ArticleCognitive neurodynamics2018
Measures of entropy and complexity in altered states of consciousness.
Article in Cognitive neurodynamics, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 56 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
56 citing papers in PubMed, 1 synthesis or guideline pooled it.
- The Caffeinated Brain Part 3: The Effect of Caffeine on Electroencephalography (EEG) During Wakefulness-A Systematic and Mechanistic Review.Nutrients · 2026Pooled it
- Behavioral and electrophysiological effects of network-based frontoparietal tDCS in patients with severe brain injury: A randomized controlled trial.NeuroImage. Clinical · 2020Trial
- The entropic brain today.Brain : a journal of neurology · 2026Review
- Review
- Cognitive Processing and EEG Complexity.Entropy (Basel, Switzerland) · 2026Review
- Adversarial AI reveals mechanisms and treatments for disorders of consciousness.Nature neuroscience · 2026Article
- Task-specific dynamical entropy variations in EEG as a biomarker for Parkinson's disease progression.GeroScience · 2026Article
- EEG Brain Rhythms During Resting-State Wakefulness and Sleep in Elderly Expert Meditators.Journal of sleep research · 2026Article
- EEG correlates of sleep stages, sleep discrepancy, and insomnia: a comparative analysis of people with insomnia and healthy sleepers using spectral power and sample entropy.Frontiers in sleep · 2026Article
- The role of etiology in the identification of clinical markers of consciousness: comparing EEG alpha power, complexity, and spectral exponent.Cerebral cortex (New York, N.Y. : 1991) · 2025Article
- Detection of EEG dynamic complex patterns in disorders of consciousness.Communications biology · 2025Article
- Brain complexity represents uncertainty in sequence learning and corroborates habituation deficit in Parkinson disease patients.Scientific reports · 2025Article
- A Permutation Entropy Method for Sleep Disorder Screening.Brain sciences · 2025Article
- Both k-core percolation and directed graph analysis revealed succession and transition of voxels' spatiotemporal progress on dynamic correlation resting-state fMRI.Frontiers in human neuroscience · 2025Article
- Neural field modeling and analysis of consciousness states in the brain.Neuroscience of consciousness · 2025Article
- Consciousness and Energy Processing in Neural Systems.Brain sciences · 2024Article
- Critical dynamics in spontaneous EEG predict anesthetic-induced loss of consciousness and perturbational complexity.Communications biology · 2024Article
- Neural markers of reduced arousal and consciousness in mild cognitive impairment.International journal of geriatric psychiatry · 2024Article
- Spectral Slope and Lempel-Ziv Complexity as Robust Markers of Brain States during Sleep and Wakefulness.eNeuro · 2024Article
- The Constrained Disorder Principle May Account for Consciousness.Brain sciences · 2024Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Quantification of complexity in neurophysiological signals has been studied using different methods, especially those from information or dynamical system theory. These studies have revealed a dependence on different states of consciousness, and in particular that wakefulness is characterized by a greater complexity of brain signals, perhaps due to the necessity for the brain to handle varied sensorimotor information. Thus, these frameworks are very useful in attempts to quantify cognitive states. We set out to analyze different types of signals obtained from scalp electroencephalography (EEG), intracranial EEG and magnetoencephalography recording in subjects during different states of consciousness: resting wakefulness, different sleep stages and epileptic seizures. The signals were analyzed using a statistical (permutation entropy) and a deterministic (permutation Lempel-Ziv complexity) analytical method. The results are presented in complexity versus entropy graphs, showing that the values of entropy and complexity of the signals tend to be greatest when the subjects are in fully alert states, falling in states with loss of awareness or consciousness. These findings were robust for all three types of recordings. We propose that the investigation of the structure of cognition using the frameworks of complexity will reveal mechanistic aspects of brain dynamics associated not only with altered states of consciousness but also with normal and pathological conditions.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.