The aim of the present study was to examine how a person with amnestic mild cognitive impairment perceives the phenomenon of deception. Amnestic mild cognitive impairment (aMCI) usually represents the prodromal phase of Alzheimer's disease (AD), with patients showing memory impairment but with normal activities of daily living. It was expected that aMCI patients would face difficulties in the attribution and interpretation of deceptive behavior due to deficits regarding their diagnosis. The main sample of the study consisted of 76 older adults who were patients of a daycare center diagnosed with aMCI. A sample of 55 highly educated young adults was also examined in the same experiment to qualitatively compare their performance with that of aMCI patients. Participants were assigned a scenario where a hypothetical partner (either a friend or a stranger) was engaged in a task in which the partner could lie to boost their earnings at the expense of the participant. The results showed that aMCI patients, even if they understood that something was going wrong, did not invest in interpretations of potential deception and tended to avoid searching for confirmative information related to the hypothetical lie of their partner compared to highly educated young adults. It seems that aMCI patients become somehow "innocent", and this is discussed in terms of cognitive impairment and/or socioemotional selectivity.
Keywords: deception; dishonesty; executive functions; theory of mind (ToM).