Harada et. al. (Lecture 7-8)

What is the big-picture question and motivation of Harada et al. (2020)?

Whether culture and group membership shape neural processing of emotional faces, especially how in-group vs. out-group emotions are processed in the brain.

What was known before this study about culture, race, and facial emotion processing?

People recognize emotions more efficiently in faces from their own cultural or racial group, and the amygdala is sensitive to emotional and socially relevant stimuli.

What key gap in prior research does this study address?

Whether amygdala responses reflect cultural in-group relevance rather than race alone, particularly in bicultural individuals.

Why did the authors focus on the amygdala?

Because it plays a central role in detecting emotionally salient and threatening stimuli and has shown in-group sensitivity in prior studies.

How was group membership defined in this study?

By cultural background and social environment (Eastern vs. Western), not just racial appearance.

How was race incorporated into the experimental design?

Facial race was manipulated independently from participants’ cultural group to separate race from culture.

What task did participants perform in the MRI scanner, and why is it considered implicit?

A face-matching task that did not require explicit emotion judgments, allowing emotion processing to occur automatically.

What stimuli were used, and why were both types included?

Emotional faces (anger, fear) and neutral/control stimuli, to isolate emotion-specific neural responses.

How was collectivism measured?

Using self-report questionnaires assessing individualist vs. collectivist values.

What were the main behavioral findings (reaction time and accuracy)?

No meaningful group differences; performance was high across all groups.

What was the main behavioral finding regarding collectivism?

Eastern participants scored higher on collectivism, with bicultural participants showing intermediate levels.

What is the “cultural in-group effect” observed in the amygdala?

Stronger amygdala activation to angry and fearful faces from one’s own cultural group.

Which emotions primarily drove the amygdala in-group effect?

Threat-related emotions, specifically anger and fear.

How did bicultural participants’ amygdala responses compare to monocultural participants?

They showed intermediate levels of activation to both in-group and out-group faces.

What additional brain regions showed in-group effects in one participant group?

Medial prefrontal cortex and posterior cingulate cortex in Easterners living in the east.

In which group were these whole-brain effects observed?

Eastern participants living in their home culture (the east).

What do these whole-brain activations suggest about in-group emotional faces?

They are processed as self-relevant and socially meaningful.

How did the authors examine brain–behavior relationships with collectivism?

By correlating individual collectivism scores with neural activation levels.

Why are the brain–collectivism correlations methodologically problematic?

Because correlations appear driven by between-group clustering rather than within-group variation.

How do the authors interpret the overall significance of the findings?

Culture shapes early, automatic neural responses to emotional information.

How do the authors interpret enhanced amygdala responses to in-group faces?

In-group emotional signals carry greater social and adaptive importance.

What is the single most important conclusion of Harada et al. (2020)?

Cultural group membership modulates neural processing of emotional faces, particularly through enhanced amygdala responses to in-group threat signals.

What were the key independent (IV) and dependent (DV) variables in Harada et al. (2020)?

• IVs: Cultural group (Eastern, Western, bicultural), face group (in-group vs. out-group), facial emotion (anger, fear, neutral)

• DVs: Brain activity (amygdala & whole-brain), reaction time, accuracy, collectivism scores

Who were the participants in this study, and why were these groups important?

Participants were Western monocultural, Eastern monocultural, and bicultural individuals; this design allowed the authors to separate effects of race from cultural experience.

What is the hierarchy of results in order of importance?

• Cultural in-group effect in the amygdala for angry and fearful faces

• Bicultural participants showing intermediate neural responses

• Whole-brain self-referential activations in Eastern participants

• No meaningful behavioral performance differences