ADRD

Alzheimer’s Disease and Related Dementia (ADRD)

normal brain v dementia brain

We are among the first groups showing importance of alteration of the resting-state fMRI brain network in Alzheimer’s disease (AD) (Khazaee et al., 2015). We demonstrated alteration of the brain network in early stages of AD and mild cognitive impairment (MCI) (Hojjati et al., 2019). We demonstrated that integrating multimodal neuroimaging data (MRI, fMRI, and PET) with AI can predict neuropsychological scores in AD, suggesting a robust framework for early disease detection (Hojjati et al., 2021).We further identified key biomarkers and brain regions associated with cognitive decline in AD, providing insights into disease progression and potential therapeutic targets (Hojjati et al., 2024).

Importance of Key biomarkers
Importance of key biomarkers in predicting The Alzheimer’s Disease Assessment Scale (ADAS) scores across diagnostic groups: Amyloid-β from PET (top-left), average gray matter thickness from MRI (top-right), and mean diffusivity from DTI (bottom). (Hojjati et al., 2024).
Abbreviations: AD: Alzheimer’s Disease; CN: Cognitively Normal; MCI: Mild Cognitive Impairment

In an ongoing project, we are developing, training, and testing advanced 3D CNN-based deep learning models to predict brain age from MRI scans in a large cohort of cognitively normal (CN) subjects. By comparing the difference between chronological and predicted brain age—referred to as the “age gap”—we aim to demonstrate that this gap is significantly larger in subjects with neurodegenerative diseases such as AD, LBD, and Parkinson’s disease (PD). This suggests accelerated brain aging associated with these conditions, enhancing our understanding of age-related neuroanatomical changes in neurodegenerative diseases.

Predicted brain age
A simple 3D CNN-based deep learning model to predict brain age from the MRI scans.
Brain aging
Average saliency maps generated by the deep learning model, highlighting key brain regions influential in predicting brain age.
Brain scans sowing AD & LB v normal aging

In an ongoing project, we are using deep learning–based brain-age modeling to characterize neurodegeneration in Alzheimer’s disease (AD) with Lewy body (LB) co-pathology. We develop and validate 3D CNN models on large, well-characterized neuroimaging cohorts to learn patterns of normative brain aging from structural MRI. We then apply these models to biomarker-defined clinical cohorts to quantify deviations from typical aging (i.e., brain age “gap”) across AD and LB pathophysiological profiles. Using interpretable AI methods and complementary region-of-interest analyses, we aim to identify neuroanatomical signatures associated with co-pathology and determine how these imaging-derived measures relate to longitudinal cognitive trajectories. Ultimately, this work seeks to refine biomarker-informed stratification and improve our understanding of heterogeneity in AD-related neurodegeneration.

Person in MEG machine
In an ongoing project, we use MEG to improve diagnostic accuracy and develop targeted interventions for Alzheimer’s Disease and Related Dementia (ADRD).

Related Publications

Seeing beyond the symptoms: Biomarkers and brain regions linked to cognitive decline in Alzheimer’s disease

Hojjati SH, Babajani-Feremi A; Alzheimer’s Disease Neuroimaging Initiative. Seeing beyond the symptoms: biomarkers and brain regions linked to cognitive decline in Alzheimer’s disease. Front Aging Neurosci. 2024 May 15;16:1356656. doi: 10.3389/fnagi.2024.1356656. PMID: 38813532; PMCID: PMC11135344.

Prediction and Modeling of Neuropsychological Scores in Alzheimer’s Disease Using Multimodal Neuroimaging Data and Artificial Neural Networks

Hojjati SH, Babajani-Feremi A; Alzheimer’s Disease Neuroimaging Initiative. Prediction and Modeling of Neuropsychological Scores in Alzheimer’s Disease Using Multimodal Neuroimaging Data and Artificial Neural Networks. Front Comput Neurosci. 2022 Jan 6;15:769982. doi: 10.3389/fncom.2021.769982. PMID: 35069161; PMCID: PMC8770936.

Identification of the Early Stage of Alzheimer’s Disease Using Structural MRI and Resting-State fMRI

Hojjati, S.H., Ebrahimzadeh, A., & Babajani-Feremi, A. (2019). Identification of the Early Stage of Alzheimer’s Disease Using Structural MRI and Resting-State fMRI. Frontiers in Neurology, 10.

Predicting conversion from MCI to AD using resting-state fMRI, graph theoretical approach and SVM

Hojjati SH, Ebrahimzadeh A, Khazaee A, Babajani-Feremi A; Alzheimer’s Disease Neuroimaging Initiative. Predicting conversion from MCI to AD using resting-state fMRI, graph theoretical approach and SVM. J Neurosci Methods. 2017 Apr 15;282:69-80. doi: 10.1016/j.jneumeth.2017.03.006. Epub 2017 Mar 9. PMID: 28286064.

Application of advanced machine learning methods on resting-state fMRI network of mild cognitive impairment and Alzheimer’s disease

Khazaee A, Ebrahimzadeh A, Babajani-Feremi A. Application of advanced machine learning methods on resting-state fMRI network for identification of mild cognitive impairment and Alzheimer’s disease. Brain Imaging Behav. 2016 Sep;10(3):799-817. doi: 10.1007/s11682-015-9448-7. PMID: 26363784.

Application of Pattern Recognition and Graph Theoretical Approaches to Analysis of Brain Network in Alzheimer’s Disease

Khazaee, Ali, Ebrahimzadeh, Ata, Babajani-Feremi, Abbas. Application of Pattern Recognition and Graph Theoretical Approaches to Analysis of Brain Network in Alzheimer’s Disease. Journal of Medical Imaging and Health Informatics. 2015 Nov; 5(6):1145-1155. doi: 10.1166.

Identifying patients with Alzheimer’s disease using resting-state fMRI and graph theory

Khazaee A, Ebrahimzadeh A, Babajani-Feremi A. Identifying patients with Alzheimer’s disease using resting-state fMRI and graph theory. Clin Neurophysiol. 2015 Nov;126(11):2132-41. doi: 10.1016/j.clinph.2015.02.060. Epub 2015 Apr 1. PMID: 25907414.