ABSTRACT

The use of the polygraph or ‘lie detector ‘, for purposes of detecting deception has been the subject of social and academic controversy. Acceptance of the accuracy of the basis polygraph paradigms has been conditional upon agreement with the psychological theories underlying the test procedures. In this chapter a theoretical standpoint is proposed to reconcile and encompass both the accepted Guilty Knowledge Test and the contested Control Question Test, in one general theory. The Guilty Knowledge Test is considered in terms of Sokolov’s (1963) orienting response theory and Tversky’s (1977) contrast model of similarity. The (diagnosticity principle’ of Tver sky’s model serves as a bridge to the Control Question test, acting in concert with evaluative self-concepts, to explicate the resulting psychophysiological processes in this test paradigm. The cognitive and emotional processes included in the notion of self-concepts are relevant in considering the relationship between the significant cognitive constructs of offenders and the way in which they commit their offences.