HighlightsAdolescent abstinent cannabis users showed significantly greater activation in the dorsolateral and ventrolateral prefrontal and posterior parietal cortices compared to controls.Adolescent users showed increased activation in regions involved in executive functioning, attentional control and the default mode network compared to non‐using controls.No significant group differences in...
In this meta-analysis, we aimed to assess the evidence from neuroimaging studies for chronic alterations in the brains of MDMA users. The databases PubMed, Embase, and Web of Science were searched for studies published from inception to August 24, 2018, without any language restriction. Sixteen independent studies comprising 356 MDMA users and 311 controls were included. Of these, five studies...
Previous studies have reported conflicting results in terms of acute effects of cannabis in man. Independently of other factors, such discrepancy may be attributable to the different cannabis use history of study volunteers. It is thought that regular cannabis users may develop tolerance to the effects of acute cannabis administration. Here we systematically review all studies examining the...
HIGHLIGHTSInternalizing disorders characterized by aberrant self‐referential processing and emotion dysregulation.Mindfulness training modulates self‐referential processing and reduces internalizing symptoms.Change in self‐referential processing may be key mechanism underlying therapeutic effects of mindfulness training. ABSTRACT The aim of the current review is to advance the hypothesis that...
Growing evidence has suggested that mindfulness-based interventions (MBIs) could have beneficial effects on the acute phase of depression and on the prevention of depressive relapse or recurrence. Despite growing clinical interest, the effects of MBIs on brain functioning in patients with MDD remain unclear. The aim of this systematic review was to assess the changes in brain functioning...
Serotonergic psychedelics act as agonists at cortical 5-HT2A receptors and seem to induce personality changes. We conducted a systematic review of studies assessing the effects of these drugs on personality. Papers published from 1985-2016 were included from PubMed, LILACS, and SciELO databases. Three hundred and sixty-nine studies were identified, and 18 were included. Specific personality...
Extensive debates continue regarding marijuana (Cannabis spp), the most commonly used illicit substance in many countries worldwide. There has been an exponential increase of cannabis studies over the past two decades but the drug's long-term effects still lack in-depth scientific data. The epigenome is a critical molecular machinery with the capacity to maintain persistent alterations of gene...
Humans often face binary cognitive-control dilemmas, with the choice between persistence and flexibility being a crucial one. Tackling these dilemmas requires metacontrol, i.e., the control of the current cognitive-control policy. As predicted from functional, psychometric, neuroscientific, and modeling approaches, interindividual variability in metacontrol biases towards persistence or...
Time and space are the basic building blocks of nature. As a unique existent in nature, our brain exists in time and takes up space. The brain's activity itself also constitutes and spreads in its own (intrinsic) time and space that is crucial for consciousness. Consciousness is a complex phenomenon including different dimensions: level/state, content/form, phenomenal aspects, and cognitive...
MDMA/Ecstasy has had a resurgence in popularity, with recent supplies comprising higher strength MDMA, potentially leading to increased drug-related harm. Neurocognitive problems have been widely reported in ecstasy users, equally some studies report null findings, and it remains unclear which factors underlie the development of neurocognitive impairments. This review covers the empirical...
Cannabis use represents a major public health issue throughout the globe. Yet, we still lack the most fundamental knowledge on long-term effects of cannabis on neural, cognitive, and behavioral function. Part of this stems from how cannabis has been measured historically. To this end, most empirical examinations of cannabis have consolidated all types of cannabis collectively. However, this...
Growing clinical and pre-clinical evidence points to a critical role for cannabidiol (CBD), the largest phytochemical component of cannabis, as a potential pharmacotherapy for various neuropsychiatric disorders. In contrast to delta-9-tetrahydrocannabinol (THC), which is associated with acute and neurodevelopmental pro-psychotic side-effects, CBD possesses no known psychoactive or...
Hypnosis is a unique form of top-down regulation in which verbal suggestions are capable of eliciting pronounced changes in a multitude of psychological phenomena. Hypnotic suggestion has been widely used both as a technique for studying basic science questions regarding human consciousness but also as a method for targeting a range of symptoms within a therapeutic context. Here we provide a...
