It seems that this week’s readings largely focused on the amygdala, though I was happy that the Amodio et al. (2004) article discussed the ACC, which intuitively seemed like a relevant area when discussing race bias and stereotypes. Phelps, Cannistraci, and Cunningham (2003) provide a succinct overview of past research findings concerning the amygdala with a great definition of it as “a small, almond-shaped structure in the medial temporal lobe that is primarily known for its role in emotional learning and memory” (pp. 203). They also cover the research that has shown that the amygdala is typically linked with automatic responses, an important point considering that most of this week’s articles addressed automatic, implicit processes.
Although their literature review of different findings related to amygdala activation in response to race evaluations is quite good, Phelps et al. (2003) should probably be titled, “Read with extreme caution: We have the lowest N of any study you’ve read yet.” Basically, the researchers included one amygdala-lesion patient and a total of 2 controls to evaluate whether or not the amygdala plays a role in explicit racism and implicit racial associations. To be fair, this was done in an effort to support past imaging data, but it is reported separately for I have no idea what reason. The findings showed that the amygdala does not play a role in responses to the Modern Racism Scale (conscious, self-report measure on which high scores suggest anti-Black beliefs and attitudes) or to the IAT, which utilized Black and White male faces in this study. This is concluded because there was no difference between the patient’s responses and the other 2 participants. Like I said, interpret at your own risk.
Phelps et al. (2003) do touch upon the role of the FFA in race evaluations and how the FFA is used more often with in-group faces, which is assumed to evidence familiarity and “expertise” in own race face evaluations. This brings me to a point that Jenny mentioned – namely, in many of these studies, differential amygdala activation in the perception of Black and White faces is taken as evidence of racism. The one problem that stares me in the face as a social psychologist is familiarity with the majority (White) and the minority (in this case, Black). It seems that the majority of these studies never give participants a simple measure of how often they interact with individuals of other ethnicities and what types of experiences they have had with them. It should be noted that the Wheeler and Fiske (2005) has participants list the first 20 acquaintances that come to mind and the ethnicities of each, yet they don’t discuss it further than that (whether due to non-significance or their disinterest, it is not apparent). Their may be work out there that shows that familiarity doesn’t play a role. I’ll admit that I just don’t know, but I still wish that it was an issue discussed or touched upon by the authors.
Switching gears a bit - the Wheeler and Fiske (2005) article was designed to test how different social processing goals impact amygdala activation in response to Black and White faces. The main reason is that although stereotype knowledge and prejudice varies between individuals, work has shown that a person’s current processing goals can also impact category-based responses. In the first neural imaging study (N = 7), it was found that social categorization by age resulted in greater activation, whereas social individuation (as indexed by vegetable preference) resulted in decreased amygdala activation. Activation was in comparison to a neutral dot search task in the faces. In experiment 2, participants (N = 42) performed a lexical decision task after priming with stereotype relevant or irrelevant words. It was unclear how these words were derived and from my reading may be subject to the region’s specific prejudices. For example, “loyal” is not specifically a racially focused word in my opinion so I wish they would have included more about that. On the note of results, it was found that only after engaging in a social categorization of Black faces, rather than a social individuation or neutral search task did response times to stereotype-relevant words show greater speeds.
One of the more interesting studies for this week was Lieberman, Hairi, Jarcho, Eisenberger, and Bookheimer (2005). In contrast to past work, this study found that both Black and White participants showed greater amygdala activation in response to White faces on a perceptual processing task but not a verbal processing task. Somehow these researchers failed to report their sample size, which I would have liked to see so I could base how strongly I should consider these results. At the same time, the authors highlighted that this pattern of activation may suggest that both Black and White individuals are aware of the negative stereotypes towards Blacks in American culture.
This week I focused on the Correll, Urland & Ito (2006) article. This study looked at event-related potentials and the role of threat perception (P200 response) and cognitive control (N200 response) in the decision to shoot targets either Black or White targets. The authors believe that due to racial stereotype linking Blacks to danger, a Black target automatically activates the idea of danger and predisposition to shoot. The term shooter bias is used throughout the paper refers to the decision to shoot armed targets more quickly and to not shoot unarmed targets less quickly if they are Black compared to if they are White.
The study included 40 right-handed participants. ERP data was collected while participants played a video game consisting of 80 randomly ordered trials. After a fixation cross, a target person appeared and participants had 850ms to press a button indicating the decision to shoot or another to indicate the decision not to shoot. The top three performers received $30, $15 & $10 that was calculated through the use of a point system. Also, participants (31 of them) completed a questionnaire assessing their perception of the personal and cultural stereotype associating Blacks with aggression, violence and danger. The authors hypothesized greater P200s and smaller N200s when participants were making shoot/don’t shoot decisions with Black relative to White targets.
The results include the following:
· Significant interaction of Target Race and Object Type supporting shooter bias (shot armed Black targets and didn’t shoot non-armed White targets the quickest). However, Race by Object interaction was not significant in the P200 or N200
· Larger P200s and Smaller N200s for Blacks relative to Whites
· In the P200 and N200, responses to unarmed Whites were significantly different than responses to all other targets and there was NO significant difference between responses to unarmed Blacks compared to armed Blacks and Whites
· Cultural stereotypes predicted both the early ERP (P200 and N200) racial differentiation and racial bias in the game
Overall, it was a fascinating study and I thought there was greater ecological validity in using a video game for the stimulus. However, in future research I would suggest giving the questionnaire (which needs to be described better, as it is very vague) to all the participants (only gave it to 31 out of 40), and assessing stereotypes implicitly (responses could be affected by social desirability). The significant relationships between the questionnaire and ERP activity were only for questions regarding cultural stereotypes, but more interesting would be whether personal stereotype can predict ERP activity and behavioral bias. An implicit measure of personal stereotype would be more appropriate. The authors also only got demographic information on the 31 participants who completed the questionnaire and failed to address whether racial differences in ERP activity might exist. Also, it would have been interesting to use both Black and White participants and compare differences in ERP activity and shooter bias.