Why do people self-injure?

Self-injury can be difficult to understand, as it appears to go against humans' innate desire to avoid harm. However, the reasons someone might injure themselves on purpose are often similar to the reasons people engage in other behaviours. Individuals who have self-injured often report more than one reason for their self-injury, and their reasons may change over time. The functions of self-injury can be classified into two broad categories: intrapersonal and interpersonal. Self-injury for intrapersonal reasons is more common than for interpersonal reasons (Taylor et al., 2018).

Intrapersonal functions

Intrapersonal reasons have to do with an individual's internal state, including thoughts and emotions. There are three main intrapersonal functions:

  1. Emotion regulation. The most commonly reported reason to engage in self-injury is to manage emotional experiences. This includes escaping an unwanted emotions or inducing a desired emotion. Typically, these emotions are "negative", such as anger, frustration, sadness, and loneliness, but "positive" emotions such as excitement or pride have also been reported.

  2. Thought regulationThis is closely linked to emotion regulation, as our thoughts and emotions are connected. Individuals may use self-injury to control or quieten unwanted thoughts, such as self-criticism or suicidal ideation.

  3. Self-punishment. While self-punishment appears to serve an emotion regulation purpose, self-injury for this reason is usually tied to feelings or shame or thoughts about oneself being "flawed" or "bad".

Interpersonal functions

Interpersonal functions have to do with an individual's connection with others, and include three main reasons:

  1. Communicating distress. Sometimes individuals may not know how to explain their distress to others and use self-injury as a way to communicate their feelings. 

  2. Social influence. There may be several motivations underlying self-injury as a way to influence others. An individual may engage in self-injury to keep people away from them, to demonstrate their belonging to a social group, to elicit care, or to encourage a change in behaviour.

  3. Punishment. Sometimes a person may engage in self-injury as a way to punish another person for something they have or have not done. In these instances, the self-injury is typically communicating distress and serving an emotion regulation function as well.

Other functions

The reasons people self-injure are complex and dynamic. While most reasons people give for their self-injury are captured in the above categories, some may not be as obviously related. Some other reasons can include:

  • Maintaining balance. After experiencing something positive, an individual may self-injure to maintain the balance of "good" (the positive experience) and "bad" (the self-injury).

  • Self-care. An individual may self-injure as a way to provide themselves with tangible care, such as looking after a wound.

  • Dealing with dissociation. A person experiencing dissociation may feel disconnected from their thoughts, feelings, memories, and/or sense of self. An individual may self-injure as a way to 'return to their body'.