Table 1.
Reviewing amygdala activity across neuroimaging studies.
| References | Contrast | Participants | Target stimuli | Task | Technical details | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| N | Age | Race | Expression | Gender | Race | Hemisphere | Resolution | |||
| (A) UNILATERAL AMYGDALA MODULATION | ||||||||||
| (i) No significant effect | ||||||||||
| Hart et al., 2000 | Ingroup–Outgroup | 8 | 20–35 | B + W | Neutral | M + F | B + W | Male/Female | L | 3.13 × 3.13 × 3 |
| Phelps et al., 2000 | Black–White† | 14 | – | W | Neutral | M | B + W | Same/Different | n/a | 3.13 × 3.13 × 3 |
| Phelps et al., 2000 | Black–White (familiar) | 13 | – | W | Neutral | M | B + W | Same/Different | n/a | 3.13 × 3.13 × 3 |
| Cunningham et al., 2004 | Black–White† | 13 | 27 | W | Neutral | – | B + W | Right/Left | n/a | 3.13 × 3.13 × 6 |
| Richeson et al., 2003 | Black–White | 15 | 21 | W | Neutral | – | B + W | Right/Left | n/a | 3 × 3 × 3 |
| Richeson et al., 2003 | Black–White | 15 | 20 | W | Neutral | – | B + W | Right/Left | n/a | 3 × 3 × 3 |
| Wheeler and Fiske, 2005 | Black–White | 7 | – | W | Happy | – | B + W | Dot detection | n/a | 3.75 × 3.75 × 5 |
| Krill and Platek, 2009 | Other-same race† | 14 | 28 | W | – | – | B + W | Cyberball game | n/a | – |
| (ii) Significant increase | ||||||||||
| Lieberman et al., 2005 | Black–White | 20 | 24 | B + W | Neutral | M | B + W | Same/Different | R | 4 × 4 × 4 |
| Cunningham et al., 2004 | Black–White (subliminal)† | 13 | 27 | W | Neutral | – | B + W | Right/Left | R | 3.13 × 3.13 × 6 |
| Wheeler and Fiske, 2005 | Black–White | 7 | – | W | Happy | – | B + W | Age >21? | L | 3.75 × 3.75 × 5 |
| Ronquillo et al., 2007 | Black–White | 11 | 18–36 | W | Neutral | M | B + W | Age >24? | R | 4.5 × 4.5 × 3.5 |
| Ronquillo et al., 2007 | Dark–Light skin | 11 | 18–36 | W | Neutral | M | B + W | Age >24? | R | 4.5 × 4.5 × 3.5 |
| (iii) Significant decrease | ||||||||||
| Lieberman et al., 2005 | Verbal Black–White | 21 | 25 | B + W | Neutral | M | B + W | Verbal Same/Diff. | R | 4 × 4 × 4 |
| Wheeler and Fiske, 2005 | Black–White | 7 | – | W | Happy | – | B + W | Like/Dislike Veg? | R | 3.75 × 3.75 × 5 |
| (B) BILATERAL AMYGDALA MODULATION | ||||||||||
| (i) Significant increase | ||||||||||
| Richeson et al., 2008 | Black–White (direct gaze) | 9 | 19–23 | W | Neutral | – | B + W | Right/Left | R + L | 3 × 3 × 3 |
| Demos et al., 2008 | Dilated-normal pupil | 27 | 22 | – | Neutral | F | W | Passive viewing | R + L | 3 × 3 × 3 |
| Telzer et al., 2013 | B-W correlation with age | 32 | 4–17 | M | Varied | – | B + W | Same/Different | R + L | 3 × 3 × 3 |
| (ii) No significant effect | ||||||||||
| Richeson et al., 2008 | Black–White (averted gaze) | 9 | 19–23 | W | Neutral | – | B + W | Right/Left | n/a | 3 × 3 × 3 |
Section A highlights inconsistent, unilateral activity across race-related social neuroscience studies. Section B highlights results showing bilateral amygdala activity. Importantly, Target stimuli gender is rarely reported, precluding discussion of differences in activity toward Black men vs. Black women.
General: “–” for information not disclosed in articles. Contrast: “
†
” indicates reported positive correlation between B-W difference and Implicit Prejudice (IAT). Participants: Range given for age where mean not reported. Technical: Resolution as dimensions of one voxel in mm, compared to the ~1200 mm3 volume of the amygdala. All studies conducted in USA.