A complex systems perspective on psychedelic brain action

Trends in Cognitive Sciences, Год журнала: 2023, Номер 27(5), С. 433 - 445

Опубликована: Фев. 3, 2023

Язык: Английский

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Large-scale neural dynamics in a shared low-dimensional state space reflect cognitive and attentional dynamics

eLife, Год журнала: 2023, Номер 12

Опубликована: Июль 3, 2023

Cognition and attention arise from the adaptive coordination of neural systems in response to external internal demands. The low-dimensional latent subspace that underlies large-scale dynamics relationships these cognitive attentional states, however, are unknown. We conducted functional magnetic resonance imaging as human participants performed tasks, watched comedy sitcom episodes an educational documentary, rested. Whole-brain traversed a common set states spanned canonical gradients brain organization, with global desynchronization among networks modulating state transitions. Neural were synchronized across people during engaging movie watching aligned narrative event structures. reflected fluctuations such different indicated engaged task naturalistic contexts, whereas lapses both contexts. Together, results demonstrate traversals along organization reflect dynamics.

Язык: Английский

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Neuromodulatory control of complex adaptive dynamics in the brain

Interface Focus, Год журнала: 2023, Номер 13(3)

Опубликована: Апрель 14, 2023

How is the massive dimensionality and complexity of microscopic constituents nervous system brought under sufficiently tight control so as to coordinate adaptive behaviour? A powerful means for striking this balance poise neurons close critical point a phase transition, at which small change in neuronal excitability can manifest nonlinear augmentation activity. brain could mediate transition key open question neuroscience. Here, I propose that different arms ascending arousal provide with diverse set heterogeneous parameters be used modulate receptivity target neurons-in other words, act mediating order. Through series worked examples, demonstrate how neuromodulatory interact inherent topological subsystems complex behaviour.

Язык: Английский

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Structural connections between the noradrenergic and cholinergic system shape the dynamics of functional brain networks

NeuroImage, Год журнала: 2022, Номер 260, С. 119455 - 119455

Опубликована: Июль 7, 2022

Complex cognitive abilities are thought to arise from the ability of brain adaptively reconfigure its internal network structure as a function task demands. Recent work has suggested that this inherent flexibility may in part be conferred by widespread projections ascending arousal systems. While different components system often studied isolation, there anatomical connections between neuromodulatory hubs we hypothesise crucial for mediating key features adaptive dynamics, such balance integration and segregation. To test hypothesis, estimated strength structural connectivity noradrenergic cholinergic systems (the locus coeruleus [LC] nucleus basalis Meynert [nbM], respectively). We then asked whether LC nbM inter-connectivity was related individual differences emergent, dynamical signatures functional measured resting state fMRI data, attractor topography. observed significant positive relationship white-matter extent network-level following BOLD signal peaks relative activity. In addition, individuals with denser streamlines interconnecting also demonstrated heightened shift novel states. These results suggest stronger have greater capacity mediate flexible dynamics required support complex, behaviour. Furthermore, our highlight underlying static can impose some constraints on dynamic brain.

Язык: Английский

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Neuronal connected burst cascades bridge macroscale adaptive signatures across arousal states

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Окт. 27, 2023

Abstract The human brain displays a rich repertoire of states that emerge from the microscopic interactions cortical and subcortical neurons. Difficulties inherent within large-scale simultaneous neuronal recording limit our ability to link biophysical processes at microscale emergent macroscopic states. Here we introduce network model layer-5 pyramidal neurons display graded coarse-sampled dynamics matching those observed in macroscale electrophysiological recordings macaques humans. We invert identify spike burst differentiate unconscious, dreaming, awake arousal provide insights into their functional signatures. further show neuromodulatory can mediate different modes around low-dimensional energy landscape, which turn changes response external stimuli. Our results highlight promise multiscale modelling bridge theories consciousness across spatiotemporal scales.

