Cortical Processing of Complex Auditory Stimuli during Alterations of Consciousness with the General Anesthetic Propofol

@article{Plourde2006CorticalPO,
  title={Cortical Processing of Complex Auditory Stimuli during Alterations of Consciousness with the General Anesthetic Propofol},
  author={Gilles Plourde and Pascal Belin and Daniel Chartrand and Pierre Olivier Fiset and Steven B. Backman and G. Xie and Robert J. Zatorre},
  journal={Anesthesiology},
  year={2006},
  volume={104},
  pages={448-457}
}
Background: The extent to which complex auditory stimuli are processed and differentiated during general anesthesia is unknown. The authors used blood oxygenation level–dependent functional magnetic resonance imaging to examine the processing words (10 per period; compared with scrambled words) and nonspeech human vocal sounds (10 per period; compared with environmental sounds) during propofol anesthesia. Methods: Seven healthy subjects were tested. Propofol was given by a computer-controlled… 
Cortical Responses to Vowel Sequences in Awake and Anesthetized States: A Human Intracranial Electrophysiology Study.
TLDR
Intracranial electroencephalography is used to examine cortical responses to vowel sequences during induction of general anesthesia with propofol to identify putative biomarkers of LOC and serve as a foundation for future investigations of altered sensory processing.
Auditory Predictive Coding across Awareness States under Anesthesia: An Intracranial Electrophysiology Study
TLDR
Changes in the activation of cortical networks involved in auditory novelty detection over short (local deviant) and long (global deviance) time scales associated with sedation and LOC under propofol anesthesia are investigated.
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TLDR
Perceptual learning was not induced by repetitive auditory stimulation during anesthesia, which may indicate that perceptual learning requires top-down processing, which is suppressed by the anesthetic.
Electrocorticographic delineation of human auditory cortical fields based on effects of propofol anesthesia
The sensory thalamus and cerebral motor cortex are affected concurrently during induction of anesthesia with propofol: a case series with intracranial electroencephalogram recordings
TLDR
Intacranial electroencephalogram recordings from the ventroposterolateral nucleus of the thalamus and from the motor cortex during induction of anesthesia in three patients were obtained to study the time course of the alterations of cortical and thalamic function.
The brain-bases of responsiveness variability under moderate anaesthesia
TLDR
For the first time, responsiveness variability during propofol anaesthesia relates to inherent differences in brain function and structure within the executive control network, which can be predicted prior to sedation.
Regional entropy of functional imaging signals varies differently in sensory and cognitive systems during propofol-modulated loss and return of behavioral responsiveness
TLDR
The differential changes of entropy in the sensory and high-order cognitive systems associated with losing and regaining overt responsiveness are consistent with the notion of “disconnected consciousness”, in which a complete sensory-motor disconnection from the environment occurs with preserved internal mentation.
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