Transcultural differences in brain activation patterns during theory of mind (ToM) task performance in Japanese and Caucasian participants

Abstract

Background: Theory of mind (ToM) functioning develops during certain phases of childhood. Factors such as language development and educational style seem to influence its development. Some studies that have focused on transcultural aspects of ToM development have found differences between Asian and Western cultures. To date, however, little is known about transcultural differences in neural activation patterns as they relate to ToM functioning.

Experimental methods: The aim of our study was to observe ToM functioning and differences in brain activation patterns, as assessed by functional magnetic resonance imaging (fMRI). This study included a sample of 18 healthy Japanese and 15 healthy Caucasian subjects living in Japan. We presented a ToM task depicting geometrical shapes moving in social patterns. We also administered questionnaires to examine empathy abilities and cultural background factors.

Results: Behavioral data showed no significant group differences in the subjects' post-scan descriptions of the movies. The imaging results displayed stronger activation in the medial prefrontal cortex (MPFC) in the Caucasian sample during the presentation of ToM videos. Furthermore, the task-associated activation of the MPFC was positively correlated with autistic and alexithymic features in the Japanese sample.

Discussion: In summary, our results showed evidence of culturally dependent sociobehavioral trait patterns, which suggests that they have an impact on brain activation patterns during information processing involving ToM.

Keywords:

• Transcultural
• fMRI
• Theory of mind
• MPFC
• Sociocultural background

Acknowledgments

The study was supported by a research fellowship from the Japan Society for the Promotion of Science (JSPS) (PE 07550 to K.K.); a grant for the initiation of bilateral cooperation from the DFG (German Research Foundation) (KO 4038/1-1 to K.K.); grants-in-aid for scientific research from the Japan Society for the Promotion of Science (21890119 to J.M.) and the Ministry of Education, Culture, Sports, Science and Technology, Japan (20691401 to T.M.); a grant from the Ministry of Health, Labor and Welfare, Japan (20E-3 to T.M.); a research grant from the Research Group for Schizophrenia sponsored by Astellas Pharma, Inc.; and a research grant from the Mitsubishi Pharma Research Foundation. We are grateful to all of the subjects for their participation in this study and to the staff involved in data acquisition. We would also like to thank Christoph Paulus of the University of Saarbrücken, Germany, for his helpful suggestions on the German version of the IRI.