Emotions, Context, and Substance Use in Adolescents: A Large Language Model Analysis of Reddit Posts

By Jianfeng Zhu, Hailong Jiang, Yulan Wang, Karin G. Coifman, Ruoming Jin, Deric R. Kenne

DOI https://doi.org/10.48550/arXiv.2501.14037

Abstract

Early substance use during adolescence increases the risk of later substance usedisorders and mental health problems, yet the emotional and contextual factorsdriving these behaviors remain poorly understood. This study analyzed 23000substance-use related posts and an equal number of non-substance posts fromReddit’s r/teenagers community (2018-2022). Posts were annotated for sixdiscrete emotions (sadness, anger, joy, guilt, fear, disgust) and contextualfactors (family, peers, school) using large language models (LLMs). Statisticalanalyses compared group differences, and interpretable machine learning (SHAP)identified key predictors of substance-use discussions. LLM-assisted thematiccoding further revealed latent psychosocial themes linking emotions withcontexts. Negative emotions, especially sadness, guilt, fear, and disgust, weresignificantly more common in substance-use posts, while joy dominatednon-substance discussions. Guilt and shame diverged in function: guilt oftenreflected regret and self-reflection, whereas shame reinforced risky behaviorsthrough peer performance. Peer influence emerged as the strongest contextualfactor, closely tied to sadness, fear, and guilt. Family and school environmentsacted as both risk and protective factors depending on relational quality andstress levels. Overall, adolescent substance-use discussions reflected a dynamicinterplay of emotion, social context, and coping behavior. By integratingstatistical analysis, interpretable models, and LLM-based thematic exploration,this study demonstrates the value of mixed computational approaches foruncovering the emotional and contextual mechanisms underlying adolescent riskbehavior.

Summary of “Emotions, Context, and Substance Use in Adolescents: A Large Language Model Analysis of Reddit Posts”

Abstract

The study examines the factors that influence substance use among adolescents, highlighting the importance of real-time emotional and contextual influences. Through an analysis of 23,000 substance use posts on Reddit, along with a matched sample of non-substance use posts, researchers employed large language models to annotate emotions and contextual factors. They discovered that negative emotions such as sadness, guilt, fear, and disgust were prevalent in substance use posts, while joy was common in non-substance discussions. Peer influence emerged as the strongest contextual factor, and the findings suggest that addressing emotions and social contexts will be vital in substance use prevention strategies.

Introduction

Adolescent substance use poses significant health risks, with increasing numbers of teenagers reporting illicit drug use, particularly during the critical developmental phase of adolescence. Factors such as peer pressure, family dynamics, and school performance heavily influence these behaviors, but understanding the real-time interplay between emotions and these contexts is limited. Traditional methods such as surveys are insufficient for capturing the rapid emotional fluctuations and social dynamics adolescents experience daily. This study utilizes social media, particularly Reddit, to capture real-time youth emotions and interactions. Using advanced artificial intelligence and language models, the study aims to clarify how emotions and social contexts intertwine in discussions about substance use.

Research Aims

• Analyze the types of emotions present in substance-use posts compared to non-substance-use posts.
• Investigate how family, peer, and school contexts appear in these discussions.
• Understand the interrelation between emotions and context.
• Evaluate predictors of substance use discussions using machine learning.
• Use language models to extract themes linking emotions with contexts.

Methodology

The study involved analyzing user-generated posts from Reddit’s r/teenagers from 2018 to 2022. Posts related to various substances were identified through specific keywords. Each post was annotated for emotions (e.g., guilt, fear, joy) and contextual influences (e.g., family, peers, school) using a large language model. Statistical tests were conducted to compare substance use and non-substance use posts, followed by machine learning models to identify key predictors for substance-related discussions.

Findings

Emotional and Contextual Analysis

1. Emotional Distribution:
   • Negative Emotions: Sadness, guilt, fear, and disgust were significantly more present in substance use posts, indicating the emotional struggles adolescents face related to substance use.
   • Positive Emotion: Joy was significantly higher in non-substance use posts, pointing to healthier emotional states among those not engaging in substance use.
2. Contextual Factors:
   • Peer Influence: This was the most significant context associated with substance use discussions, strongly linked with feelings of sadness, fear, and guilt. Many adolescents felt pressured by peers, leading to risky behavior.
   • Family and School: Family dynamics showed both risk (e.g., parental conflict) and protective factors (a supportive home environment). School environments also influenced emotional states but had complex roles in either exacerbating or alleviating pressure related to substance use.
3. Predictive Modeling:
   • The study used a machine learning model to predict substance use discussions with an accuracy of about 67%. High levels of guilt and peer influence emerged as key indicators of these discussions.

Thematic Analysis

• Peer Contexts: Discussions often reflected themes of fear of exclusion, pressure to conform, and shame, illustrating how social dynamics significantly shape adolescent choices regarding substances.
• Family Dynamics: Posts indicated fear of parental discovery, guilt over disappointing family members, and sadness tied to problematic home environments, showcasing the dual nature of family as a risk and support system.
• School Environments: Anger and fear about peers and institutional responses to substance use emerged, indicating an emotionally charged school atmosphere influencing substance use behaviors.

Conclusion

This research underscores the complex interplay of emotions and social contexts in adolescent substance use. Key findings highlight peer pressure as a dominant influence and differentiate the emotional roles of guilt and shame. The study suggests that interventions need to consider these emotional and contextual factors at multiple levels (individual, familial, and social) to effectively address adolescent substance use.

Implications

The findings point to the necessity for comprehensive prevention programs that address peer dynamics, family influences, and school environments. Future research should leverage advanced analytical techniques to further understand these relationships across diverse populations.

Limitations

The study faced limitations, including reliance on publicly available data from Reddit, which may not fully represent the experiences of all adolescents. Further research is needed to validate findings across different platforms and demographic groups.