A new brain metric called ISD, which combines measures of global connectivity and local clustering, can more accurately tell whether someone is conscious or unconscious than any single measure of brain connectivity alone.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether ISD consistently outperforms other fMRI-based biomarkers across diverse populations, anesthetics, and clinical settings for detecting consciousness.
A systematic review and meta-analysis of all published studies comparing ISD to other fMRI metrics (e.g., modularity, entropy, connectivity strength) for detecting consciousness in anesthesia, sleep, and disorders of consciousness, pooling AUC values from at least 30 independent cohorts with standardized preprocessing.
Whether using ISD to guide anesthesia depth reduces postoperative delirium or improves recovery outcomes compared to standard monitoring.
A multicenter double-blind RCT of 800 surgical patients randomized to receive anesthesia titrated by real-time ISD feedback vs. standard clinical monitoring (BIS), with primary outcome being incidence of postoperative delirium within 72 hours.
Whether ISD measured during wakefulness predicts vulnerability to anesthesia-induced unconsciousness or delayed recovery.
A prospective cohort study of 300 healthy adults undergoing elective surgery, measuring baseline ISD via fMRI and tracking time to loss and return of responsiveness during propofol induction and emergence, adjusting for age, BMI, and genetic factors.
Whether ISD reliably differentiates between minimally conscious and vegetative states in patients with brain injury.
A cross-sectional fMRI study comparing ISD in 50 patients with disorders of consciousness (25 minimally conscious, 25 vegetative) and 50 healthy controls, using identical scanning protocols and ISD calculation methods, with behavioral state confirmed by CRS-R scale.
Whether ISD changes in real time during emergence from anesthesia correlate precisely with moment-to-moment recovery of responsiveness.
A case series of 15 patients undergoing continuous fMRI during propofol emergence, with behavioral responsiveness assessed every 30 seconds via automated squeeze-response detection, synchronized to ISD fluctuations at 10-second resolution.