Until recently, many psychologists believed that personality traits such as extraversion or neuroticism were stable characteristics that hardly changed during adulthood. New research challenges this view, showing that personality is more plastic than assumed: it reacts to daily circumstances, stress, and social interactions and can shift even from day to day.
New research: personality as a “state,” not just a “trait”
A research team led by Fabian Gander (University of Basel and colleagues) developed and validated a tool — the FFM-PSI (Five-Factor Model Personality States Inventory), which makes it possible to measure personality states at specific points in time rather than only at the level of global traits.
Key findings include:
- Participants completed short questionnaires several times a day over three days, rating the extent to which they currently felt extraverted, anxious, friendly, and so on.
- In total, there were about 18,900 ratings from 1,725 people — providing statistical power to detect within-person changes.
- The study showed that individuals with higher levels of neuroticism displayed greater variability in emotions, particularly negative ones, as well as stronger reactivity to stressful events.
- Extraversion and openness also fluctuated depending on mood and social context — days of greater sociability and activity alternated with more introverted days.
- Traits like conscientiousness and agreeableness proved more stable, showing fewer short-term fluctuations.
What influences these daily fluctuations?
The data indicate that several factors play a significant role:
- Stress and negative events. For example, in a large-scale national study spanning nearly 20 years and tens of thousands of days, researchers found a link between how people reacted to daily stress and long-term shifts in extraversion, conscientiousness, and openness.
- Mood. A bad mood can amplify neuroticism, while a good mood boosts activity, friendliness, and openness. These effects are observed in short-term personality states.
- Social interactions and context. Being with others, engaging in conversations, and participating in activities can “switch on” traits like extraversion. A lack of social contact, on the other hand, often corresponds to a more withdrawn, “introverted” state.
- Long-term trends. Factors like age and life changes (work, relationships) influence more stable shifts in traits, gradually shaping a person’s average personality profile.
Why does this matter and what can we learn from it?
Understanding that personality can shift on a daily basis has several implications:
- Less self-criticism, more flexibility. Feeling more anxious or less sociable today may simply be a reaction to circumstances, not a “personal failure.” Recognizing this can help reduce anxiety and guilt.
- Better planning tailored to yourself. By noticing the situations in which you feel more energetic, open, or reserved, you can adapt your environment, schedule, and social activity to support more favorable states.
- Useful in therapy and self-help. Therapists can use diaries and state questionnaires to observe how traits manifest in daily life, how they change, and whether they get stuck in patterns due to chronic stress or negative moods.
- Advancing science. Studies like those using the FFM-PSI help create more accurate models of personality that account not only for averages (traits) but also variability (states) and situational context.
Limitations and caution
Despite impressive findings, it is important to keep in mind:
- Fluctuations are not the same as fundamental personality changes. Most shifts stay within a person’s characteristic range. Global traits remain more stable overall.
- Many studies rely on self-reports — people describe how they feel and perceive themselves, which can involve subjective biases.
- Results may not apply equally to individuals with psychological disorders, where stress levels and emotional variability tend to be consistently higher.
Conclusion
Personality is not a static “sculpture” but rather a living organism, constantly responding to what happens around and within us. Extraversion, neuroticism, openness, and other traits may manifest differently depending on situation, mood, social life, and stress triggers. Understanding this dynamic allows for more self-compassion, recognizing that “bad days” are not permanent, and using awareness to cultivate the personality states we want to nurture.
Disclaimer: This material is not medical advice. If you experience persistent difficulties with anxiety, mood, or self-perception, please consult a qualified psychologist or psychiatrist.
