Editor's Note: the content of this Web article may be triggering for those who self-injure.
What causes SI?
As the previous paragraphs suggest, a brain chemical imbalance may be implicated in SI, but its causes are not understood at this point. It appears as a behavior in connection with a number of diagnoses, including:
As previously noted, the variety of diagnoses with which SI is associated has suggested to some researchers that it may merit a separate personality disorder designation of its own.
The most frequent diagnosis associated with SI is Borderline Personality Disorder (BPD)—probably the most controversial designation in the authoritative Diagnostic and Statistical Manual of Mental Disorders—Fourth Edition (DSM-IV). Someone suffering from BPD is characterized by erratic impulse control, unstable interpersonal relationships, rapidly shifting moods and unstable self-image.
A diagnosis of BPD requires that the patient meet five of nine criteria, based on long-term behavior, beginning by early adulthood:
Those who challenge the frequency of BPD diagnosis point out two weaknesses in its use:
· It is applied to adolescents, ignoring the stipulation that diagnoses of personality disorders must address behavior that has persisted for a long time
· If SI behavior is removed as a criterion, only a minority of those diagnosed with BPD still meets the requirement of five of the nine criteria.
In other words, they object that the BPD diagnosis is made too quickly, and that it is too readily applied when the principal symptom prompting it is SI. This is not a minor issue, since a diagnosis of BPD has a significant stigma attached to it within the psychological community. Patients suffering from it are often considered so impulsive, emotionally needy, retaliatory and otherwise difficult to deal with that some clinicians even refuse to treat them.
There is also a perception among critics that the far higher incidence of BPD in women has made that diagnosis something of a self-fulfilling prophesy—a woman presenting with SI behavior is summarily diagnosed with BPD without adequate attention to the accepted criteria.
There is substantial statistical evidence of a link between SI and childhood physical and sexual abuse and emotional neglect. Childhood abuse is also a recognized cause of post-traumatic stress disorder (PTSD), depression, anxiety and dissociation, all of which are also associated with SI.
Past traumatic events, in short, provide a strongly unifying element in the evolution of SI, though not all SI can be traced to childhood trauma, and some research has failed to confirm the link in certain classes of SI sufferers.
 See footnote 7 for reference
 Adapted from Morrison, J.,DSM IV Made Easy: The Clinician's Guide to Diagnosis Complete DSM-IV Diagnostic Criteria: Personality Disorders, Guilford Press, 1995, available at http://mysite.verizon.net/res7oqx1/id16.html. Accessed 1/6/2005
 This issue is discussed at some length in Secret Shame Diagnoses associated with self-injury, pp. 2-3
 Van der Kolk, B., Perry, J., and Herman, Childhood origins of self-destructive behavior, American Journal of Psychiatry, 1991: 148: 1665-1671, cited in Secret Shame: Etiology of SIV.
 Van der Kolk, B., and Saporta, J., The Biological Response to Psychic Trauma: Mechanisms and Treatment of Intrusion and Numbing, Anxiety Research (U.K.), 1991 4, pp. 199-212, available at www.cirp.org/library/psych/vanderkolk2/. Accessed 1/10/2005
 Zweig-Frank, H., Paris, J., & Guzder, J., Psychological risk factors for dissociation and self-mutilation in female patients with borderline personality disorder, Canadian Journal of Psychiatry, 1994 Jun; 39(5): 259-64