INTRODUCTION: Machine learning (ML) has been extremely successful in identifying key features from high-dimensional datasets and executing complicated tasks with human expert levels of accuracy or greater.
METHODS: We summarize and critically evaluate current applications of ML in dementia research and highlight directions for future research.
RESULTS: We present an overview of ML algorithms most frequently used in dementia research and highlight future opportunities for the use of ML in clinical practice, experimental medicine, and clinical trials. We discuss issues of reproducibility, replicability and interpretability and how these impact the clinical applicability of dementia research. Finally, we give examples of how state-of-the-art methods, such as transfer learning, multi-task learning, and reinforcement learning, may be applied to overcome these issues and aid the translation of research to clinical practice in the future.
DISCUSSION: ML-based models hold great promise to advance our understanding of the underlying causes and pathological mechanisms of dementia.
This paper was the product of a DEMON Network state of the science symposium entitled “Harnessing Data Science and AI in Dementia Research” funded by Alzheimer’s Research UK. JMR and DJL are supported by Alzheimer’s Research UK and the Alan Turing Institute/Engineering and Physical Sciences Research Council (EP/N510129/1). DJL has also received funding from the National Institute for Health Research (NIHR) Applied Research Collaboration (ARC) South West Peninsula, National Health and Medical Research Council (NHMRC), JP Moulton Foundation, National Institute on Aging/National Institutes of Health (RF1AG055654), Alan Turing Institute/Engineering and Physical Sciences Research Council (EP/N510129/1). This work was additionally supported by Alzheimer’s Research UK (MB, CJ), European Union INTERREG VA Programme (MB), Dr George Moore Endowment for Data 31 Science at Ulster University (MB), National Institute for Health and Care Research Bristol Biomedical Research Centre (CJ), Fonds de recherche du Québec Santé - Chercheur boursiers Junior 1 (AB), Canadian Consortium for Neurodegeneration in Aging and the Courtois Foundation (AB, NC), The Motor Neurone Disease Association Fellowship (Al Khleifat/Oct21/975-799) (AAK), ALS Association Milton Safenowitz Research Fellowship (grant number 22-PDF 609. doi:10.52546/pc.gr.150909) (AAK), NIHR Maudsley Biomedical Research Centre (AAK), The Darby Rimmer Foundation (AAK), UKRI Future Leaders Fellowship (MR/S03546X/1) (CS), E-DADS project (EU JPND) (CS), EuroPOND project (EU Horizon 2020, no. 666992) (CS). SJM is funded by the Edmond and Lily Safra Early Career Fellowship Program and the UK Dementia Research Institute, which receives its funding from UK DRI Ltd, funded by the UK Medical Research Council, Alzheimer's Society and Alzheimer's Research UK.
- artificial intelligence
- machine learning
- deep learning
- supervised learning
- unsupervised learning
- semi-supervised learning
- methods optimization
- clinical utility