It’s not a surprise that societal crises like the COVID-19 pandemic can diminish mental health. Now, a new study led by researchers from the University of Southern California (USC) finds that US adults with higher levels of neuroticism—a personality trait characterized by worry, emotional sensitivity, and stronger reactions to stress—experienced greater and more persistent increases in mental distress during the pandemic than those with lower levels of that trait. 

The findings, published yesterday in PLOS One, help indicate how personality may indicate vulnerability to mental distress during a crisis. 

“There is a wide variety of mental health responses to large-scale societal stressors,” says lead author Marco Angrisani, PhD, a senior economist at the USC’s Center for Economic and Social Research, in a university news release. “Our study shows that personality traits, and neuroticism in particular, play a role in shaping heterogeneous responses in a major crisis across individuals and could therefore inform better targeted interventions.”

The researchers analyzed survey responses from 4,030 US adults who participated in the Understanding America Study. Data were collected from 2019 through February 2024, which allowed comparisons of mental health before, throughout, and after the pandemic. 

The researchers examined the ‘Big Five’ personality traits: neuroticism, extraversion (a tendency to be outgoing), openness (curiosity about new ideas and willingness to consider change), agreeableness (a tendency to be cooperative and trusting), and conscientiousness (a tendency to be organized and self-disciplined). 

Mental distress was assessed using the Patient Health Questionnaire, which measures depression and anxiety symptoms. Scores of six or higher indicate moderate to severe depression or anxiety. 

Our study shows that personality traits, and neuroticism in particular, play a role in shaping heterogeneous responses in a major crisis.

Compared with participants in the lowest quartile (one-fourth) for neuroticism, those in the highest quartile experienced increases in the probability of moderate or severe distress that were 11 to 20 percentage points higher during the pandemic. The link between neuroticism and increased distress persisted across all ages and continued after the emergency phase of the pandemic ended. 

Participants with higher neuroticism scores also perceived greater health and financial risks and reported engaging in more protective behaviors, like wearing masks and physical distancing. They also reported relaxing and exercising less and drinking alcohol more. The other personality traits showed weaker or inconsistent associations. 

“Our findings point to a highly asymmetric role of personality across the pandemic period,” write the researchers. “Neuroticism emerged as the primary and most robust correlate of sustained mental distress…[and] these differences remained statistically significant throughout subsequent phases and into the aftermath of the pandemic.”

The authors note that communicating during public health crises presents particular challenges for people with high levels of neuroticism, who may magnify perceived threats and uncertainties. 

They recommend that public health officials craft messages that balance awareness with reassurance and emphasize protective actions people can take, such as vaccination and physical distancing. Messages designed within this framework could encourage prevention without heightening anxiety. 

The findings may help clinicians identify who needs extra follow-up and support during public health emergencies. But, they continue, personality should be just one part of a broader risk assessment. Clinicians should consider previous mental illnesses, symptoms, and social circumstances.

“Neuroticism emerges as the principal personality-linked risk factor for sustained mental distress during the COVID-19 pandemic, a finding that is consistent across time, age groups, and measurement approaches,” conclude the researchers. “This highlights the relevance of personality traits for identifying individuals who may require sustained support, while cautioning against universal intervention based solely on personality profiles.”