Serotonergic psychedelic drugs LSD and psilocybin reduce the hierarchical differentiation of unimodal and transmodal cortex

@article{Girn2022SerotonergicPD,
  title={Serotonergic psychedelic drugs LSD and psilocybin reduce the hierarchical differentiation of unimodal and transmodal cortex},
  author={Manesh Girn and Leor Roseman and Boris C. Bernhardt and Jonathan Smallwood and Robin Lester Carhart-Harris and R. Nathan Spreng},
  journal={NeuroImage},
  year={2022},
  volume={256}
}

The effect of lysergic acid diethylamide (LSD) on whole-brain functional and effective connectivity

Investigating the neural mechanisms of lysergic acid diethylamide (LSD) using regression dynamic causal modelling (rDCM), a novel technique that assesses whole-brain effective connectivity (EC) during resting-state functional magnetic resonance imaging (fMRI), suggests that LSD perturbs the Excitation/Inhibition balance of the brain.

LSD and psilocybin flatten the brain’s energy landscape: insights from receptor-informed network control theory

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Receptor-informed network control theory links LSD and psilocybin to a flattening of the brain’s control energy landscape

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LSD flattens the brain’s energy landscape: evidence from receptor-informed network control theory

The findings provide support for a fundamental of the mechanism of action of LSD by showing that LSD flattens the energy allowing for more facile and frequent state transitions and more temporally diverse also demonstrate that the spatial distribution of serotonin 2a receptors - the main target of LSD is key for generating these effects.

Does Psychedelic Therapy Have a Transdiagnostic Action and Prophylactic Potential?

It is proposed that a model of psychedelic-induced plasticity combined with an adequate therapeutic context has prophylactic and transdiagnostic potential, implying that it could have a broad, positive impact on public health.

Ritualistic use of ayahuasca enhances a shared functional connectome identity with others

These findings offer an example as to how individualised connectivity markers can be used to trace a subject’s functional connectome across altered states of consciousness and show that interindividual differences in higher-order FCs motifs are relevant to experiential phenotypes.

Prefrontal contributions to the stability and variability of thought and conscious experience

This work brings two recently introduced theoretical frameworks—the dynamic framework of thought (DFT) and the relaxed beliefs under psychedelics (REBUS) model) together to provide a synthesis of how prefrontal subregions may differentially contribute to the stability and variability of thought and conscious experience.

Cortical gradients during naturalistic processing are hierarchical and modality-specific

This work identifies principal movie gradients that delineate separate hierarchies anchored in sensorimotor, visual, and auditory/language areas that provide an ecologically valid representation of the principles underlying cortical organization while the brain is active and engaged in multimodal, dynamic perceptual and cognitive processing.

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