Pharmacological, neural, and psychological mechanisms underlying psychedelics: A critical review.

This paper provides a critical review of several possible mechanisms at different levels of analysis underlying the effects and therapeutic potential of psychedelics. At the (1) biochemical level, psychedelics primarily affect the 5-HT2A receptor, increase neuroplasticity, offer a critical period for social reward learning, and have anti-inflammatory properties. At the (2) neural level, psychedelics have been associated with reduced efficacy of thalamo-cortical filtering, the loosening of top-down predictive signaling and an increased sensitivity to bottom-up prediction errors, and activation of the claustro-cortical-circuit. At the (3) psychological level, psychedelics have been shown to induce altered and affective states, they affect cognition, induce belief change, exert social effects, and can result in lasting changes in behavior. We outline the potential for a unifying account of the mechanisms underlying psychedelics and contrast this with a model of pluralistic causation. Ultimately, a better understanding of the specific mechanisms underlying the effects of psychedelics could allow for a more targeted therapeutic approach. We highlight current challenges for psychedelic research and provide a research agenda to foster insight in the causal-mechanistic pathways underlying the efficacy of psychedelic research and therapy.

The Light vs. Dark Triad of Personality: Contrasting Two Very Different Profiles of Human Nature.

While there is a growing literature on "dark traits" (i.e., socially aversive traits), there has been a lack of integration with the burgeoning research literature on positive traits and fulfilling and growth-oriented outcomes in life. To help move the field toward greater integration, we contrasted the nomological network of the Dark Triad (a well-studied cluster of socially aversive traits) with the nomological network of the Light Triad, measured by the 12-item Light Triad Scale (LTS). The LTS is a first draft measure of a loving and beneficent orientation toward others ("everyday saints") that consists of three facets: Kantianism (treating people as ends unto themselves), Humanism (valuing the dignity and worth of each individual), and Faith in Humanity (believing in the fundamental goodness of humans). Across four demographically diverse samples (N = 1,518), the LTS demonstrated excellent reliability and validity, predicting life satisfaction and a wide range of growth-oriented and self-transcendent outcomes above and beyond existing measures of personality. In contrast, the Dark Triad was negatively associated with life satisfaction and growth-oriented outcomes, and showed stronger linkages to selfish, exploitative, aggressive, and socially aversive outcomes. This exploratory study of the contrasting nomological networks of the Light vs. Dark Triad provides several ways forward for more principled and data driven approaches to explore both the malevolent and beneficent sides of human nature.

Moral attitudes and willingness to enhance and repair cognition with brain stimulation.

BACKGROUND: The availability of technological means to enhance and repair human cognitive function raises questions about the perceived morality of their use. However, we have limited knowledge about the public's intuitive attitudes toward uses of brain stimulation. Studies that enlighten us about the public's willingness to endorse specific uses of brain stimulation on themselves and others could provide a basis to understand the moral psychology guiding intuitions about neuromodulation and opportunities to inform public education and public policy. OBJECTIVE: Hypothesis: We expected that subjects would be less willing to enhance or repair cognitive functions perceived as more "core" to "authentic" self-identity, prioritize brain stimulation uses for themselves, and more willing to enhance "core" functions in others. Across specific hypothetical uses, we expected the moral acceptability of specific uses to be associated with subjects' willingness to endorse them. METHODS: We administered two surveys to the public in which subjects were asked to report how willing they would be to enhance or repair specific cognitive abilities using a hypothetical brain stimulation device called "Ceremode". RESULTS: Among 894 subjects, we found that subjects were more willing to use technologies to repair other people than themselves. They were most inclined to repair core functions in others. Subjects' ratings of the moral acceptability of specific uses was related to their reported willingness to use brain stimulation. CONCLUSION: Moral acceptability is related to the public's willingness to use brain stimulation. These findings suggest that the public endorses a generous approach to applying brain stimulation for cognitive gains in others. Further, this study establishes a basis to guide moral psychological studies of cognitive modification and social processes that guide attitudes toward and uses of brain stimulation.

Women are Warmer but No Less Assertive than Men: Gender and Language on Facebook.

Using a large social media dataset and open-vocabulary methods from computational linguistics, we explored differences in language use across gender, affiliation, and assertiveness. In Study 1, we analyzed topics (groups of semantically similar words) across 10 million messages from over 52,000 Facebook users. Most language differed little across gender. However, topics most associated with self-identified female participants included friends, family, and social life, whereas topics most associated with self-identified male participants included swearing, anger, discussion of objects instead of people, and the use of argumentative language. In Study 2, we plotted male- and female-linked language topics along two interpersonal dimensions prevalent in gender research: affiliation and assertiveness. In a sample of over 15,000 Facebook users, we found substantial gender differences in the use of affiliative language and slight differences in assertive language. Language used more by self-identified females was interpersonally warmer, more compassionate, polite, and-contrary to previous findings-slightly more assertive in their language use, whereas language used more by self-identified males was colder, more hostile, and impersonal. Computational linguistic analysis combined with methods to automatically label topics offer means for testing psychological theories unobtrusively at large scale.