Язык: Английский

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The biological role of local and global fMRI BOLD signal variability in human brain organization

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Окт. 23, 2023

Variability drives the organization and behavior of complex systems, including human brain. Understanding variability brain signals is thus necessary to broaden our window into function behavior. Few empirical investigations macroscale signal have yet been undertaken, given difficulty in separating biological sources variance from artefactual noise. Here, we characterize temporal most predominant signal, fMRI BOLD systematically investigate its statistical, topographical neurobiological properties. We contrast acquisition protocols, integrate across histology, microstructure, transcriptomics, neurotransmitter receptor metabolic data, static connectivity, simulated magnetoencephalography data. show that represents a spatially heterogeneous, central property multi-scale multi-modal organization, distinct Our work establishes relevance provides lens on stochasticity spatial scales.

Язык: Английский

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Causal evidence for cholinergic stabilization of attractor landscape dynamics

Cell Reports, Год журнала: 2024, Номер 43(6), С. 114359 - 114359

Опубликована: Июнь 1, 2024

There is substantial evidence that neuromodulatory systems critically influence brain state dynamics; however, most work has been purely descriptive. Here, we quantify, using data combining local inactivation of the basal forebrain with simultaneous measurement resting-state fMRI activity in macaque, causal role long-range cholinergic input to stabilization states cerebral cortex. Local nucleus basalis Meynert (nbM) leads a decrease energy barriers required for an transition cortical ongoing activity. Moreover, particular nbM sub-regions predominantly affects information transfer regions known receive direct anatomical projections. We demonstrate these results simple neurodynamical model impact on neuronal firing rates and slow hyperpolarizing adaptation currents. conclude system plays critical stabilizing macroscale dynamics.

Язык: Английский

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Exploring the Suitability of Piecewise-Linear Dynamical System Models for Cognitive Neural Dynamics

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2025, Номер unknown

Опубликована: Янв. 15, 2025

Abstract Dynamical system models have proven useful for decoding the current brain state from neural activity. So far, neuroscience has largely relied on either linear or nonlinear based artificial networks. Piecewise approximations of dynamics in other technical applications, providing a clear advantage over network-based models, when dynamical is not only supposed to be observed, but also controlled. Here we explore whether piecewise-linear (recurrent Switching Linear System rSLDS models) could modeling dynamics, particular context cognitive tasks. We first generate data computational model perceptual decision-making and demonstrate that can successfully recovered these observations. then outperforms terms predicting future states associated Finally, apply our approach publicly available dataset recorded monkeys performing decisions. Much surprise, did provide significant data, although were estimated different trial epochs showed qualitatively dynamics. In summary, present prove situations, where needs controlled closed-loop fashion, example, new neuromodulation applications treating deficits. Future work will show under what conditions are sufficiently warrant use one.

Язык: Английский

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The road to Aha: A recipe for mental breakthroughs

Cognition, Год журнала: 2025, Номер 257, С. 106081 - 106081

Опубликована: Фев. 11, 2025

Язык: Английский

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Gain neuromodulation mediates task-relevant perceptual switches: evidence from pupillometry, fMRI, and RNN Modelling

Опубликована: Фев. 27, 2025

Perceptual updating has been hypothesized to rely on a network reset modulated by bursts of ascending neuromodulatory neurotransmitters, such as noradrenaline, abruptly altering the brain’s susceptibility changing sensory activity. To test this hypothesis at large-scale, we analysed an ambiguous figures task using pupillometry and functional magnetic resonance imaging (fMRI). Behaviourally, qualitative shifts in perceptual interpretation image were associated with peaks pupil diameter, indirect readout phasic tone. We further that stimulus ambiguity drives tone leading heightened neural gain, hastening switches. explore computationally, trained recurrent (RNN) analogous categorisation task, allowing gain change dynamically classification uncertainty. As predicted, higher accelerated switching transiently destabilizing network’s dynamical regime periods maximal leveraged low-dimensional RNN dynamics, develop two novel macroscale predictions: switches should occur brain state velocity flattened egocentric energy landscape. Using fMRI confirmed these predictions, highlighting role system large-scale reconfigurations mediating adaptive updates.

Язык: Английский

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