we adopt NeuroLang, a novel approach to meta-analysis based on first-order probabilistic logic programming, to infer the organizing principles of the LPFC with greater specificity from 14,371 neuroimaging publications. Our results reveal a rostrocaudal and a dorsoventral gradient, respectively explaining the most and second-most variance in whole-brain meta-analytic connectivity in the LPFC. Moreover, we find a cross-study agreement on a spectrum of increasing abstraction from caudal to rostral LPFC both in specific network connectivity and structure-function associations that supports a domain-general role for the mid-LPFC. Furthermore, meta-analyzing inter-hemispheric asymmetries along the rostrocaudal gradient reveals specific associations with topics of language, memory, response inhibition, and error processing. Overall, we provide a comprehensive mapping of the organizing principles of task-dependent activity in the LPFC, grounding future hypothesis generation on a quantitative overview of past findings.