The specificity of thalamic alterations in Korsakoff’s syndrome: Implications for the study of amnesia

• KS is a study model to specify the role of the thalamus in amnesia. • Thalamic nuclei can be measured in vivo with high-field MRI or multimodal imaging. • Disconnection in anterior nuclei cascades into atrophy triggering amnesia in KS. • Thalamus must be considered within brain circuits, in an integrative approach. • Neuroimaging markers of thiamine, inflammation and acetylcholine should be tested. The pathophysiological mechanisms behind amnesia are still unknown. Recent literature, through the study of patients with Alcohol Use Disorder with and without Korsakoff’s syndrome, increasingly shows that physiological alterations to the thalamus have an important role in the development of amnesia. This review gives an overview of neuropsychological, neuropathological and neuroimaging contributions to the understanding of Korsakoff’s syndrome, highlighting the central role of the thalamus in this amnesia. The thalamus being a multi-nucleus structure, the limitations regarding the loci, nature and alterations to specific nuclei are discussed, along with potential solutions. Finally, future directions for clinical research are laid out to unravel the intricacies inherent to amnesia. They consider the need to evaluate the physiological role of the thalamus, not only as an entity but also as part of a brain circuit through a more integrative approach.