Ratner and his colleagues decided to investigate the effect of negative stereotyping on brain processing in Latinx UCSB students, specifically Mexican American students. In their paper, the authors note that Mexican American people represent 63% of the U.S. Latinx population.
Ratner has done previous work on the fatiguing, depression-inducing effects of life stressors. “In work I was involved in over a decade ago,” he recalls, “we showed that life stress can be associated with anhedonia, which is a blunted sensitivity to positive and rewarding information, such as winning money.” It can be the anticipation of reward that motivates an individual to persist in the face of adversities.
Says Ratner, “If you’re not sensitive to the rewarding things in life, you’re basically left being sensitive to all the frustrating things in life, without that positive buffer. And that’s one route to depression.”
While other research has reported that exposure to stigma and discrimination can cause anger, racing thoughts, and even high arousal, Ratner is more interested in its exhausting effect on those who experience it. He notes that it can generate feelings of “oh, not again,” or “I’m so tired of this.”
For his experiments, Ratner and his colleagues recruited 40 self-identified Mexican American students from the UCSB psychology research subject pool. They randomly assigned the individuals to either the stigma condition or control group.
As the researchers tracked the participants’ brain activity using functional MRI (fMRI), both groups watched a rapid series of eight 2–3-minute videos regarding four subject areas:
- childhood obesity
- high school dropout rates
- gang-related violence
- teen pregnancy
For the stigma condition group, the selected videos discussed the four topics from the point of view of the Latinx community, suggesting that the problems were of particular concern to Latinx people, whom they disproportionately affect. However, “these videos were not overtly racist,” says Ratner.
The videos that the control group watched covered the same topics but as they related to the U.S. general population.
Immediately afterward, the participants completed a Monetary Incentive Delay (MID) task in which they had to push a button each time they saw a star displayed onscreen. Faster response times resulted in either winning money or avoiding financial penalties.
Individuals whom the team had shown stigmatizing video content proved to be significantly slower at this test than those in the control group.
“We saw that something about watching these stigmatizing videos was later influencing the pattern of response within [the nucleus accumbens] brain region,” says Ratner.
His interpretation is that the nucleus accumbens affected the participants’ attitudes toward financial loss or gain differently as a result of viewing the stereotyping videos. “The nucleus accumbens is very important for motivated behavior, and sparks of motivation are important for many aspects for everyday life,” he says.
When an individual feels caught in a situation that is out of their control, they may experience a loss of motivation. This feeling may be particularly difficult to overcome when it is the result of constant, insidious stereotyping that people see in the media and throughout popular culture.
“It becomes something you can’t escape — similar to other stressors that are out of people’s control and have been shown to cause anhedonia.”
“People shouldn’t generalize too much from this specific finding,” cautions Ratner, as the research focused solely on a single effect of stereotyping.
He also notes that the team only studied college-age individuals. Ratner is planning to conduct further experiments with a larger, more diverse cohort.
