Behavioral Economic Profiles in Theft Recidivists with and without Kleptomania

Recurrent theft, such as shoplifting, is a devastating social problem that poses a significant economic burden on society. However, the neurobehavioral mechanisms underlying such criminal offenses remain barely understood. Here we investigated the behavioral economic profiles of theft recidivists (TR) with and without kleptomania. To identify the decision-making processes underlying stealing behaviors, the hypothetical purchase task and the balloon analogue risk task (BART) structured with gain and loss frames were administered, along with concurrent measurement of prefrontal cortex (PFC) activity during the BART using functional near-infrared spectroscopy. TR with kleptomania demonstrated heightened loss aversion and price sensitivity (elasticity) compared to TR without kleptomania and control subjects with no criminal records, with a significant correlation between these factors, suggesting that heightened loss aversion may contribute to higher elasticity. Moreover, the relative loss-to-risk aversion ratio was found to be positively and negatively associated with the right and left PFC, respectively, suggesting that an imbalance between left and right PFC activity may be involved in the altered behavioral economic profiles. These findings challenge the conventional view of theft as a reward-seeking behavior, revealing that an abnormally inflated fear of monetary loss may play a role in recurrent stealing in kleptomania. SIGNIFICANCE STATEMENTTheft-related crimes, such as shoplifting, constitute a serious social issue that results in significant economic losses. However, little is known about the neurobehavioral mechanisms underlying theft actions. This study found that individuals who repeatedly steal due to kleptomania exhibited excessive loss aversion, making them hypersensitive to price fluctuations when purchasing goods. Furthermore, the study revealed a potential link between this excessive loss aversion and an imbalance in left and right prefrontal cortical activity. These findings suggest that some cases of habitual thieves stem from altered behavioral economic characteristics that differ significantly from the conventional image of theft driven by the pursuit of profit.