Assessing specificity testing in Lesion Network Mapping

Lesion Network Mapping (LNM) is a framework that maps symptom-related brain circuits by projecting lesion locations onto a normative connectome. However, recent investigations have questioned the biological interpretation and specificity of the circuits obtained using this method, as many LNM maps display high similarity across conditions that are clinically unrelated.

To address this issue, specificity testing has been proposed as a crucial step to ensure that the circuits identified are truly specific to the symptom being studied. The proponents argue that this step was overlooked in the original LNM investigations. Nonetheless, sensitivity testing, specificity testing, case-control LNM, permutation of group labels, and symptom-based LNM all involve operations on the same connectivity matrix C. This article delves deeper into the concept of specificity testing within LNM, clarifies its relationship to other LNM procedures and adaptations, and investigates the recurring appearance of LNM specificity networks across various studies.

By addressing these considerations, we gain a better understanding of the limitations of LNM in terms of disease-specificity and inspire the creation of new methods to identify brain circuits responsible for psychiatric and neurological disorders.