Immediate reward bias in adolescent non-suicidal self-injury: Evidence from delay and probability discounting tasks

Non-suicidal self-injury (NSSI) constitutes a major public health concern among adolescents. Although impulsivity is a recognized risk factor, its specific role in value-based decision-making remains elusive. This study examined delay and probability discounting patterns in adolescents with NSSI compared to healthy controls across both gain and loss domains, identifying specific decision-making alterations associated with self-injurious behavior.

Eighty-two adolescents (42 with NSSI absent of psychiatric comorbidities and 40 healthy controls) completed computerized delay and probability discounting tasks. Both tasks assessed decision-making using hypothetical monetary gains and losses. Discounting rates were quantified using area under the curve analyses.

For delay discounting, adolescents with NSSI discounted delayed gains more steeply than healthy controls, reflecting a stronger preference for immediate rewards. In contrast, group differences for delayed losses were non-significant and statistically equivalent to zero. Furthermore, no significant group differences emerged for either gains or losses in the probability discounting task.

The cross-sectional design, the modest sample size, and the reliance on hypothetical rather than real-world monetary outcomes limit ecological validity and constrain causal inference.

These preliminary findings suggest that NSSI in adolescents may be associated with a preferential sensitivity to reward immediacy, rather than generalized deficits across all decision-making domains. This behavioral profile supports models conceptualizing NSSI as an emotion-regulation strategy prioritizing immediate relief over long-term benefits, highlighting delay tolerance as a potential target for intervention.