MDMA as well as amphetamine and alcohol increase feelings of social closeness in healthy adults.

Psychoactive drugs such as alcohol and stimulants are typically used in social settings such as bars, parties or small groups. Yet, relatively little is known about how social contexts affect responses to drugs, or how the drugs alter social interactions. It is possible that positive social contexts enhance the rewarding properties of drugs, perhaps increasing their potential for repeated use and abuse.

Alcohol increases social engagement in dyadic interactions: role of partner's drug state.

Rationale: Alcohol is commonly used in social environments and is known to facilitate social behaviors. However, most controlled laboratory studies on alcohol have been conducted in isolated settings, limiting our understanding of its effects on social interactions.

Objectives: The current study was designed to examine the effects of alcohol on dyadic interactions in healthy volunteers (N = 37), with a focus on the influence of the conversation partner's drug state.

Social Homeostasis and Psychoactive Drugs: What Can We Learn From Opioid and Amphetamine Drug Challenge Studies in Humans?

Social disequilibrium, or disrupted social homeostasis, underlies many behavioral disorders, including problematic drug use. One way to study the relationship between drug use and social homeostasis is to determine whether single doses of psychoactive drugs relieve some of the discomfort of social isolation and promote social connection. In this narrative review, we discuss challenges and opportunities in studying the relationship between psychoactive drugs and social homeostasis.

Impact of childhood adversity on acute subjective effects of stimulant and opioid drugs: Evidence from placebo-controlled studies in healthy volunteers.

Background And Aims: Early-life adversities are known to alter drug reward processing in rodents. Despite the well-known link between early adversity and the risk of substance use disorder, few studies have measured how childhood adversity affects human drug reward. Here, we assessed the relationship between historical childhood adversities and responses to single doses of methamphetamine, d-amphetamine or buprenorphine in healthy participants.

Methamphetamine-induced adaptation of learning rate dynamics depend on baseline performance.

The ability to calibrate learning according to new information is a fundamental component of an organism's ability to adapt to changing conditions. Yet, the exact neural mechanisms guiding dynamic learning rate adjustments remain unclear. Catecholamines appear to play a critical role in adjusting the degree to which we use new information over time, but individuals vary widely in the manner in which they adjust to changes.

The 3,4-methylenedioxymethamphetamine enhances early visual processing for salient socio-emotional stimuli.

The 3,4-methylenedioxymethamphetamine (MDMA) has long been used non-medically, and it is currently under investigation for its potential therapeutic benefits. Both uses may be related to its ability to enhance empathy, sociability, emotional processing and its anxiolytic effects. However, the neural mechanisms underlying these effects, and their specificity to MDMA compared to other stimulants, are not yet fully understood.

Neural complexity is increased after low doses of LSD, but not moderate to high doses of oral THC or methamphetamine.

Neural complexity correlates with one's level of consciousness. During coma, anesthesia, and sleep, complexity is reduced. During altered states, including after lysergic acid diethylamide (LSD), complexity is increased.

Microdosing Psychedelics: Current Evidence From Controlled Studies.

Taking regular low doses of psychedelic drugs (microdosing) is a practice that has drawn recent scientific and media attention for its potential psychotherapeutic effects. Yet, controlled studies evaluating this practice have lagged. Here, we review recent evidence focusing on studies that were conducted with rigorous experimental control.

MDMA enhances positive affective responses to social feedback.

Background: The prosocial compound ± 3,4-methylenedioxymethamphetamine (MDMA) is an amphetamine derivative that has shown promise as an adjunct to psychotherapy in the treatment of post-traumatic stress disorder. MDMA increases positive responses to social images, and it has been suggested that the ability of MDMA to positively bias social perception may underlie its therapeutic efficacy as a psychotherapy adjunct. However, the effect of the compound on affective responses to positive or negative social feedback has not been tested.

Lack of effect of methamphetamine on reward-related brain activity in healthy adults.

Introduction: Stimulant drugs are thought to alter processing of rewarding stimuli. However, the mechanisms by which they do this are not fully understood.

Method: In this study we used EEG to assess effects of single doses of methamphetamine (MA) on neural responses during anticipation and receipt of reward in healthy volunteers.

Unique effects of sedatives, dissociatives, psychedelics, stimulants, and cannabinoids on episodic memory: A review and reanalysis of acute drug effects on recollection, familiarity, and metamemory.

