Background Recent work suggests that psilocybin, a hallucinogenic 5-HT 2A R agonist with rapid and long-lasting anti-depressant actions, facilitates fear extinction retention in adult rodents. However, psilocybin’s effects on adolescent fear extinction are unknown. Further, chronic stress in adolescence predisposes individuals to developing psychopathologies such as anxiety and fear-related...
Background Deficits in prefrontal cortex (PFC) inhibitory transmission are thought to underlie the cognitive symptoms of schizophrenia that remain untreated by current pharmacotherapies. The metabotropic glutamate 1 (mGlu1) receptor, a subtype of the mGlu receptor family, is a promising therapeutic target because its activation enhances inhibitory transmission in the PFC through the excitation...
Schizophrenia research has traditionally viewed visual processing abnormalities as downstream consequences of cortical dysfunction. However, the epidemiological observation that congenital cortical blindness appears to confer protection against schizophrenia, while peripheral blindness, regardless of its developmental timing, does not, indicates that visual input itself may play a more...
BACKGROUND Depression is a prevalent and debilitating affective disorder characterised by the dominance and persistence of depressive rumination. Mindfulness-based cognitive therapy (MBCT) is an effective treatment for recurrent depression developed specifically to target rumination and recurrence risk by training metacognitive awareness and adaptive attention, emotion and self-regulation...
Background Cannabis use is associated with increased risk of psychotic disorders, but the underlying biological mechanisms remain unclear. We used genetic data to investigate the molecular pathways contributing to the association between cannabis use disorder (CUD) and psychosis. Methods We conducted a cross-disorder meta-analysis of genome-wide association studies (GWASs) on schizophrenia and...
Ketamine is increasingly used as a therapeutic option for treatment-resistant depression (TRD) due to its rapid antidepressant properties; however, the mechanisms underlying these effects remain elusive. Preclinical evidence suggests ketamine acts on neural pathways implicated in reward processing, but translational efforts have proven challenging due to a lack of paradigms allowing for...
Dissociation, an altered state of consciousness in which individuals feel detached from their body, environment, and sense of self, is a common feature of posttraumatic stress disorder (PTSD). Despite its significance, the neurocognitive processes underlying dissociation remain poorly understood, potentially limiting diagnostic precision and treatment efficacy in PTSD. To address this gap, we...
Psychedelics, particularly psilocin, are increasingly being studied for their mind-altering effects and potential therapeutic applications in psychiatry. Visual hallucinations, especially the illusion of motion in static images, are a hallmark of their action. Despite growing interest, the underlying mechanisms remain poorly understood, as their systematic evaluation in both humans and animals...
A significant share of meditation research relies on trait psychometric measures of mindfulness, which neglect the complex and dynamic unfolding of experiential processes entailed by meditation over time. However, there have been a few attempts to capture ongoing changes in experience during meditation. In this study, we integrated and expanded on 3 of these previous approaches to create a...
Dissociative states, characterized by discontinuities in awareness and perception, occur in a diverse array of psychiatric disorders and contexts. These states have been experimentally modeled in the laboratory through various induction methods, but relatively little is known about the efficacy and comparability of different experimental methods. In this meta-analysis, we quantified...
Internet gaming disorder (IGD) is a pervasive global mental health issue, and finding effective treatments for the disorder has been challenging. Mindfulness meditation (MM), recognized for its holistic approach that involves integrating mental and physical facets, holds promise for addressing the multifaceted nature of addiction. Nevertheless, the effect of MM on IGD and its associated neural...
Treatment-resistant depression (TRD) remains a challenge, but intravenous racemic ketamine offers rapid antidepressant effects. Reliable biomarkers are needed. In this study, we examined kynurenine pathway metabolites and inflammatory cytokines as predictors of ketamine response. The Bio-K study was a multicenter, open-label trial of 74 patients with TRD who received 3 ketamine infusions over...
