Self-Injury

First, what is it?

Self-injury (SI) or self-harm (SH) is deliberate injury inflicted by a person upon
his or her own body without suicidal intent. Some scholars
use more technical definitions related to specific aspects of this behavior.
These acts may be aimed at relieving otherwise unbearable emotions, sensations of
unreality and numbness. It is listed in the DSM-IV-TR
as a symptom of borderline
personality disorder and is sometimes associated with mental
illness, a history of trauma and abuse, eating disorders, or
mental traits such as low self-esteem or perfectionism.
There is a positive statistical correlation between self-injury and emotional abuse.[1][2]
Non-fatal self-harm is common in young people worldwide[3] and due to this
prevailance the term self-harm is increasingly used to denote any non-fatal acts
of deliberate self-harm, irrespective of the intention.[4]

-Self-Injury, Wikipedia

By definition, then, a person who self-injures is not immediately suicidal, but it is frequent among severly depressed teens.

What do they do?

The injuries inflicted are only as varied and creative as the injurers themselves. However, common methods include: hitting, scratching, choking by constriction of airway, biting one's own body, picking at and re-opening old wounds, hair pulling, stabbing with wire, pins, paper clips, and other sharp objects, burning (such as cigarette burns), ingesting chemicals or batteries, self-poisoning (OD'ing without the intent of dying on something like pills or alcohol), and self-starvation.

Other activities (such as alcolholism and bulimia) could technically be listed as well, as they bring great harm, but the term SI or SH is generally used for cutting, bruising, scratching behaviors and the like.

Who does it?

Since many self-injurers conceal their injuries, it is impossible to get a solid, concrete numbers. Based on hospital records, psychiatric samples, and general population surveys, it appears that more women self-injure than men, and it is more frequent in younger people. It is estimated in the UK that between 1 in 12 and 1 in 15 people aged 11-25 self-injure. In the US, a study of undergraduates revealed that 9.8% had purposely cut or burned themselves in the past. When the definition of SI was expanded to include head-banging, scratching, and hitting oneself, the numbers rose to 32%.

And lastly, why would anyone ever do this?

This is the big one. I have known many teens (including myself) who have or do self-injure(d), mostly cutting or scratching. Again, the motives are unique to each individual, but some reasons include (bolded are the ones I have seen as more common):
1. Self-injury can temporarily relieve intense feelings, pressure or anxiety.
2. Self-injury may provide a sense of being real, being alive – of feeling something, even pain. It eases the emptiness many feel.
3. Injuring oneself is a way to externalize emotional internal pain – to feel pain on the outside instead of the inside.
4. Self-injury is a way to control and manage pain – unlike the pain experienced through physical or sexual abuse.
5. Self-injury is a way to break emotional numbness (the self-anesthesia that allows someone to cut without feeling the same sense of pain).
6. Self-abuse is self-soothing behavior for someone who does not have other means to calm intense emotions.
7. Self-injury (especially cutting) can leave traces of blood and wounds that may act as a visual form of calming.
8. Self-loathing – some self-injurers are punishing themselves for having strong feelings (which they were/are usually not allowed to express), or for a sense that somehow they are bad and undeserving (an outgrowth of abuse and a belief that it was deserved).
9. Self-battery is often inflicted due to anger towards the person's own actions, such as losing a job or failing a test.
10. Self-injury followed by tending to wounds is a way to express self-care, to be self-nurturing, for someone who never learned how to do that in a more direct way.
11. For some harming oneself can be a way to draw attention to the need for help, to ask for assistance in an indirect way, often because they know no other way or are scared to ask for help. Those with chronic, repetitive self injury do not want attention and hide their scars carefully.
12. Sometimes self-injury is an attempt to affect others – to manipulate them, make them feel guilty or bad, make them care, or make them go away, but this is not nearly as frequent as stereotypes suggest.
13. Intense pain can lead to the release of endorphins and therefore become a means of seeking pleasure.

Cutting and other forms of SI are very addictive because it can be used as a immediate reliever of stress.

SI seems so foreign and stupid as I type this, but the chaotic emotions I felt are much too complicated to put into words. Many don't seem to understand the choice, saying that there are so many other options. In reality, SI/cutting is a "secret shame," and oftentimes, due to the circumstances involved, the person probably feels very alone and there may be few available outlets for help. And, of course, s/he must want to stop too- and many don't, at least not for awhile. Injuries are usually well-hidden.

This is a broad topic in which a lot remains to be said. While this is slightly off the topic of this blog, I believe this is a pertinent issuse which needs to be addressed. I will probably write more about this in the future, possibly focusing on quitting methods and what to do if someone you know self-injures, topics not covered here. I hope this post provides a good overview and helps to raise awareness about this understated issue.