The End Of Knowledge - Vault 3 - G.TEC BCI & Neurotechnology Spring School 2024 - Day 9

graph LR classDef laureys fill:#f9d4d4, font-weight:bold, font-size:14px; classDef consciousness fill:#d4f9d4, font-weight:bold, font-size:14px; classDef disorders fill:#d4d4f9, font-weight:bold, font-size:14px; classDef assessment fill:#f9f9d4, font-weight:bold, font-size:14px; classDef interventions fill:#f9d4f9, font-weight:bold, font-size:14px; classDef ethics fill:#d4f9f9, font-weight:bold, font-size:14px; A[Steven Laureys] --> B[Laureys: neurologist, brain scientist
studying consciousness disorders. 1] A --> C[Consciousness: huge scientific challenge,
no explanatory theory. 3] C --> D[Consciousness: wakefulness and
awareness dimensions. 3] A --> E[Laureys' team: diverse
consciousness studies. 2] A --> F[Tools: PET, MRI, EEG,
TMS assess brain function. 4] A --> G[Repeated standardized behavioral
assessments avoid misdiagnosis. 5] G --> H[SECONDs: practical consciousness
assessment scale. 6] A --> I[Consciousness spectrum: coma to
locked-in syndrome. 7] I --> J[Cognitively-motor dissociation: awareness not
apparent behaviorally. 8] A --> K[fMRI mental imagery reveals
covert awareness, enables communication. 9] K --> L[fMRI paradigms challenging clinically,
EEG-BCI attractive bedside. 10] L --> M[Mindbeagle: first commercial EEG-BCI
for consciousness disorders. 11] A --> N[Other communication methods impractical
clinically. 12] A --> O[BCI challenges: false negatives,
positives, artifacts, damage. 13] O --> P[Cross-validation with neuroimaging, EEG
increases BCI confidence. 14] A --> Q[Circadian rhythms, arousal windows
impact BCI success. 15] A --> R[Language impairments confound awareness
assessments in MCS. 16] A --> S[Functional connectivity within, between
networks critical for consciousness. 17] S --> T[Precuneus: critical hub in
posterior parietal cortex. 18] S --> U[Machine learning classifiers distinguish
unresponsive from MCS. 19] A --> V[Covert awareness predicts better
long-term outcomes. 20] A --> W[Methods explored to facilitate
consciousness recovery. 21] W --> X[Zolpidem, apomorphine paradoxically increase
responsiveness, modulate mesocircuit. 22] A --> Y[Ethical issues critical assessing
non-communicative patients. 23] Y --> Z[Pain perception intact in MCS,
warrants routine analgesia. 24] A --> AA[Locked-in majority have positive
QoL, need communication tech. 25] A --> AB[Families prioritize information, involvement,
psychosocial support. 26] A --> AC[Media QoL portrayals inaccurate,
more research needed. 27] A --> AD[Risks, benefits weighed for
invasive interventions like DBS. 28] A --> AE[Non-invasive neuromodulation promising,
more clinical use likely. 29] A --> AF[Recovery trajectory varies, late
improvement possible. 30] class A,B,E laureys; class C,D consciousness; class F,G,H,I,J,K,L,M,N,O,P,Q,R disorders; class S,T,U,V assessment; class W,X,AE,AF interventions; class Y,Z,AA,AB,AC,AD ethics;

Resume:

1.- Steven Laureys is a well-known neurologist and brain scientist studying disorders of consciousness in Belgium and Canada using various technologies.

2.- Laureys and his team study consciousness in patients with brain injury, concussion, astronauts in zero gravity, artists, Buddhist monks, and more.

3.- Consciousness is a huge challenge to study scientifically with no explanatory theory, but can be reduced to wakefulness and awareness dimensions.

4.- Laureys' team uses PET, MRI, EEG, TMS and other tools to assess residual brain function in coma and related disorders.

5.- Repeated standardized behavioral assessments like the Coma Recovery Scale are critical to avoid misdiagnosis of patient awareness.

6.- The Simplified Evaluation of Consciousness (SECONDs) scale was developed as a more practical tool than the Coma Recovery Scale.

7.- Patients can show a spectrum of consciousness from coma to unresponsive wakefulness, minimally conscious state (MCS), emergence, and locked-in syndrome.

8.- Neuroimaging sometimes reveals cognitively-motor dissociation - evidence of awareness not apparent from behavioral assessment alone in some unresponsive patients.

9.- fMRI mental imagery paradigms like imagining playing tennis can reveal covert awareness and enable binary communication in some unresponsive patients.

10.- Such fMRI paradigms are very challenging to implement clinically, making EEG-based brain-computer interfaces attractive for assessing awareness at the bedside.

11.- The Mindbeagle system is the first commercially available EEG-BCI for disorders of consciousness, developed through collaboration between Laureys' team and others.

12.- Pupillometry, EMG, respiration, and salivary pH have also been explored for enabling communication in unresponsive patients, but are impractical clinically.

13.- False negatives and false positives remain a challenge for BCIs in this population due to artifacts, brain damage, and other confounding factors.

14.- Cross-validation with other neuroimaging and EEG measures can increase confidence in BCI findings of covert awareness in unresponsive patients.

15.- Circadian rhythms and windows of higher arousal may impact the optimal timing and success of BCI assessments in these patients.

16.- Language impairments are common in MCS and can confound command-following and communication-based assessments of awareness.

17.- Functional connectivity within and between external and internal awareness networks appears critical for emergence of consciousness.

18.- The precuneus may be a critical hub in the posterior parietal cortex for awareness.

19.- Machine learning classifiers applied to brain connectivity patterns can help distinguish truly unresponsive from minimally conscious patients.

20.- Covert awareness as revealed by fMRI and EEG is a predictor of better long-term outcomes.

21.- Vagal nerve stimulation, tDCS, focused ultrasound, and other methods are being explored to facilitate recovery of consciousness.

22.- Zolpidem and apomorphine paradoxically increase behavioral responsiveness in some patients and may modulate mesocircuit dynamics to improve awareness.

23.- Ethical issues are critical when using BCIs and neuroimaging to assess awareness in patients unable to communicate.

24.- Pain perception appears intact in MCS based on brain responses and may warrant routine analgesic treatment even if patients cannot express pain.

25.- Surveys of locked-in syndrome patients reveal a majority have positive quality of life, predicted by access to assistive communication technology.

26.- Families of patients with disorders of consciousness prioritize receiving medical information, involvement in care decisions, and psychosocial support.

27.- Portrayals of quality of life in media do not match actual patient experiences and more translational research is needed.

28.- Risks and benefits must be weighed for invasive neuromodulatory interventions like deep brain stimulation that are still investigational.

29.- Non-invasive neuromodulation approaches like tDCS, vagal nerve stimulation and others show promise and will likely see more clinical use.

30.- Trajectory of recovery depends on age, etiology and other factors, but even chronic patients can sometimes show late improvements.

Knowledge Vault built byDavid Vivancos 2024