Mental health over the life course: Evidence for a U-shape?
Hermien Dijk & Jochen Mierau
Health Economics, forthcoming
Mental health problems impose substantial individual and societal costs over the life-cycle. The age-profile of mental health problems is, however, not well understood. Hence, we study the age-profile of mental health while introducing minimal bias to reach identification. Using mental health data from the United States Panel Study of Income Dynamics we apply first difference estimation to derive an unbiased estimate of the second derivative of the age effect as well as an estimate up to a linear period trend of the first derivative. Next, we use a battery of estimators with varying restrictions to approximate the first derivative. Our results suggest that the age profile of mental health in the US is not U-shaped and we find tentative evidence that the age-profile could follow an inverse U-shape where individuals experience a mental health high during their life course. Further analyses, using German and Dutch data, confirm that these results do not only apply to the US, but also to Germany and the Netherlands.
Social Media and Teenage Mental Health: Quasi-Experimental Evidence
University of Toronto Working Paper, November 2022
Teenage mental health has been a source of growing concern over the past decade, with recent whistleblower testimony pointing to the mental health risks of spending time on social media platforms, especially for girls. This paper investigates the extent to which social media are harmful for teenagers, leveraging rich administrative data from the Canadian province of British Columbia and quasi-experimental variation related to the introduction of wireless internet there. I show neighbourhoods covered by high- speed wireless internet have significantly higher social media use, based on Google search volume data. In the main analysis, I link spatial data on broadband coverage to 20 years of student records that provide detailed information about individual student health. Using this novel data linkage, I estimate a triple-difference model comparing teen girls to teen boys in terms of school-reported mental health diagnoses, before and after visual social media emerged, and across neighbourhoods with and without access to high-speed wireless internet. Estimates indicate high-speed wireless internet significantly increased teen girls' severe mental health diagnoses -- by 90% -- relative to teen boys over the period when visual social media became dominant in teenage internet use. I find similar effects across all subgroups. When applying the same strategy, I find null impacts for placebo health conditions -- ones through which there is no clear channel for social media to operate. The evidence points to adverse effects of visual social media, in light of large gender gaps in visual social media use and documented risks. In turn, the analysis calls attention to policy interventions that could mitigate the harm to young people due to their online activities.
Depressive Symptoms and Conspiracy Beliefs
Jon Green et al.
Applied Cognitive Psychology, forthcoming
Conspiratorial beliefs can endanger individuals and societies by increasing the likelihood of harmful behaviors such as the flouting of public health guidelines. While scholars have identified various correlates of conspiracy beliefs, one factor that has received scant attention is depressive symptoms. We use three large surveys to explore the connection between depression and conspiracy beliefs. We find a consistent association, with the extent of the relationship depending on individual and situational factors. Interestingly, those from relatively advantaged demographic groups (i.e., White, male, high income, educated) exhibit a stronger relationship between depression and conspiracy beliefs than those not from such groups. Further, situational variables that ostensibly increase stress-such as having COVID-19 or parenting during COVID-19-exacerbate the relationship while those that seem to decrease stress, such as social support, vitiate it. The results provide insight about the development of targeted interventions and accentuate the need for theorizing about the mechanisms that lead depression to correlate with conspiracy beliefs.
Bullying and conspiracy theories: Experiences of workplace bullying and the tendency to engage in conspiracy theorizing
Daniel Jolley & Anthony Lantian
Social Psychology, Fall 2022, Pages 198-208
Experiences of bullying in the workplace can increase anxiety, paranoia, and hypervigilance to threat in victims. Such factors are also associated with conspiracy beliefs. Two preregistered studies (cross-sectional and experimental) tested whether bullying experiences may be linked to the development of conspiracy beliefs. Study 1 (n = 273) demonstrated that experiences of workplace bullying were positively associated with conspiracy beliefs, an effect that could be explained by paranoia. In Study 2 (n = 206), participants who imagined being bullied (vs. supported) reported increased belief in conspiracy theories. Our research uncovers another antecedent of conspiracy beliefs: workplace bullying. Future research should endeavor to explore how best to support victims and avert the link between being bullied and conspiracy theorizing emerging.
Behavioural and dopaminergic signatures of resilience
Lindsay Willmore et al.
Nature, 3 November 2022, Pages 124-132
Chronic stress can have lasting adverse consequences in some individuals, yet others are resilient to the same stressor. Susceptible and resilient individuals exhibit differences in the intrinsic properties of mesolimbic dopamine (DA) neurons after the stressful experience is over. However, the causal links between DA, behaviour during stress and individual differences in resilience are unknown. Here we recorded behaviour in mice simultaneously with DA neuron activity in projections to the nucleus accumbens (NAc) (which signals reward) and the tail striatum (TS) (which signals threat) during social defeat. Supervised and unsupervised behavioural quantification revealed that during stress, resilient and susceptible mice use different behavioural strategies and have distinct activity patterns in DA terminals in the NAc (but not the TS). Neurally, resilient mice have greater activity near the aggressor, including at the onset of fighting back. Conversely, susceptible mice have greater activity at the offset of attacks and onset of fleeing. We also performed optogenetic stimulation of NAc-projecting DA neurons in open loop (randomly timed) during defeat or timed to specific behaviours using real-time behavioural classification. Both open-loop and fighting-back-timed activation promoted resilience and reorganized behaviour during defeat towards resilience-associated patterns. Together, these data provide a link between DA neural activity, resilience and resilience-associated behaviour during the experience of stress.
Nostalgia restores meaning in life for lonely people
Andrew Abeyta & Jacob Juhl
Lonely individuals lack meaning in life. We hypothesized that nostalgia, a bittersweet emotion that entails reflecting sentimentally on the past, helps restore meaning for lonely people. In two studies, we measured trait loneliness, measured state nostalgia (Study 1) or experimentally induced nostalgia (Study 2), and assessed meaning. Results supported the hypothesis: The relation between loneliness and meaning deficits was reduced among nostalgic individuals and this was driven by the fact that nostalgia (whether measured or experimentally induced) was linked with greater meaning for highly lonely individuals.
Do humans prefer cognitive effort over doing nothing?
Raymond Wu, Amanda Ferguson & Michael Inzlicht
Journal of Experimental Psychology: General, forthcoming
Humans and other animals find mental (and physical) effort aversive and have the fundamental drive to avoid it. However, doing nothing is also aversive. Here, we ask whether people choose to avoid effort when the alternative is to do nothing at all. Across 12 studies, participants completed variants of the demand selection task, in which they repeatedly selected between a cognitively effortful task (e.g., simple addition, Stroop task, and symbol-counting task) and a task that required no effort (e.g., doing nothing, watching the computer complete the Stroop, and symbol-viewing). We then tabulated people's choices. Across our studies and an internal meta-analysis, we found little evidence that people choose to avoid effort (and hints that people sometimes prefer effort) when the alternative was doing nothing. Our findings suggest that doing nothing can be just as costly - if not more costly - than exerting effort.