background  Patients involved in brain injury litigation and suspected criminals often pretend they are suffering from cognitive disorders. Whereas patients involved in brain injury litigation may exaggerate or fake symptoms for financial reasons, suspected criminals may feign amnesia or other cognitive disorders in order to get a reduced sentence.
aim  To review both the prevalence of malingering among persons with a cognitive dysfunction and the techniques for detecting malingering.
method  PsychINFO and Medline were used to selectively review the literature on (a) the prevalence of simulated cognitive disorders among patients engaged in litigation and among suspected criminals, and (b) techniques for detecting such malingerers.
results  A considerable number of patients involved in brain injury litigation pretend they have a cognitive dysfunction. It may be possible to detect malingerers on the basis of specialised tests and questionnaires. Suspected criminals frequently feign amnesia with regard to a crime in which they have been involved. To find out if such amnesia is organic or simulated, one needs to be able to identify the special features of organic amnesia. Fortunately, there is a special procedure called Symptom Validity Testing, that can be used to establish whether such amnesia is genuine or feigned.
conclusion  Clinicians should seriously consider the possibility that patients involved in brain injury litigation and suspected criminals may simply be pretending they have cognitive disorders. Specialised tests, questionnaires and procedures may have a useful role to play in the detection of simulated cognitive disorders.