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Introduction: Non-suicidal self-injury (NSSI) is associated with a wide range of psychiatric disorders. Mentalization-based therapy (MBT) is a therapeutic approach that can possibly target the mechanisms involved in NSSI. The purpose of this study was to investigate the effect of mentalization-based therapy on dissociative experiences, alexithymia and impulsivity in people with non-suicidal self-injury.
Methods: The current research was a semi-experimental type of research with a pre-test-post-test design. Among the people who referred to the clinics and counseling centers of Tehran in 2023, 30 people who had obtained the highest score in the non-suicidal self-injury (NSSI) questionnaire were selected by convenience sampling method and randomly divided into two experimental groups and The control group (15 people) was replaced. The experimental group received 20 sessions of mentalization-based therapy, but the control group did not receive any specific intervention. The research tools were: non-suicidal self-injury questionnaire, Dissociative Experiences Scale, Toronto Alexithymia Scale and Barratt Impulsiveness Scale. Data were analyzed using multivariate analysis of covariance test.
Results: The results showed that there is a difference between the average scores of dissociative experiences, alexithymia and impulsivity in the experimental and control groups, so that the mentalization-based treatment reduces dissociative experiences, alexithymia and impulsivity in people with non-suicidal self-injury (P<0.05).
Conclusions: Mentalization-based therapy is an appropriate treatment method for improving dissociative experiences, alexithymia, and impulsivity in people with non-suicidal self-injury, and it can be used as an effective intervention method in the treatment of non-suicidal self-injury.