Globally elevated excitation–inhibition ratio in children with autism spectrum disorder and below-average intelligence DOI Creative Commons
Viktoriya O. Manyukhina, Andrey O. Prokofyev, Ilia A. Galuta

et al.

Molecular Autism, Journal Year: 2022, Volume and Issue: 13(1)

Published: May 12, 2022

Abstract Background Altered neuronal excitation–inhibition (E–I) balance is strongly implicated in ASD. However, it not known whether the direction and degree of changes E–I ratio individuals with ASD correlates intellectual disability often associated this developmental disorder. The spectral slope aperiodic 1/f activity reflects at scale large populations may uncover its putative alternations without disability. Methods Herein, we used magnetoencephalography (MEG) to test would differentiate children average below–average (< 85) IQ. MEG was recorded rest eyes open/closed 49 boys aged 6–15 years IQ ranging from 54 128, age-matched typically developing (TD) boys. cortical source estimated using beamformer approach individual brain models. We then extracted by fitting a linear function log–log-scale power spectra high-frequency range. Results global averaged over all sources demonstrated high rank-order stability between two conditions. Consistent previous research, steeper eyes-closed than eyes-open condition flattened age. Regardless condition, below-average had flatter slopes either TD or above-average These group differences could be explained signal-to-noise periodic (alpha beta) activity. Limitations Further research needed find out observed ratios are characteristic other diagnostic groups. Conclusions atypically suggests shift toward hyper-excitation. can provide an accessible noninvasive biomarker for making objective judgments about treatment effectiveness people comorbid

Language: Английский

Consciousness is supported by near-critical slow cortical electrodynamics DOI Creative Commons
Daniel Toker, Ioannis Pappas, Janna D. Lendner

et al.

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(7)

Published: Feb. 10, 2022

Significance What changes in the brain when we lose consciousness? One possibility is that loss of consciousness corresponds to a transition brain’s electric activity away from edge-of-chaos criticality, or knife’s edge between stability and chaos. Recent mathematical developments have produced tools for testing this hypothesis, which apply cortical recordings diverse states. We show cortex indeed poised near boundary chaos during conscious states transitions unconsciousness disrupts information processing.

Language: Английский

Citations

103
Quantifying arousal and awareness in altered states of consciousness using interpretable deep learning DOI Creative Commons
Minji Lee, Leandro Sanz, Alice Barra

et al.

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Feb. 25, 2022

Consciousness can be defined by two components: arousal (wakefulness) and awareness (subjective experience). However, neurophysiological consciousness metrics able to disentangle between these components have not been reported. Here, we propose an explainable indicator (ECI) using deep learning the of consciousness. We employ electroencephalographic (EEG) responses transcranial magnetic stimulation under various conditions, including sleep (n = 6), general anesthesia 16), severe brain injury 34). also test our framework resting-state EEG 15) ECI simultaneously quantifies physiological, pharmacological, pathological conditions. Particularly, ketamine-induced rapid eye movement with low high are clearly distinguished from other states. In addition, parietal regions appear most relevant for quantifying awareness. This provides insights into neural correlates altered states

Language: Английский

Citations

86
Distributed harmonic patterns of structure-function dependence orchestrate human consciousness DOI Creative Commons
Andrea I. Luppi, Jakub Vohryzek, Morten L. Kringelbach

et al.

Communications Biology, Journal Year: 2023, Volume and Issue: 6(1)

Published: Jan. 28, 2023

Abstract A central question in neuroscience is how consciousness arises from the dynamic interplay of brain structure and function. Here we decompose functional MRI signals pathological pharmacologically-induced perturbations into distributed patterns structure-function dependence across scales: harmonic modes human structural connectome. We show that coupling a generalisable indicator under bi-directional neuromodulatory control. find increased scales during loss consciousness, whether due to anaesthesia or injury, capable discriminating between behaviourally indistinguishable sub-categories brain-injured patients, tracking presence covert consciousness. The opposite signature characterises altered state induced by LSD ketamine, reflecting psychedelic-induced decoupling function correlating with physiological subjective scores. Overall, connectome decomposition reveals neuromodulation network architecture jointly shape activation scales.

