Deception detection with behavioral, autonomic, and neural measures: Conceptual and methodological considerations that warrant modesty

The detection of deception has attracted increased attention among psychological researchers, legal scholars, and ethicists during the last decade. Much of this has been driven by the possibility of using neuroimaging techniques for lie detection. Yet, neuroimaging studies addressing deception detection are clouded by lack of conceptual clarity and a host of methodological problems that are not unique to neuroimaging. We review the various research paradigms and the dependent measures that have been adopted to study deception and its detection. In doing so, we differentiate between basic research designed to shed light on the neurocognitive mechanisms underlying deceptive behavior and applied research aimed at detecting lies. We also stress the distinction between paradigms attempting to detect deception directly and those attempting to establish involvement by detecting crime-related knowledge, and discuss the methodological difficulties and threats to validity associated with each paradigm. Our conclusion is that the main challenge of future research is to find paradigms that can isolate cognitive factors associated with deception, rather than the discovery of a unique (brain) correlate of lying. We argue that the Comparison Question Test currently applied in many countries has weak scientific validity, which cannot be remedied by using neuroimaging measures. Other paradigms are promising, but the absence of data from ecologically valid studies poses a challenge for legal admissibility of their outcomes.