Minimally conscious state or cortically mediated state?

Brain. 2018 Apr 1;141(4):949-960. doi: 10.1093/brain/awx324.

Abstract

Durable impairments of consciousness are currently classified in three main neurological categories: comatose state, vegetative state (also recently coined unresponsive wakefulness syndrome) and minimally conscious state. While the introduction of minimally conscious state, in 2002, was a major progress to help clinicians recognize complex non-reflexive behaviours in the absence of functional communication, it raises several problems. The most important issue related to minimally conscious state lies in its criteria: while behavioural definition of minimally conscious state lacks any direct evidence of patient's conscious content or conscious state, it includes the adjective 'conscious'. I discuss this major problem in this review and propose a novel interpretation of minimally conscious state: its criteria do not inform us about the potential residual consciousness of patients, but they do inform us with certainty about the presence of a cortically mediated state. Based on this constructive criticism review, I suggest three proposals aiming at improving the way we describe the subjective and cognitive state of non-communicating patients. In particular, I present a tentative new classification of impairments of consciousness that combines behavioural evidence with functional brain imaging data, in order to probe directly and univocally residual conscious processes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cerebral Cortex / physiopathology*
  • Consciousness Disorders* / classification
  • Consciousness Disorders* / pathology
  • Consciousness Disorders* / physiopathology
  • Humans
  • Neurology