Despite distinct classes of psychoactive drugs producing putatively unique states of consciousness, there is surprising overlap in terms of their effects on episodic memory and cognition more generally. Episodic memory is supported by multiple subprocesses that have been mostly overlooked in psychopharmacology and could differentiate drug classes. Here, we reanalyzed episodic memory confidence ratings from 10 previously published data sets (28 drug conditions total) using signal detection models to estimate two conscious states involved in episodic memory and one consciously controlled metacognitive process of memory: autonoetic retrieval of specific details (recollection), noetic recognition absent of retrieved details (familiarity), and retrospective introspection of memory decisions (metamemory).

Greater subjective effects of a low dose of LSD in participants with depressed mood.

Recent studies and anecdotal reports suggest that psychedelics can improve mood states, even at low doses. However, few placebo-controlled studies have examined the acute effects of low doses of LSD in individuals with psychiatric symptoms. In the current study, we examined the acute and sub-acute effect of a low dose of LSD (26 µg) on subjective effects and mood in volunteers with mild depressed mood.

Drug-induced social connection: both MDMA and methamphetamine increase feelings of connectedness during controlled dyadic conversations.

MDMA is a stimulant-like drug with distinctive empathogenic effects. Its pro-social effects, such as feelings of connectedness, may contribute to both its popularity as a recreational drug and its apparent value as an adjunct to psychotherapy. However, little is known about the behavioral processes by which MDMA affects social interactions.

Methamphetamine enhances neural activation during anticipation of loss in the monetary incentive delay task.

Stimulants like methamphetamine (MA) affect motivated behaviors via actions on circuits mediating mood, attention, and reward. Few studies examined the effects of single doses of stimulants on reward circuits during anticipation and receipt of rewards and losses. Here, we examined the effects of MA (20 mg) or placebo in a within-subject, double-blind study with healthy adults ( = 43).

Methamphetamine alters nucleus accumbens neural activation to monetary loss in healthy young adults.

Rationale: Stimulant drugs like methamphetamine (MA) activate brain reward circuitry, which is linked to the development of problematic drug use. It is not clear how drugs like MA alter neural response to a non-drug reward.

Objectives: We examined how acute MA impacts neural response to receipt of a monetary reward relative to a loss in healthy adults.

Social Psychopharmacology: Novel Approaches to Treat Deficits in Social Motivation in Schizophrenia.

Background And Hypothesis: Diminished social motivation is a negative symptom of schizophrenia and leads to severe functional consequences for many patients suffering from the illness. However, there are no effective medications available to treat this symptom. Despite the lack of approved treatments for patients, there is a growing body of literature on the effects of several classes of drugs on social motivation in healthy volunteers that may be relevant to patients.

Stimulant-like subjective effects of alcohol are not related to resting-state connectivity in healthy men.

Individual differences in subjective, stimulant-like effects of alcohol are associated with the risk of developing alcohol use disorder. Specifically, individuals who experience more pronounced stimulant-like effects from alcohol are more likely to continue and escalate their usage. The neural basis for these individual differences in subjective response is not yet known.

The acute effects of psychoactive drugs on emotional episodic memory encoding, consolidation, and retrieval: A comprehensive review.

Psychoactive drugs modulate learning and emotional processes in ways that could impact their recreational and medical use. Recent work has revealed how drugs impact different stages of processing emotional episodic memories, specifically encoding (forming memories), consolidation (stabilizing memories), and retrieval (accessing memories). Drugs administered before encoding may preferentially impair (e.

Impaired inhibition after delta-9-tetrahydrocannabinol in women not related to circulating estradiol levels.

Cannabis and its main psychoactive constituent, delta-9-tetrahydrocannabinol (THC), impair cognitive processes, including the ability to inhibit inappropriate responses. However, responses to cannabinoid drugs vary widely, and little is known about the factors that influence the risk for adverse effects. One potential source of variation in response to cannabinoids in women is circulating ovarian hormones such as estradiol and progesterone.

Place conditioning in humans: opportunities for translational research.

Rationale: Translational research, especially research that bridges studies with humans and nonhuman species, is critical to advancing our understanding of human disorders such as addiction. This advancement requires reliable and rigorous models to study the underlying constructs contributing to the maladaptive behavior.

Objective: In this commentary, we address some of the challenges of conducting translational research by examining a single procedure, place conditioning.

Low doses of lysergic acid diethylamide (LSD) increase reward-related brain activity.

Renewed interest in classic psychedelics as treatments for psychiatric disorders warrants a deeper understanding of their neural mechanisms. Single, high doses of psychedelic drugs have shown promise in treating depressive disorders, perhaps by reversing deficits in reward processing in the brain. In addition, there are anecdotal reports that repeated ingestion of low doses of LSD, or "microdosing", improve mood, cognition, and feelings of wellbeing.