Neuroplasticity

Meditation practitioners had greater cortical thickness in the prefrontal cortex and right anterior insula compared to controls, with the prefrontal difference most pronounced in older participants, and thickness in two regions correlated with meditation experience.

observational cohort Sample size: 20

Serotonergic psychedelics robustly increased neuritogenesis and spinogenesis in the prefrontal cortex via TrkB, mTOR, and 5-HT2A signaling pathways.

laboratory study

Brain activation in sustained attention regions showed an inverted u-shaped curve with meditation expertise, and experts showed less activation in discursive thought regions and more in response inhibition regions during distracter sounds.

observational cohort

Psilocybin treatment decreased amygdala cerebral blood flow and increased default-mode network connectivity, with specific connectivity changes predicting clinical response at five weeks.

observational cohort Sample size: 19

Chronic pain was associated with decreased connectivity of medial prefrontal cortex to posterior default mode network regions and increased connectivity to insular cortex, with changes correlated to pain intensity and duration.

observational cohort

Intracellular 5-HT2ARs, not cell-surface ones, mediate the plasticity-promoting effects of psychedelics, explaining why serotonin does not engage similar plasticity mechanisms.

experimental study

Psychedelics directly bind to TrkB with high affinity to produce antidepressant-like effects independently of serotonin 2A receptor activation.

experimental study

Psilocybin's antidepressant action correlated with global increases in brain network integration, as indicated by decreased fMRI brain network modularity.

open-label trial and double-blind phase II randomized controlled trial

Mindfulness training reduced affective Stroop conflict and increased dorsolateral prefrontal cortex responses during executive processing, but only participants with the greatest amount of practice showed improvements in response inhibition and increased recruitment of anterior cingulate, medial prefrontal, and insular regions during negative valence processing.

randomized controlled trial

Psilocybin reduced negative affect and amygdala reactivity at one week, but negative affect and amygdala response returned to baseline at one month while positive affect remained elevated and resting-state functional connections increased.

open-label pilot study Sample size: 12

Ketamine rapidly induces synaptogenesis and spine formation in the prefrontal cortex via stimulation of the mammalian target of the rapamycin signaling pathway, reversing stress-induced atrophy and producing rapid antidepressant effects.

review

Psilocybin therapy increased cognitive flexibility for at least four weeks, but greater increases in neural flexibility between the ACC and PCC were associated with less improvement in cognitive flexibility.

open-label study Sample size: 24

LSD-induced increases in brain entropy predicted lasting increases in the personality trait openness two weeks later, especially during music listening and when ego dissolution was reported.

balanced-order, placebo-controlled study Sample size: 19

Psychedelics promote neuroplasticity through mechanisms including dendritogenesis, synaptogenesis, neurogenesis, and expression of plasticity-related genes, particularly in the prefrontal cortex and hippocampus.

review

LSD increased effective connectivity from the thalamus to the posterior cingulate cortex via serotonin 2A receptor activation and decreased connectivity from the ventral striatum to the thalamus independently of those receptors.

double-blind, randomized, placebo-controlled, cross-over study Sample size: 25

The BDNF/CREB signaling pathway serves as a core hub mediating multisystem network dysfunction in depression, integrating emotional-cognitive circuits, HPA axis activity, neurotransmitter systems, and neuroplasticity.

review

Classic psychedelics affect behavioral domains overlapping with ASD phenotypes through neurobiological mechanisms that converge with alterations implicated in ASD, but direct evidence from validated animal models of ASD is scarce.

review

Blocking CX3CL1/CX3CR1 signaling prevents ketamine's antidepressant-like behavioral effects and its enhancement of synaptic plasticity in mice.

animal study

Psilocybin transiently increases dendritic calcium event rates in apical tufts in a brain state- and 5-HT2A receptor-dependent manner, and alters the predictive relationship between acute dendritic calcium signaling and subsequent spine formation.

experimental study

Proposes a descriptive framework, Post-Perturbation Integrative Neuroplasticity, to characterize broad cross-domain cognitive reorganization following significant perturbation events, distinguishing it from pathological conditions and post-traumatic growth.

theoretical or philosophical paper

Ketamine and esketamine have the strongest evidence among rapid-acting antidepressant interventions for treatment-resistant depression, while psilocybin-assisted therapy shows promise but remains investigational.

review

Psilocybin's effect on synaptic density is modulated by environmental context, with a therapeutic-like setting associated with greater increases in synaptic density and more intense mystical-type experiences than an MRI scanner setting.

observational cohort Sample size: 15

Ketamine and MDMA induce peripheral DNA methylation changes that converge on neuroplasticity and neuroimmune pathways.

clinical trial Sample size: 36

Ketamine combined with psychotherapy shows promising reductions in craving and increases in abstinent days for alcohol and cocaine use disorders, but effects on relapse prevention are inconsistent and the drug carries a well-established risk of misuse.

narrative review

Proposes that Christian commitment and practice may yield dedicated neural structures or networks over time and foster interplay with secular cognition, and outlines hypotheses and methods to test this.

theoretical or philosophical paper