Cultural Hearts and Minds: A Cross-Cultural Examination of Emotion

Suppression in Complex Brain Networks

Ryan Hampton

Cultural Hearts A large cultural survey of 23 countries by

Matsumoto, Yoo, & Nakagawa (2008) showed that Japanese (M=3.96) were more likely to use Emotion Suppression techniques than Americans (M=3.27) and this trend was consistent among other collectivistic and individualistic cultures, respectively.

So it is suggested that collectivists are more likely to utilize emotion suppression strategies in regulation.

Cultural Hearts in the Mind Goldin, McRae, Ramel, & Gross (2008) found that

for an American sample, participants’ activation in the amygdala was greater when they suppressed emotional experiences.

Contrarily, Ohira et al. (2006) found the opposite for Japanese participants in which amygdala activation was almost completely absent when they suppressed emotional experiences.

However, no one has ever directly compared cross-cultural samples in a single study on this…or have they?

Curse you Joan Chiao! An article I recently

read cited something in press by Dr. Joan Chiao from Northwestern University which may have done this already…

When I say ‘Minds’ I mean ‘Brains’ Network Science! Turning brains into

complex networks where voxels are nodes and functional connections are edges.

Basic metrics: • Degree • Clustering/Local

Efficiency • Path Length/ Global

Efficiency • Assortativity

Image from Bullmore & Sporns (2009)

What part of the brain? For resting state data we are looking at what

is called the Default Mode Network (DMN) which is your network that is active when you are inactive.

Includes: • Precuneus • Medial

Prefrontal Cortex

• Bilateral Inferior Parietal Cortex

What I’ve got so far: Degree Average degree was significantly higher for Americans

(M=55.6491) than Chinese (M=53.7148), p<.001

Chinese American

Whaaaa? Right prefrontal cortex?! Chinese (M=122) degree in the rPFC was marginally

higher than Americans (M=74), p=.058. But what is important is that the Chinese very consistently have high degree nodes in this area.

Chinese Americans

What I’ve found so far: Local Efficiency, Clustering, and Assortativity Americans (M=.3748) have significantly

higher clustering coefficients than Chinese (M=.3122), p<.001

Americans (M=.5547) have significantly greater local efficiency than Chinese (M=.4567), p<.001

Americans (M=.5386) have significantly greater assortativity than Chinese (M=.4458), p<.001

What I’ve found so far: Global Efficiency and Path Length

No significant differences were found between Americans and Chinese (p’s>.17) in whole brain metrics but…

Chinese Americans

What I’ve found so far: Modularity Modularity is tricky. Technically, calculating

Modularity is an NP-Hard problem. So we estimate how areas fall into modules.

The consistency of modularity across participants tend to show a greater number of areas included in the DMN module in Americans than Chinese

Scaled Inclusivity: a measure of modular consistency

Chinese American

What I’ve found so far: Functional Cartography

FC tells us about different kinds of hubs!

What is interesting is not so much the number of hubs the proportion of connector hubs (CH) to provincial hubs (PH) in the network. Whereas Chinese have a ratio approximately 3 CH for every 10 PH, Americans tend to only have 2 CH for every 10 PH. This is a non-significant trend (p=.175) but contains several extreme outliers so including the other 20 images may show a significant effect.

Image from Bullmore & Sporns (2009)

Typical Cross-Cultural Differences Typically, collectivists (Chinese) have more

integrative self-concepts, even nuerologically (Zhu, Zhang, Fan, & Han; 2007)

They have more global (vs. focused) image processing (I forget who did this but can find out if interested)

They avoid committing the Fundamental Attribution Error by integrating situational information effectively (Krull, Loy, Lin, Wang, Chen, Zhao; (1999)

The American Brain Network Characterized by: More connections (not necessarily good) More local, concentrated processing (less

integrative) More interconnecting of high degree nodes (rich

club phenomenon) A DMN network of more areas working in a

focused mini-network that is less connected to the rest of the network (indicated by both lower concentrations of global efficiency in DMN areas and hub ratio)

The Chinese Brain Network Characterized by: Less connections (more efficient connections) Less local, concentrated processing (more

integrative) Less interconnecting of high degree nodes (less

redundancy) A DMN network with fewer areas in a more

diffuse mini-network that is more connected to the rest of the network (indicated by greater global efficiency in DMN areas and higher hub ratio)

What else can we learn from this? What are brain networks like when people are

engaged in an emotion suppression task? Are these ^ networks different across cultures? Can we explain cultural differences in other

neurological measures through these network differences?

Will we replicate possible cultural differences in neurological measures of emotion suppression?

And a whole host of other Network Science metrics that have to be examined.

References Bullmore, E., & Sporns, O. (2009). Complex brain networks: graph theoretical analysis of structural and functional systems. Nature reviews. Neuroscience, 10(3), 186–98. doi:10.1038/nrn2575 Goldin, P. R., McRae, K., Ramel, W., & Gross, J. J. (2008). The neural bases of emotion regulation: reappraisal and suppression of negative emotion. Biological psychiatry, 63(6), 577–86. doi:10.1016/j.biopsych.2007.05.031 Krull, D. S., Loy, M., Lin, J., Wang, C., Chen, S., & Zhao, X. (1999). The fundamental fundamental attribution error: Correspondence bias in individualist and collectivist cultures. Personality And Social Psychology Bulletin, 25(10), 1208-1219. doi:10.1177/0146167299258003 Matsumoto, D., Yoo, S. H., & Nakagawa, S. (2008). Culture, emotion regulation, and adjustment. Journal of personality and social psychology, 94(6), 925–37. doi:10.1037/0022-3514.94.6.925 Ohira, H., Nomura, M., Ichikawa, N., Isowa, T., Iidaka, T., Sato, A., Fukuyama, S., et al. (2006). Association of neural and physiological responses during voluntary emotion suppression. NeuroImage, 29(3), 721–33. doi:10.1016/j.neuroimage.2005.08.047 Zhu, Y., Zhang, L., Fan, J., & Han, S. (2007). Neural basis of cultural influence on self-representation. NeuroImage, 34(3), 1310–6. doi:10.1016/j.neuroimage.2006.08.047