The annual SXSW Festival was marred by controversy this week when a marketing company affixed wireless routers to homeless people to provide internet access to festival-goers. Critics said the plan—labeled a "charitable innovation experiment" by organizers—exploited the homeless and dehumanized them. Deplorable as the plan sounds, there is a deeper problem in the way people tend to perceive the homeless. As Nathan Hefleck of Psychology Today reports, neurological research conducted by RSF author Susan Fiske and other social psychologists has shown that people often view social "out-groups" as less than human:
[An] area of the brain called the Medial Prefrontal Cortex (mPFC) activates when people do things that involve perceiving and relating to other people, such as recognizing and distinguishing between faces and empathizing. These researchers hypothesized, however, that like objects such as tables, images of certain groups of people—the homeless—would fail to activate the mPFC.
This is exactly what they found. Images of all other groups besides the homeless activated the mPFC. This suggests that the homeless are not recognized as human relative to other groups. They actually are perceived, at least in this area of the brain, more like objects, such as tables.
Fiske elaborated on this finding in an interview with RSF Review last year:
Scorn is simply not paying attention and wishing the other away. Groups are scorned especially if they are low-status and not-us, such as homeless people and drug addicts. Poor people (regardless of ethnicity) and Latino immigrants are also seen this way. Scorn dehumanizes them and makes us neglect them.
What does it mean to 'dehumanize,' or perceive someone as less than human? In her RSF book Envy Up, Scorn Down, Fiske explained:
When we dehumanize people, we deny them not only typically human attributes such as warmth and familiarity, but also uniquely human attributes, such as subtle emotions, articulate language, and complex minds. As in the earlier work on denying subtle emotions to out-groups, Nick Haslam describes this form of dehumanization as likening people to animals. People all over the world associate certain kinds of out-groups with animals automatically, not deliberately.
You can read more about these findings in this study: Harris, Lasana T., and Susan T. Fiske. 2006. "Dehumanizing the Lowest of the Low: Neuro-imaging Responses to Extreme Outgroups." (PDF) Psychological Science 17 (10): 847-53.