Language: Английский

Citations

69
The aperiodic exponent of subthalamic field potentials reflects excitation/inhibition balance in Parkinsonism DOI Creative Commons
Christoph Wiest, Flavie Torrecillos, Alek Pogosyan

et al.

eLife, Journal Year: 2023, Volume and Issue: 12

Published: Feb. 22, 2023

Periodic features of neural time-series data, such as local field potentials (LFPs), are often quantified using power spectra. While the aperiodic exponent spectra is typically disregarded, it nevertheless modulated in a physiologically relevant manner and was recently hypothesised to reflect excitation/inhibition (E/I) balance neuronal populations. Here, we used cross-species vivo electrophysiological approach test E/I hypothesis context experimental idiopathic Parkinsonism. We demonstrate dopamine-depleted rats that exponents at 30–100 Hz subthalamic nucleus (STN) LFPs defined changes basal ganglia network activity; higher tally with lower levels STN neuron firing tipped towards inhibition. Using STN-LFPs recorded from awake Parkinson’s patients, show accompany dopaminergic medication deep brain stimulation (DBS) STN, consistent untreated manifesting reduced inhibition hyperactivity STN. These results suggest Parkinsonism reflects might be candidate biomarker for adaptive DBS.

Language: Английский

Citations

49
A neurophysiological basis for aperiodic EEG and the background spectral trend DOI Creative Commons
Niklas Brake,

Flavie Duc,

Alexander Rokos

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Feb. 19, 2024

Abstract Electroencephalograms (EEGs) display a mixture of rhythmic and broadband fluctuations, the latter manifesting as an apparent 1/f spectral trend. While network oscillations are known to generate EEG, neural basis EEG remains unexplained. Here, we use biophysical modelling show that aperiodic activity can detectable scalp potentials shape features, but these signals do not significantly perturb brain rhythm quantification. Further model analysis demonstrated profoundly corrupted by shifts in synapse properties. To examine this scenario, recorded EEGs human subjects being administered propofol, general anesthetic GABA receptor agonist. Drug administration caused changes quantitatively matched propofol’s effects on receptors. We used our correct for confounding changes, which revealed delta power, uniquely, increased within seconds individuals losing consciousness. Altogether, work details how shaped neurophysiological factors other than rhythms elucidates undermine traditional interpretation.

Language: Английский

Citations

31
Aperiodic EEG and 7T MRSI evidence for maturation of E/I balance supporting the development of working memory through adolescence DOI Creative Commons
Shane D. McKeon,

Maria I. Perica,

Ashley C. Parr

et al.

Developmental Cognitive Neuroscience, Journal Year: 2024, Volume and Issue: 66, P. 101373 - 101373

Published: April 1, 2024

Adolescence has been hypothesized to be a critical period for the development of human association cortex and higher-order cognition. A defining feature is shift in excitation: inhibition (E/I) balance neural circuitry, however how changes E/I may enhance cortical circuit function support maturational improvements cognitive capacities not known. Harnessing ultra-high field 7 T MR spectroscopy EEG large, longitudinal cohort youth (N = 164, ages 10–32 years old, 347 neuroimaging sessions), we delineate biologically specific associations between age-related excitatory glutamate inhibitory GABA neurotransmitters EEG-derived measures aperiodic activity reflective prefrontal cortex. Specifically, find that developmental increases reflected glutamate:GABA are linked assessed by suppression activity, which turn facilitates robust working memory. These findings indicate role E/I-engendered signaling mechanisms maturation maintenance. More broadly, this multi-modal imaging study provides evidence undergoes physiological consistent with plasticity during adolescence.

