Concealed Information Test: Theoretical Background

After six decades of research it has been well established that physiological measures can validly detect concealed memories. However, the exact theoretical underpinnings of concealed information testing remain to be elucidated. In the present chapter we review the various theoretical accounts of the Concealed Information Test (CIT) effect and discuss their development over time. We start with several unitary theories that each focus on a single emotional-motivational factor. As it appeared that such factors have little impact on the CIT, cognitive factors became the early focus of examination. The orienting response theory in particular has dominated the field for years. Although evidence suggests that orienting theory may well apply to the skin conductance measure, it may not fully explain physiological reactivity in the CIT for other response measures such as respiration and heart rate (HR). Hence, a response fractionation model that suggests that the skin conductance measure reflects orienting and the respiration and HR measures reflect attempts at arousal inhibition was proposed. Future work is needed to validate this model and test whether it holds under real-life circumstances. Furthermore, more research is needed to examine the underlying mechanisms of other physiological and behavioral measures.