Environmental Sensitivity in Japanese and United States Samples: Cross-Cultural Investigation of Its Measurement and Associations with Personality and Affect

People differ in their susceptibility to both negative and positive environmental influences. Environmental Sensitivity is a framework that explains such individual differences, and its phenotypic trait can be measured using the Highly Sensitive Person (HSP) scale. From the cultural/ethnic differences perspective, this study investigates the measurement invariance of the HSP scale and its associations with the Big Five personality traits and Negative/Positive Affect using samples from Japan and the United States. Participants from Japan (n = 531, Mage = 20.6 ± 1.5 years) and the United States (n = 480, Mage = 20.8 ± 2.2 years) completed an online questionnaire survey. Multi-group confirmatory factor analysis provided evidence for partial scalar invariance of the HSP scale across the samples, suggesting that the measurement of sensitivity is largely consistent across countries. Sensitivity was negatively correlated with Conscientiousness only in the Japanese sample, while higher sensitivity was associated with lower Extraversion and higher Neuroticism in both samples. Similar trends were observed in both samples for the correlations between sensitivity and Negative/Positive Affect. These findings suggest that psychological characteristics related to sensitivity may vary partially between countries with different cultural values. Our study offers insights for future research on cultural/ethnic differences in sensitivity.