Mental Space
Being present: Witnessing landmark historical events boosts meaning in life
Yige Yin et al.
Journal of Personality and Social Psychology, forthcoming
Abstract:
Although not everyone shapes history, everyone is present as it unfolds. Recognizing oneself as a witness to history may become especially important in an era marked by frequent landmark events. In this research, we locate individuals in the ongoing process of history and examine its existential benefits. Specifically, we hypothesize that witnessing history (i.e., the subjective sense of witnessing or being present as history unfolds) enhances meaning in life, both in terms of the presence of meaning and the search for meaning. Through five investigations, using a multimethod approach that includes large-scale field data from Weibo (2,317,527 posts) alongside experimental and field studies (N = 1,945), we found that witnessing history contributes to or increases the presence of and search for meaning. Further, connectedness to history mediates the effect of witnessing history on the presence of meaning and a broadened perspective mediates its effect on the search for meaning. Our research provides a novel insight into how situating individuals within the ongoing process of history can benefit their meaningful existence and highlights the importance of cultivating a historical awareness and preserving historical heritage.
Broadband Internet Access and Adolescent Mental Health in the U.S.
Brandyn Churchill & Kathryn Johnson
NBER Working Paper, January 2026
Abstract:
Broadband internet has become a critical component of U.S. infrastructure, but policymakers are increasingly concerned that the widespread adoption of this technology has adversely affected adolescent mental health. To test this hypothesis, we use 2009-2019 National and State Youth Risk Behavior Survey data and leverage the nationwide rollout of broadband internet. First, we show that adolescents in states with greater broadband internet access reported spending more time online. Next, we find that a one-standard-deviation increase in broadband internet access was associated with a 9.3-16.5-percent increase in adolescent suicide ideation. While we document increases in suicide ideation for both girls and boys, the results are most pronounced for adolescent girls. Exploring potential mechanisms, we show that greater broadband internet access was associated with increases in cyberbullying and body dissatisfaction among adolescent girls and a reduction in the likelihood that adolescent boys reported getting an adequate amount of sleep.
AI for Proactive Mental Health: A Multi-Institutional, Longitudinal, Randomized Controlled Trial
Julie Cachia et al.
Harvard Working Paper, November 2025
Abstract:
Young adults today face unprecedented mental health challenges, yet many hesitate to seek support due to barriers such as accessibility, stigma, and time constraints. Bite-sized well-being interventions offer a promising solution to preventing mental distress before it escalates to clinical levels, but have not yet been delivered through personalized, interactive, and scalable technology. We conducted the first multi-institutional, longitudinal, preregistered randomized controlled trial of a generative AI-powered mobile app ("Flourish") designed to address this gap. Over six weeks in Fall 2024, 486 undergraduate students from three U.S. institutions were randomized to receive app access or waitlist control. Participants in the treatment condition reported significantly greater positive affect, resilience, and social well-being (i.e., increased belonging, closeness to community, and reduced loneliness) and were buffered against declines in mindfulness and flourishing. These findings suggest that, with purposeful and ethical design, generative AI can deliver proactive, population-level well-being interventions that produce measurable benefits.
Mimicking opioid analgesia in cortical pain circuits
Corinna Oswell et al.
Nature, forthcoming
Abstract:
The anterior cingulate cortex is a key brain region involved in the affective and motivational dimensions of pain, but how opioid analgesics modulate this cortical circuit remains unclear. Uncovering how opioids alter nociceptive neural dynamics to produce pain relief is essential for developing safer and more targeted treatments for chronic pain. Here we show that a population of cingulate neurons encodes spontaneous pain-related behaviours and is selectively modulated by morphine. Using deep learning behavioural analyses combined with longitudinal neural recordings in mice, we identified a persistent shift in cortical activity patterns following nerve injury that reflects the emergence of an unpleasant, affective chronic pain state. Morphine reversed these neuropathic neural dynamics and reduced affective-motivational behaviours without altering sensory detection or reflexive responses, mirroring how opioids alleviate pain unpleasantness in humans. Leveraging these findings, we built a biologically inspired chemogenetic gene therapy that targets opioid-sensitive neurons in the cingulate using a synthetic μ-opioid receptor promoter to drive inhibition. This opioid-mimetic chemogenetic gene therapy recapitulated the analgesic effects of morphine during chronic neuropathic pain, thereby offering a new strategy for precision pain management that targets a key nociceptive cortical opioid circuit with safe, on-demand analgesia.
The Soothing Effect of a Stable World: Social Behavior of Individuals Varying on Social Anxiety Under Fixed and Growth Mindsets About Impression Formation
Liad Uziel
Personality and Social Psychology Bulletin, forthcoming
Abstract:
Social anxiety (SA) entails perceiving interactions as threatening and is linked to detrimental social outcomes. This study tested whether individuals scoring higher on SA navigate interactions better when believing the impressions people form of others are relatively fixed (fixed mindset), thereby making interactions feel more controlled and less demanding. A Preliminary Study established that holding a fixed mindset attenuates how demanding interactions feel among individuals higher on SA. Three experiments manipulated impression formation mindsets. In Study 1, higher SA was associated with making a negative impression in a self-presentation task following a growth mindset induction (belief that impressions are malleable) but not following a fixed mindset induction. This pattern was repeated in Study 2 involving a stress-inducing self-presentation task. In Study 3, following a fixed mindset induction, SA predicted better real-life social experiences. In conclusion, a fixed model of impression formation may improve social functioning among individuals predisposed to SA.