1. Reclassifying stroke lesion anatomy
- Author
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Geraint Rees, Parashkev Nachev, Robert Gray, Hans Rolf Jäger, Tianbo Xu, Amy Nelson, Jorge Cardoso, Sebastien Ourselin, Anna K. Bonkhoff, and Ashwani Jha
- Subjects
Cognitive Neuroscience ,media_common.quotation_subject ,t-SNE, t-stochastic neighbour embedding ,Fidelity ,Experimental and Cognitive Psychology ,Brain imaging ,Machine learning ,computer.software_genre ,DWI, diffusion-weighted imaging ,Humans ,Limit (mathematics) ,Simplicity ,media_common ,Ground truth ,Brain Mapping ,business.industry ,Dimensionality reduction ,Representation (systemics) ,Lesion anatomy ,Brain ,Cognition ,Outcome (probability) ,Stroke ,NMF, non-negative matrix factorization ,Neuropsychology and Physiological Psychology ,Clinical Neuroanatomy ,BA, Brodmann Area ,Artificial intelligence ,Psychology ,business ,computer ,Lesion–deficit prediction - Abstract
Cognitive and behavioural outcomes in stroke reflect the interaction between two complex anatomically-distributed patterns: the functional organization of the brain and the structural distribution of ischaemic injury. Conventional outcome models—for individual prediction or population-level inference—commonly ignore this complexity, discarding anatomical variation beyond simple characteristics such as lesion volume. This sets a hard limit on the maximum fidelity such models can achieve. High-dimensional methods can overcome this problem, but only at prohibitively large data scales. Drawing on one of the largest published collections of anatomically-registered imaging of acute stroke—N = 1333—here we use non-linear dimensionality reduction to derive a succinct latent representation of the anatomical patterns of ischaemic injury, agglomerated into 21 distinct intuitive categories. We compare the maximal predictive performance it enables against both simpler low-dimensional and more complex high-dimensional representations, employing multiple empirically-informed ground truth models of distributed structure–outcome relationships. We show our representation sets a substantially higher ceiling on predictive fidelity than conventional low-dimensional approaches, but lower than that achievable within a high-dimensional framework. Where descriptive simplicity is a necessity, such as within clinical care or research trials of modest size, the representation we propose arguably offers a favourable compromise of compactness and fidelity.
- Published
- 2021