A broad range of mind-body therapies (MBTs) are used by the public today, and a growing body of clinical and basic sciences research has resulted in evidence-based integration of many MBTs into clinical practice. Basic sciences research has identified some of the physiological correlates of MBT practices, leading to a better understanding of the processes by which emotional, cognitive and...
We present the theory of predictive processing as a unifying framework to account for the neurocognitive basis of religion and spirituality. Our model is substantiated by discussing four different brain mechanisms that play a key role in religion and spirituality: temporal brain areas are associated with religious visions and ecstatic experiences; multisensory brain areas and the default mode...
Serotonergic hallucinogens produce alterations of perceptions, mood, and cognition, and have anxiolytic, antidepressant, and antiaddictive properties. These drugs act as agonists of frontocortical 5-HT2A receptors, but the neural basis of their effects are not well understood. Thus, we conducted a systematic review of neuroimaging studies analyzing the effects of serotonergic hallucinogens in...
We conducted a meta-analysis on the available data from studies investigating SERTs in ecstasy users and polydrug using controls. From 7 studies we compared data from 157 ecstasy users and 148 controls across 14 brain regions. The main effect suggested ecstasy/MDMA related SERT reductions (SMD=0.52, 95% CIs [0.40, 0.65]; Z=8.36, p<.01, I(2)=89%). A significant effect of subgroups (X(2)=37.41,...
Meditation is a family of mental practices that encompasses a wide array of techniques employing distinctive mental strategies. We systematically reviewed 78 functional neuroimaging (fMRI and PET) studies of meditation, and used activation likelihood estimation to meta-analyze 257 peak foci from 31 experiments involving 527 participants. We found reliably dissociable patterns of brain...
MDMA ("ecstasy") is widely used as a recreational drug, although there has been some debate about its neurotoxic effects in humans. However, most studies have investigated subjects with heavy use patterns, and the effects of transient MDMA use are unclear. In this review, we therefore focus on subjects with moderate use patterns, in order to assess the evidence for harmful effects. We searched...
The full body of research on the nature of psychosis and its determinants indicates that a considerable number of factors are relevant to the development of hallucinations, delusions, and other positive symptoms, ranging from neurodevelopmental parameters and altered connectivity of brain regions to impaired cognitive functioning and social factors. We aimed to integrate these factors in a...
Users of ±3,4-Methylenedioxymethamphetamine (MDMA; ‘ecstasy’) report prosocial effects such as sociability and empathy. Supporting these apparently unique social effects, data from controlled laboratory studies indicate that MDMA alters social feelings, information processing, and behavior in humans, and social behavior in rodents. Here, we review this growing body of evidence. In rodents, MDMA...
A variety of anatomical and physiological evidence suggests that the brain performs computations using motifs that are repeated across species, brain areas, and modalities. The computational architecture of cortex, for example, is very similar from one area to another and the types, arrangements, and connections of cortical neurons are highly stereotyped. This supports the idea that each...
Mindfulness meditation has been purported as a beneficial practice for wellbeing. It would be expected that the neurophysiology of mindfulness would reflect this impact on wellbeing. However, investigations of the effect of mindfulness have generated mixed reports of increases, decreases, as well as no differences in EEG oscillations in comparison with a resting state and a variety of tasks. We...
The role of cannabis in the etiology of schizophrenia has been documented as possibly the strongest environmental risk factor. However, the pathomechanism whereby cannabis use increases this risk has not yet been identified. We argue that this pathomechanism may involve direct effects of exogenous cannabinoids on T-type calcium channels in the thalamus. These channels are crucial for...
Solving the problem of consciousness remains one of the biggest challenges in modern science. One key step towards understanding consciousness is to empirically narrow down neural processes associated with the subjective experience of a particular content. To unravel these neural correlates of consciousness (NCC) a common scientific strategy is to compare perceptual conditions in which...