Language Matters: Stability and/or Change of Personality Traits in Bilingual Sample

This study examines how language influences personality assessment outcomes in bilingual individuals by comparing responses to standardized instruments administered in both English and Bulgarian. A community sample of 236 Bulgarian-English bilinguals (Mage = 32.89, SD = 9.61), who used English daily for at least two years, completed four personality measures in both languages during a single session, with a music-based cognitive task break in between to reduce translation effects. Overall, results showed strong equivalence between language versions. However, subtle differences emerged, particularly in subscales related to reality testing, reflective functioning, and detachment – suggesting that certain self-perceptions may be more nuanced or emotionally resonant when assessed in the mother tongue. Age-related differences in Negative Affectivity were significant only in the Bulgarian version, aligning with developmental theories that highlight emotional and personality shifts during emerging adulthood. These findings support psychodynamic perspectives emphasizing the emotional depth and symbolic richness of the native language. Clinically, they underscore the importance of considering language preference and emotional comfort in bilingual assessments and therapeutic contexts. Future research should explore these effects in clinical populations and investigate how language shapes psychological expression and therapeutic outcomes.