Sick in the head? Pathogen concerns bias implicit perceptions of mental illness

Area of Science:

• Evolutionary psychology
• Social psychology
• Psychopathology

Background:

• Stigma against individuals with mental illness is a pervasive global issue.
• Existing theories attribute this stigma to perceptions of danger and incompetence.
• An alternative hypothesis suggests stigma may be rooted in disease avoidance mechanisms.

Purpose of the Study:

• To investigate the role of the behavioral immune system in mental illness stigma.
• To test whether mental illness is implicitly associated with disease rather than danger.
• To examine how biological immune system activation influences this association.

Main Methods:

• Two experiments were conducted to assess implicit associations.
• Experiment 1 measured associations in individuals with recently activated biological immune systems.
• Experiment 2 used priming techniques to manipulate disease salience.

Main Results:

• Mental illness was implicitly associated more with disease than with danger.
• This implicit association was stronger in participants whose biological immune systems were recently activated.
• Priming disease concepts increased the implicit association between mental illness and disease.

Conclusions:

• Mental illness stigma may be partly explained by evolved biases to avoid contagion, mediated by the behavioral immune system.
• Findings suggest that disease avoidance, not just fear of danger, contributes to prejudice against the mentally ill.
• Understanding these evolutionary roots can inform strategies for reducing mental illness stigma.