Dehumanizing the lowest of
the low. Neuroimaging
responses to extreme
outgroups Lasana T Harris
Susan T. Fiske
 The authors of this study posit that extreme outgroups as defined by the Stereotype Content Model
(more on that next) will be perceived to be less than
human by participants and that this
dehumanization will be manifested in neural
activity patterns
*
The Stereotype Content Model
(SCM)
SCM is a psychological theory the breaks the content of stereotypes into 2
categories
1.) Warmth (high or low)
A fundamental friend or foe judgment
Help or harm?
2.) Competance (high or low)
A judgment on how capable one is at acting out intentions
Combinations of high and low Warmth and Competance results in 4
possible clusters people may fall into and defines how we observe
them.
The SCM also attributes a general emotion to each of
these groups.
(Note the object controls)
 The present study attempts to affirm this prediction
through the measuring of neural responses in the
presence of visual stimuli containing individuals in
various SCM groupings
 Brain Areas focused on were the
 Medial Prefrontal Cortex (social cognition)
 The Amygdala (emotional memory and processing)
 The Insula (emotion and homeostatic maintenance)
 The SCM predicts that extreme out-groups, those
with low warmth and competence will be
dehumanized.
Method
-Overview Participants saw images of different
 Social groups in Study 1
 Objects in Study 2
Then made an affective assessment of each picture while in
an fMRI.
 For example,
 Participants were shown an image of a disabled
person and then decided which of the 4 SCM
emotions they felt most in response while their BOLD
signals were measured.
Method
-Participants 22 Princeton undergrads
 12 women
 Mean age: 19.5
 6 ethnic minority
 No mental deficits

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
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Lesions
Brain damage
Left handedness
Neurological disorder
Method
-Stimulus STUDY 1 - 48 colour photographs of 8 social groups
 Images selected from an initial 80 photographs that 254
undergraduated rated in terms of each SCM emotion.
 Only those with significant elicited unique emotion were selected
and the other 32 were dropped.
STUDY 2 parameters.
8 images of objects were selected via previous
Method
-Procedure1.) Before entering scanner, participants practiced
rating neutral landscapes on each SCM emotion
(pride, envy, pity, disgust) on a computer
2.) Inside scanner, photographs were presented in six
runs each containing 10 pictures
Method
-ProcedureStudy 1
Study2
1.) Picture presented
6s
4s
2.) Affect Response screen
2s
4s
3.) Green fixation delay cross
11s
11s
4.) Red warning cross
1s
1s
Each photo was presented 1 time in Study 1 and 3 times in
Study 2
Method
-Procedure After scanning session
 Participants saw same stimuli on grey scale pictures
 They rated each picture along a 5 point scale for each
SCM emotion.
 Also relayed what additional emotions they felt after
viewing the pictures
Method
-Procedure Participants were then probed for suspicion
-None were deemed suspicious
*
Results
Study 1 pt. 1
 Emotional judgments made by participants in
agreed with those predicted.
(participants in scanner gave same ratings as the
original 254 raters)
 mPFC activity was significantly above baseline
levels for all clusters save the disgust group (lowlow).
 Positive t values represent higher activity during stimulus
presentation.
Results
Study 1 pt.2
 Instead, for the disgust (low-low) cluster, significant
activity was measured in the
Left Insula
+
Right Amygdala
Consistent with
Disgust
responses to objects
Study 2 Results
Able to see right amygdala and left insula activations
Discussion pt. 1
As hypothesized
 Some social groups appear to be dehumanized
 At least by absence of typical neural signature for social
cognition and increased amygdala and insula activations.
It is also important to note not all out
groups are necessarily dehumanized.
Discussion pt. 2
Justifying the disgust association
Essentially a statistical review
“In addition, the low-low quadrant differentially
elicits neural patterns consistent with disgust (insula)
and fear (amygdala), according to meta-analyses
Murphy, Nimmo-Smith, & Lawrence, 2003; Phan,
Wager, Taylor, & Liberzon, 2002”
Discussion pt. 3
The current results empirically support the idea of
dehumanization and are consistent with verbal reports. By
providing neural evidence of the phenomenon, these data go
beyond verbal reports, which may be subject to selfpresentational concerns.
Furthermore, if replicated and extended, this kind of
evidence could begin to help explain the all-too-human
ability to commit atrocities such as hate crimes, prisoner
abuse, and genocide against people who are dehumanized
Criticisms
-Some of the figures left you to figure out their meaning
somewhat
-Didn’t consider much past their own study in discussion
-Left me wanting for conditions and contexts that may
garner this phenomenon.
Paper was perhaps too abstract in contrast to
very real consequences
-Perhaps for another paper (not even sure if this would be
legal or allowed) run experiments that could elicit these
neural patterns
Paper Pros
 Relevant
At least from a layman’s perspective; this is the bread and
butter of psychology
 Concise/clear
It was not that long. They left out their results and methods
that did not yield significant results.
Interesting
 “Out-group dehumanization is at least as old as the U.S.
Constitution1 and as modern as current forms of
dehumanization, described by out-group infrahumanization
theory”
 Turns out dehumanization is only a couple hundred years
old. Nice
 The parameters presented for dehumanization of extreme
out groups fall far across a spectrum that definitively
exceeds those defined by the history of the United states.
What garners
dehumanization?
 http://www.ted.com/talks/philip_zimbardo_on_the_p
sychology_of_evil.html
 Context
 System
 Extremism
 Focusing on differences between groups
 Demonizing other groups
Fin
“Where is your concluding image?”
Jack
Thomson
 Link to main paper:
 http://pss.sagepub.com/content/17/10/847.short
Literature and Political
Science
 Lord of the flies
 Heart of Darkness
 Clash of Civilizations
 Orwell
 Themes of dehumanization run through these
hugely popular works
 None of them needed a brain scan to figure this out.
Other interesting papers
 How ordinary people torture enemy prisoners
 http://www.sciencemag.org/content/306/5701/1482
.full
 Dehumanization in the Health Care system
 http://pps.sagepub.com/content/7/2/176.full