Neural correlates of consciousness and related disorders: From phenotypic descriptors of behavioral and relative consciousness to cortico-subcortical circuitry.
J-J Lemaire, B Pontier, R Chaix, Y El Ouadih, T Khalil, D Sinardet, V Achim, A Postelnicu, J Coste, V Germain, C Sarret, A Sontheimer
Neuro-Chirurgie February 2022 DOI: 10.1016/j.neuchi.2021.05.003 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Topics | Default mode network |
| Keywords | Behavior Disorders of consciousness FMRI |
| Key findings | The review argues that consciousness is relative and specific to each individual, cannot be separated from behavior, and involves metapractic and metagnostic aspects. It outlines three DoC types (coma, vegetative state/unresponsive wakefulness, minimally conscious state) and proposes neural correlates including two wakefulness pathways and cortico-subcortical circuitry, with cortical networks such as the global workspace and default mode network. The authors contend that network dynamics, including anticorrelations like decreased posterior cingulate-precuneus activity during attentional tasks, reflect consciousness, and they expect therapeutic progress from advances in DoC pathophysiology. |
Abstract
We report a review of medical aspects of the consciousness. The behavioral dimension, phenotypic descriptors, relative consciousness and neural correlates of consciousness and related disorders were addressed successively in a holistic and chronological approach. Consciousness is relative, specific to each individual across time and space. Historically defined as the perception of the self and the environment, it cannot be separated from behaviors, entailing an idea of conscious behavior with metapractic and metagnostic aspects. Observation of spontaneous and evoked overt behavior distinguishes three main types of disorder of consciousness (DoC): coma, vegetative state or unresponsive wakefulness, and minimally conscious or relationally impoverished state. Modern functional exploration techniques, such as imaging, increase the understanding of DoCs and consciousness. Whether consciousness is a superior function and/or an instrumental function is discussed. Neural correlates can be subdivided into two wakefulness pathways (superior thalamic cholinergic and inferior extra-thalamic), and cortico-subcortical circuitry. The deep brain structures are those described in the well-known sensorimotor, associative and limbic loops, as illustrated in the mesolimbic model of DoC. The cortices can be segregated into several overlapping networks: (1) a global workspace including thalamo-cortical loops; (2) the default mode network (DMN) and related intrinsic connectivity networks (i.e., central executive, medial DMN and salience networks); (3) a 3-fold network comprising the fronto-parietal control system and its dorsal and ventral attentional sub-networks, the fronto-parietal executive control network, and the cingulo-opercular salience network; (4) the internal and external cortices, respectively medial, turned toward the self, and lateral, turned toward the environment. The network dynamics is the reflection of consciousness, notably anticorrelations such as the decrease in activity of the posterior cingulate-precuneus regions during attentional tasks. Thanks to recent advances in DoC pathophysiology, further significative therapeutic progress is expected, taking into account the societal context. This depends notably on the dissemination of medical knowledge and its transfer to a wider public.
Comparable studies
Other narrative reviews on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| The Brain's Default Mode Network | 2015 | Review | |
| Default Mode Network Activity and Connectivity in Psychopathology | 2012 | Review | |
| 20 years of the default mode network: A review and synthesis | 2023 | Review | |
| On the relationship between the “default mode network” and the “social brain” | 2012 | Review | |
| The default mode network and social understanding of others: what do brain connectivity studies tell us Healthy subjects, with some studies on patients with autism and psychopathy | 2014 | Review |
Citations in the library
Cites 21
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- Breakdown of within- and between-network Resting State Functional Magnetic Resonance Imaging Connectivity during Propofol-induced Loss of Consciousness Anesthesiology September 30, 2010
- Two Distinct Neuronal Networks Mediate the Awareness of Environment and of Self Journal of Cognitive Neuroscience June 1, 2010
- A thalamic reticular networking model of consciousness Theoretical Biology and Medical Modelling March 30, 2010
- Studying the Well-Trained Mind Science October 2, 2003
and 16 more in the library