2000). This research suggests that at least two interpersonal phenomena might affect the sensitivity and specificity of polygraph tests: stigma and expectancies.


Stigmas mark individuals who are members of socially devalued groups. Stigmas may be easily visible (e.g., gender, skin color, deformations of the body); not necessarily visible (e.g., socioeconomic status, religion); or usually invisible (e.g., sexual orientation, metaphysical beliefs, having been suspected of espionage). Many theorists have argued that stigmas cause perceivers to feel a sense of uncertainty, discomfort, anxiety, or even danger during social interactions (Crocker, Major, and Steele, 1998). Much recent physiological work also suggests that bearers of stigma are threatened during interactions with members of nonstigmatized groups. Recently, research has confirmed experimentally that both stigma bearers and perceivers exhibit cardiovascular patterns of response associated with threat during performance situations that are not metabolically demanding (e.g., Mendes, Seery, and Blascovich, 2000; Blascovich et al., 2001b). This research typically demonstrates these effects during task performance but not during baseline or resting periods, suggesting the possibility that physiological responses to relevant and comparison questions might be differentially affected on polygraph tests.

Research on members of racially stigmatized groups (particularly, African Americans) suggests that such individuals exhibit heightened cardiovascular threat responses in situations in which negative stereotypes about racially stigmatized groups are likely to exist (Blascovich et al., 2001a). For example, members of racially stigmatized groups exhibit increased blood pressure reactivity during testing that requires their cognitive responses to difficult test items.

The experimental situations in which these stigma studies have occurred bear a striking resemblance to polygraph testing situations, particularly employee screening tests. Participants are told the kind of tasks that they will undertake. Their written consent is obtained. Participants are given physiological tests in recording rooms. In most of these studies, participants are asked to cooperate with each other. Autonomic physiological sensors, including blood pressure cuffs, are attached to participants, and so forth.

One important difference between the testing situations in these studies and polygraph testing situations is that participants are not asked to lie. Neither are they told that the purpose of the physiological recording equipment is to detect lying (which it is not). Nonetheless, both perceivers and bearers of stigma, including visible and nonvisible stigmas, have

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