The current and future contribution of neuroimaging to the understanding of disorders of consciousness

Patients with disorders of consciousness (DoC) represent a group of severely brain-injured patients with varying capacities for consciousness in terms of both wakefulness and awareness. The current state-of-the-art for assessing these patients is through standardised behavioural examinations, but inaccuracies are com-monplace. Neuroimaging and electrophysiological techniques have revealed vast insights into the relation-ships between neural alterations, andcognitive and behavioural features of consciousness in patients with DoC. This has led to the establishment of neuroimaging paradigms for the clinical assessment of DoC patients. Here, we review selected neuroimaging findings on the DoC population, outlining key findings of the dys-function underlying DoC and presenting the current clinical utility of neuroimaging tools. We discuss that whilst individual brain areas play instrumental roles in generating and supporting consciousness, activation of these areas alone is not sufficient for conscious experience. Instead, for consciousness to arise, we need preserved thalamo-cortical circuits, in addition to sufficient connectivity between distinctly differentiated brain networks, underlined by connectivity both within, and between such brain networks. Finally, we present recent advances and future perspectives in computational methodologies applied to DoC, supporting the notion that progress in the science of DoC will be driven by a symbiosis of these data-driven analyses, and theory-driven research. Both perspectives will work in tandem to provide mechanistic insights contextual-ised within theoretical frameworks which ultimately inform the practice of clinical neurology. (c) 2023 The Authors. Published by Elsevier Masson SAS. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Automated summary

Patients with disorders of consciousness (DoC) have varying levels of wakefulness and awareness due to severe brain injury. Standardised behavioural examinations are commonly used to assess these patients, but they are often inaccurate. Neuroimaging has provided insights into the neural alterations associated with DoC, and has led to the development of neuroimaging paradigms for clinical assessment. However, consciousness cannot be solely attributed to the activation of specific brain areas, but rather requires the preservation of thalamo-cortical circuits and connectivity between different brain networks. Computational methodologies applied to DoC research can enhance our understanding and inform clinical practice.