Less than human: Dehumanization underlies prejudice toward people with developmental disabilities

Laura Ruth Murry Parker, Purdue University


The present research examined the nature of prejudice toward people with developmental disabilities, its underlying root in dehumanization and implication for opposition to social policies, and the efficacy of two strategies for reducing this bias. In Study 1 and Study 2, dehumanization significantly predicted both greater prejudice and greater opposition to social policies benefiting people with Autism and Down Syndrome. Furthermore, prejudice significantly mediated the effect of dehumanization on social policy support. Dehumanization predicted greater prejudice, which led to less support for social policies. Building on the consistent association between dehumanization and prejudice in the first two studies, Study 3 examined whether either humanizing or individuating a person with Autism or Down Syndrome would reduce prejudice and opposition to social policies toward the groups more broadly. Both humanizing and individuating a single person led to significant reductions in dehumanization of and prejudice toward the target group, relative to a control condition, and also increased support for social policies benefiting the group. A multiple mediation analysis suggested that these interventions reduced dehumanization, which reduced prejudice, and ultimately reduced opposition to social policies. This research illustrates the potential utility of humanization and individuation to reduce prejudice and mistreatment of people with developmental disabilities.




Monteith, Purdue University.

Subject Area

Behavioral psychology|Social psychology

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