3,4-Methylenedioxymethamphetamine as a Psychiatric Treatment.
Bedi, G. (2018). 3, 4-methylenedioxymethamphetamine as a psychiatric treatment. JAMA psychiatry, 75(5), 419-420., https://doi.org/10.1001/jamapsychiatry.2018.0063
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G. Bedi
The Prosocial Effects of 3,4-methylenedioxymethamphetamine (MDMA): Controlled Studies in Humans and Laboratory Animals
Abstract
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 increases passive prosocial behavior (adjacent lying) and social reward while decreasing aggression, effects that may involve serotonin 1A receptor mediated oxytocin release interacting with vasopressin receptor 1A. In humans, MDMA increases plasma oxytocin and produces feelings of social affiliation. It decreases identification of negative facial expressions (cognitive empathy) and blunts responses to social rejection, while enhancing responses to others’ positive emotions (emotional empathy) and increasing social approach. Thus, consistent with drug folklore, laboratory administration of MDMA robustly alters social processing in humans and increases social approach in humans and animals. Effects are consistent with increased sociability, with mixed evidence about enhanced empathy. These neurobiologically-complex prosocial effects likely motivate recreational ecstasy use.
Kamilar-Britt, P., & Bedi, G. (2015). The Prosocial Effects of 3, 4-methylenedioxymethamphetamine (MDMA): Controlled Studies in Humans and Laboratory Animals. Neuroscience & Biobehavioral Reviews. http://dx.doi.org/10.1016/j.neubiorev.2015.08.016
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Intimate insight: MDMA changes how people talk about significant others
Abstract
Rationale: ±3,4-methylenedioxymethamphetamine (MDMA) is widely believed to increase sociability. The drug alters speech production and fluency, and may influence speech content. Here, we investigated the effect of MDMA on speech content, which may reveal how this drug affects social interactions.
Method: Thirty-five healthy volunteers with prior MDMA experience completed this two-session, within-subjects, double-blind study during which they received 1.5 mg/kg oral MDMA and placebo. Participants completed a five-minute standardized talking task during which they discussed a close personal relationship (e.g. a friend or family member) with a research assistant. The conversations were analyzed for selected content categories (e.g. words pertaining to affect, social interaction, and cognition), using both a standard dictionary method (Pennebaker’s Linguistic Inquiry and Word Count: LIWC) and a machine learning method using random forest classifiers.
Results: Both analytic methods revealed that MDMA altered speech content relative to placebo. Using LIWC scores, the drug increased use of social and sexual words, consistent with reports that MDMA increases willingness to disclose. Using the machine learning algorithm, we found that MDMA increased use of social words and words relating to both positive and negative emotions.
Conclusions: These findings are consistent with reports that MDMA acutely alters speech content, specifically increasing emotional and social content during a brief semistructured dyadic interaction. Studying effects of psychoactive drugs on speech content may offer new insights into drug effects on mental states, and on emotional and psychosocial interaction.
Baggott, M. J., Kirkpatrick, M. G., Bedi, G., & de Wit, H. (2015). Intimate insight: MDMA changes how people talk about significant others. Journal of Psychopharmacology, 0269881115581962. https://dx.doi.org/
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A window into the intoxicated mind? Speech as an index of psychoactive drug effects.
Abstract
Abused drugs can profoundly alter mental states in ways that may motivate drug use. These effects are usually assessed with self-report, an approach that is vulnerable to biases. Analyzing speech during intoxication may present a more direct, objective measure, offering a unique ‘window’ into the mind. Here, we employed computational analyses of speech semantic and topological structure after ±3,4-methylenedioxymethamphetamine (MDMA; ‘ecstasy’) and methamphetamine in 13 ecstasy users. In 4 sessions, participants completed a 10-min speech task after MDMA (0.75 and 1.5 mg/kg), methamphetamine (20 mg), or placebo. Latent Semantic Analyses identified the semantic proximity between speech content and concepts relevant to drug effects. Graph-based analyses identified topological speech characteristics. Group-level drug effects on semantic distances and topology were assessed. Machine-learning analyses (with leave-one-out cross-validation) assessed whether speech characteristics could predict drug condition in the individual subject. Speech after MDMA (1.5 mg/kg) had greater semantic proximity than placebo to the concepts friend, support, intimacy, and rapport. Speech on MDMA (0.75 mg/kg) had greater proximity to empathy than placebo. Conversely, speech on methamphetamine was further from compassion than placebo. Classifiers discriminated between MDMA (1.5 mg/kg) and placebo with 88% accuracy, and MDMA (1.5 mg/kg) and methamphetamine with 84% accuracy. For the two MDMA doses, the classifier performed at chance. These data suggest that automated semantic speech analyses can capture subtle alterations in mental state, accurately discriminating between drugs. The findings also illustrate the potential for automated speech-based approaches to characterize clinically relevant alterations to mental state, including those occurring in psychiatric illness.
Bedi, G., Cecchi, G. A., Slezak, D. F., Carrillo, F., Sigman, M., & de Wit, H. (2014). A window into the intoxicated mind? speech as an index of psychoactive drug effects. Neuropsychopharmacology. https://dx.doi.org/10.1038/npp.2014.80