Language: Английский

Citations

23
Spectral Slope and Lempel–Ziv Complexity as Robust Markers of Brain States during Sleep and Wakefulness DOI Creative Commons
Christopher Höhn, Michael A Hahn, Janna D. Lendner

et al.

eNeuro, Journal Year: 2024, Volume and Issue: 11(3), P. ENEURO.0259 - 23.2024

Published: March 1, 2024

Nonoscillatory measures of brain activity such as the spectral slope and Lempel–Ziv complexity are affected by many neurological disorders modulated sleep. A multitude frequency ranges, particularly a broadband (encompassing full spectrum) narrowband approach, have been used especially for estimating slope. However, effects choosing different ranges not yet explored in detail. Here, we evaluated impact sleep stage task engagement (resting, attention, memory) on (30–45 Hz) (1–45 range 28 healthy male human subjects (21.54 ± 1.90 years) using within-subject design over 2 weeks with three recording nights days per subject. We strived to determine how states affect two perform comparison. In range, steepened, decreased continuously from wakefulness N3 REM sleep, however, was best discriminated Importantly, also differed between tasks during wakefulness. While engagement, flattened both ranges. Interestingly, only positively correlated performance. Our results show that sensitive indices state variations yields more information could be greater variety research questions than complexity, when is used.

Language: Английский

Citations

22
Memantine Effects on Electroencephalographic Measures of Putative Excitatory/Inhibitory Balance in Schizophrenia DOI
Juan L. Molina, Bradley Voytek, Michael L. Thomas

et al.

Biological Psychiatry Cognitive Neuroscience and Neuroimaging, Journal Year: 2020, Volume and Issue: 5(6), P. 562 - 568

Published: Feb. 22, 2020

Language: Английский

Citations

131
Are intrinsic neural timescales related to sensory processing? Evidence from abnormal behavioral states DOI Creative Commons
Federico Zilio, Javier Gómez‐Pilar, Shumei Cao

et al.

NeuroImage, Journal Year: 2020, Volume and Issue: 226, P. 117579 - 117579

Published: Nov. 20, 2020

The brain exhibits a complex temporal structure which translates into hierarchy of distinct neural timescales. An open question is how these intrinsic timescales are related to sensory or motor information processing and whether dynamics have common patterns in different behavioral states. We address questions by investigating the brain's healthy controls, (amyotrophic lateral sclerosis, locked-in syndrome), (anesthesia, unresponsive wakefulness progressive reduction (from awake states over N1, N2, N3). employed combination measures from EEG resting-state data: auto-correlation window (ACW), power spectral density (PSD), power-law exponent (PLE). Prolonged accompanied shift towards slower frequencies were observed conditions with deficits, but not deficits. Our results establish that spontaneous activity's timescale capacity specifically supports rather than brain.

Language: Английский

Citations

90
General Anesthesia: A Probe to Explore Consciousness DOI Creative Commons
Vincent Bonhomme, Cécile Staquet, Javier Montupil

et al.

Frontiers in Systems Neuroscience, Journal Year: 2019, Volume and Issue: 13

Published: Aug. 14, 2019

General anesthesia reversibly alters consciousness, without shutting down the brain globally. Depending on anesthetic agent and dose, it may produce different consciousness states including a complete absence of subjective experience (unconsciousness), conscious perception environment (disconnected like during dreaming), or episodes oriented with awareness (connected consciousness). Each state potentially be followed by explicit implicit memories after procedure. In this respect, can considered as proxy to explore consciousness. During recent years, progress in exploration function has allowed better understanding neural correlates their alterations anesthesia. Several changes functional effective between-region connectivity, network topology, spatio-temporal dynamics interactions have been evidenced Despite set effects that are common many agents, is still uneasy draw comprehensive picture precise cascades general questions remain unsolved, exact identification substrate its components, detection specific unresponsive patients associated memory processes, processing sensory information anesthesia, pharmacodynamic between direction-dependent hysteresis phenomenon transitions states, mechanisms cognitive follow an procedure, eventual unitary mechanism anesthesia-induced alteration relationship biochemical sleep-wake cycle targets well vast between-studies variations dose administration mode, leading difficulties comparisons. narrative review, we current knowledge unconsciousness, from insights gathered propofol, halogenated vapors, ketamine, dexmedetomidine, benzodiazepines xenon. We also describe how help develop above-mentioned unresolved questions, propose tracks for future research.

Language: Английский

Citations

85