Adolescent-onset cannabis use confers higher risk for neuropsychiatric disorders, implicating amygdala dysfunction. However, the mechanisms that mediate Δ9-tetrahydrocannabinol (THC)-triggered neuroadaptive changes in the maturing amygdala remain unclear. Proteomic analysis of amygdala tissue from male adolescent Saimiri boliviensis nonhuman primates chronically treated with THC provided leads...
Nitrous oxide ("laughing gas") is an NMDA receptor antagonist. In the current study, our aim was to investigate the efficacy, safety, and likely optimal dose of nitrous oxide in adults with major depressive disorder (MDD). In this phase 2b randomized, double-blind trial, 81 patients with MDD were allocated on a 1:1 basis to receive nitrous oxide or oxygen/air (control); the nitrous group was...
Dissociation is a widespread phenomenon with profound implications for mental health because dissociative experiences can become maladaptive, and these symptoms are prevalent, disruptive, and costly, both in direct health care expenses and indirect costs (1). Dissociation occurs across various diagnostic categories, and there is growing evidence that dissociation predicts poorer treatment...
A major theme of this SI is a focus on new experimental EEG studies of mindfulness, which fully leverage some of the key advantages and more recent advances in analytic approaches possible with this methodology. As described in the BP:CNNI review by Lin et al.
The Hallucinogen Rating Scale (HRS) has been widely used to measure the subjective effects of psychedelics and other psychoactive substances. Its advantages include a basis in phenomenological interviews and clinical studies, straightforward items, and broad coverage of psychedelic effects. Previous studies have attempted to resolve its factor structure but were limited by small samples of...
There has been rapid growth of neuroelectrophysiological studies that aspire to uncover the "black box" of mindfulness and meditation. Reliance on traditional data analysis methods hinders understanding of the complex, nonlinear, multidimensional, and systemic nature of the functional neuroelectrophysiology of meditation states. Thus, to reveal the complex systemic neuroelectrophysiology of...
In this study, we investigated whether mindfulness- and meditation-based mental training that improves stress regulation can upregulate BDNF (brain-derived neurotrophic factor), an important promoter of hippocampal neuroplasticity, and examined cortisol reduction as a mediating pathway. In a randomized clinical trial, 332 healthy adults were randomly assigned to one of the 3 training cohorts or...
Shorter telomeres are associated with increased risk of cognitive decline and age-related diseases. Developing interventions to promote healthy aging by preserving telomere integrity is of paramount importance. Here, we investigated the effect of an 18-month meditation intervention on telomere length (TL) measures in older people without cognitive impairment. A total of 137 adults age ≥65 years...
Interoceptive attention to internal sensory signals, such as the breath, is fundamental to mindfulness. However, interoceptive attention can be difficult to study, with many studies relying on subjective and retrospective measures. Response consistency is an established method for evaluating variability of attention on exteroceptive attention tasks, but it has rarely been applied to...
Trait mindfulness-the tendency to attend to present-moment experiences without judgment-is negatively correlated with adolescent anxiety and depression. Understanding the neural mechanisms that underlie trait mindfulness may inform the neural basis of psychiatric disorders. However, few studies have identified brain connectivity states that are correlated with trait mindfulness in adolescence,...
Short mindfulness-based interventions have gained traction in research due to their positive impact on well-being, cognition, and clinical symptoms across various settings. However, these short-term trainings are viewed as preliminary steps within a more extensive transformative path, presumably leading to long-lasting trait changes. Despite this, little is still known about the brain...
Meditation practices have demonstrated numerous psychological and physiological benefits, but capturing the neural correlates of varying meditative depths remains challenging. In this study, we aimed to decode self-reported time-varying meditative depth in expert practitioners using electroencephalography (EEG). Expert Vipassana meditators ( n = 34) participated in 2 separate sessions....
Ketamine, an NMDA receptor antagonist, provides rapid antidepressant effects. Although much research has focused on neural and molecular mechanisms of action, it is critical to also consider psychological mechanisms that may contribute to its therapeutic efficacy. The construct of an awe-inducing experience, which is a well-validated psychological phenomenon tied to emotional well-being, had...