Knowledge Vault 3/89 - G.TEC BCI & Neurotechnology Spring School 2024 - Day 9
Cognition in DOC patients: assessment and management
Caroline Schnakers, Casa Colina Hospital (USA)
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Concept Graph & Resume using Claude 3 Opus | Chat GPT4 | Llama 3:

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follow commands mentally. 9] J --> K[CMD patients perform complex
cognitive tasks. 10] J --> L[CMD distinct from locked-in syndrome. 11] J --> M[Thalamocortical, mesocircuit disruptions
may underlie CMD. 12] J --> N[CMD terminology confusion for
families, researchers. 13] A --> O[EEG preferred for covert
consciousness detection. 14] O --> P[Mental imagery EEG detects
command-following, cognition. 15] O --> Q[Early EEG identifies preserved
cognition, better prognosis. 16] O --> R[EEG markers for language,
attention, memory needed. 17] O --> S["Own name" EEG reveals
attention, prognostic value. 18] O --> T[Tone counting EEG captures
vigilance variability. 19] A --> U[Ultrasonic thalamic stimulation may
promote recovery. 20] U --> V[Case studies: ultrasound may
lead to meaningful recovery. 21] U --> W[Controlled ultrasound trials underway
for efficacy, mechanisms. 22] U --> X[Ultrasound may enhance arousal,
attention: EEG correlates needed. 23] A --> Y[Home EEG explored for
brain-computer interfaces. 24] Y --> Z[Home EEG may enable
remote cognitive rehab. 25] A --> AA[Future stimulation targets: basal
ganglia for motor, cognitive deficits. 26] A --> AB[Exciting progress in diagnosis,
prognosis, novel therapies. 27] A --> AC[Advances made, but work
remains for long-term outcomes. 28] A --> AD[Ethical implications require ongoing consideration. 29] A --> AE[Updated textbook resource for
clinicians, trainees. 30] class A,B,C schnakers; class D,E,F,AB,AC,AD,AE consciousness; class G,H,I assessment; class J,K,L,M,N dissociation; class O,P,Q,R,S,T,Y,Z eeg; class U,V,W,X ultrasound; class AA future;


1.- Caroline Schnakers is a leading researcher in the field of disorders of consciousness, building on the work of Steven Laureys.

2.- Patients with severe brain injury progress from coma to vegetative state, minimally conscious state, and emergence from disorder of consciousness.

3.- Misdiagnosis rates for disorders of consciousness remain around 40%, despite increased awareness of the need for sensitive assessment tools.

4.- The Coma Recovery Scale-Revised is a sensitive tool for detecting signs of consciousness, superior to the commonly used Glasgow Coma Scale.

5.- Guidelines from the American Academy of Neurology and European Academy of Neurology provide recommendations for clinical management of disorders of consciousness.

6.- Spasticity and pain are major confounders that can prevent detection of signs of consciousness in brain-injured patients.

7.- The Nociception Coma Scale-Revised helps assess pain in patients with disorders of consciousness and monitor treatment effectiveness.

8.- Spasticity progresses differently over time depending on injury etiology - more rapid contractures in hypoxic-ischemic versus traumatic brain injury.

9.- Functional neuroimaging shows some seemingly unresponsive patients can follow commands through mental imagery, indicating "cognitive-motor dissociation".

10.- Patients demonstrating "cognitive-motor dissociation" appear able to perform complex cognitive tasks like language comprehension, working memory, executive functions.

11.- The clinical entity of "cognitive-motor dissociation" is distinct from locked-in syndrome, which has more circumscribed brainstem lesions and eye movement.

12.- Limited studies suggest thalamocortical and mesocircuit disruptions may underlie the dissociation between cognitive capacity and motor output.

13.- Lack of expert consensus on terminology for this "cognitive-motor dissociation" phenomenon leads to confusion for families and researchers.

14.- Surveys show most clinicians now use EEG rather than fMRI to detect covert consciousness, but implementation barriers remain.

15.- Mental imagery EEG paradigms are validated for detecting command-following and higher cognition in patients who are unresponsive at the bedside.

16.- Standardized EEG testing early after brain injury can identify patients with preserved cognition and better prognosis despite unresponsive exam.

17.- Development of EEG markers of specific cognitive functions like language, attention, working memory in this population remains an unmet need.

18.- The "own name" EEG paradigm reveals basic attention and prognostic value based on brain response to one's name versus unfamiliar names.

19.- A novel EEG attention paradigm involving tone counting over repeated blocks captures variability in patients' vigilance over short timescales.

20.- Non-invasive ultrasonic thalamic stimulation shows promise for promoting recovery in chronic disorders of consciousness, but replication is needed.

21.- Case studies suggest ultrasound may lead to meaningful recovery in some patients, but distinguishing treatment effects from spontaneous recovery is difficult.

22.- Controlled trials of ultrasonic stimulation (versus sham) are underway to better establish efficacy, optimal dosing, and neurophysiological mechanisms.

23.- Behavioral assessments suggest ultrasound may enhance patients' arousal and visual attention; EEG correlates of cognitive effects should be examined.

24.- Home-based EEG systems are being explored to expand access to brain-computer interface technology for severely disabled patients.

25.- Accessible, user-friendly, cost-effective home EEG may enable remote cognitive rehabilitation, but barriers like visual impairment must be considered.

26.- Future brain stimulation targets beyond the thalamus, like the basal ganglia, may address specific motor or cognitive deficits at different recovery stages.

27.- The field is at an exciting point with many researchers making strides in diagnosis, prognosis, and novel therapies for these challenging conditions.

28.- Increased awareness, validated assessment tools, and management guidelines are major steps forward, but much work remains to improve long-term outcomes.

29.- Ethical implications around life-sustaining care and communication with patients require ongoing consideration as the science and practice evolve.

30.- The 3rd edition textbook "Coma and Disorders of Consciousness" provides an up-to-date resource on assessment and management for clinicians and trainees.

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