Tissue damage caused by exposure to ionizing radiation. Structures with rapid cell turnover (e.g., skin, stomach or intestinal lining, and bone marrow) are most susceptible. High-dose irradiation of the last two causes radiation sickness. Nausea and vomiting subside in a few hours. They are followed in intestinal cases by abdominal pain, fever, and diarrhea leading to dehydration and a fatal shocklike state, and in bone-marrow cases (two to three weeks later) by fever, weakness, hair loss, infection, and hemorrhage. In severe cases, death occurs from infection and uncontrollable bleeding. Lower radiation doses can cause cancer (notably leukemia and breast cancer), sometimes years later. Radiation exposure in early pregnancy can produce abnormalities in the embryo, whose cells are multiplying rapidly.
Learn more about radiation injury with a free trial on Britannica.com.
Break in any body tissue due to external action (including surgery). It may be closed (blunt trauma) or open (penetrating trauma). Blood vessels, nerves, muscles, bones, joints, and internal organs may be damaged. A closed wound can be caused by impact, twisting, bending, or deceleration (as in a car crash). It can range from a minor bruise or sprain to a skull fracture with brain damage or a spinal-cord injury with paralysis. In an open wound, foreign matter such as bacteria, dirt, and clothing fragments entering through broken skin or mucous membrane may result in infection. Other factors affecting severity include depth, surface area, degree of tearing, and structures damaged. Minor wounds need only first aid. For others, after examination and perhaps diagnostic imaging and exploratory surgery, treatment may include fluid replacement or drainage, sterilization and antibiotics, tetanus antitoxin, and repair of damaged structures. A closed wound may need to be opened or an open one sutured closed. Seealso burn, coagulation, crush injury, dislocation, scar.
Learn more about wound with a free trial on Britannica.com.
Self-injury (SI) or self-harm (SH) is deliberate injury inflicted by a person upon their own body without suicidal intent. Some scholars use more technical definitions related to specific aspects of this behaviour. These acts may be aimed at relieving otherwise unbearable emotions, sensations of unreality and numbness. The illness is listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) as a symptom of borderline personality disorder and depressive disorders. It is sometimes associated with mental illness, a history of trauma and abuse including emotional abuse, sexual abuse, eating disorders, or mental traits such as low self-esteem or perfectionism, but a statistical analysis is difficult, as many self-injurers conceal their injuries.
Self harmers are often mistaken as suicidal, but in the majority of cases this is inaccurate. Non-fatal self-harm is common in young people worldwide and due to this prevalence the term self-harm is increasingly used to denote any non-fatal acts of deliberate self-harm, irrespective of the intention.
There are a number of different treatments available for self-injurers which concentrate on either treating the underlying causes or on treating the behaviour itself. When self-injury is associated with depression, antidepressant drugs and treatments may be effective. Alternative approaches involve avoidance techniques, which focus on keeping the self-injurer occupied with other activities, or replacing the act of self-harm with safer methods that do not lead to permanent damage.
A common belief regarding self-injury is that it is an attention-seeking behaviour; however, in most cases, this is inaccurate. Many self-injurers are very self-conscious of their wounds and scars and feel guilty about their behaviour leading them to go to great lengths to conceal their behaviour from others. They may offer alternative explanations for their injuries, or conceal their scars with clothing. Self-injury in such individuals is not associated with suicidal or para-suicidal behaviour. The person who self-injures is not usually seeking to end his or her own life; it has been suggested instead that he or she is using self-injury as a coping mechanism to relieve emotional pain or discomfort. Studies of individuals with developmental disabilities (such as mental retardation) have shown self-injury being dependent on environmental factors such as obtaining attention or escape from demands. Though this is not always the case, some individuals suffer from disassociation and they harbor a desire to feel real and/or to fit in to society's rules. A common form of self-injury involves making cuts in the skin of the arms, legs, abdomen, inner thighs, etc. However, the number of self-injury methods are only limited by an individual's creativity and include, but are not limited to, compulsive skin picking (dermatillomania), hair pulling (trichotillomania), burning, stabbing, poisoning, alcohol abuse and forms of self harm related to anorexia and bulimia. The locations of self-injury are often areas of the body that are easily hidden and concealed from the detection of others. As well as defining self-harm in terms of the act of damaging one's own body, it may be more accurate to define self-harm in terms of the intent, and the emotional distress that the person is attempting to deal with. Neither the DSM-IV-TR nor the ICD-10 provide diagnostic criteria for self-injury. It is often seen as only a symptom of an underlying disorder, though many people who self-injure would like this to be addressed.
This gender discrepancy is often distorted in specific populations where rates of self-injury are inordinately high, which may have implications on the significance and interpretation of psychosocial factors other than gender. A study in 2003 found an extremely high prevalence of self-injury among 428 homeless and runaway youth (age 16 to 19) with 72% of males and 66% of females reporting a past history of self-mutilation.
There does not appear to be a difference in motivation for self-harm in adolescent males and females. For example, for both genders there is an incremental increase in deliberate self-harm associated with an increase in consumption of cigarettes, drugs and alcohol. Triggering factors such as low self-esteem and having friends and family members who self-harm are also common between both males and females. One limited study found that, among those young individuals who do self-harm, both genders are just as equally likely to use the method of skin-cutting. However, females who self-cut are more likely than males to explain their self-harm episode by saying that they had wanted to punish themselves. In New Zealand, more females are hospitalised for intentional self-harm than males. Females more commonly choose methods such as self-poisoning that generally are not fatal, but still serious enough to require hospitalisation.
Some of the causes of deliberate self-poisoning in Sri Lankan adolescents included bereavement and harsh discipline by parents. The coping mechanisms are being spread in local communities as people are surrounded by others who have previously deliberately harmed themselves or attempted suicide. One way of reducing self-harm would be to limit access to poisons; however many cases involve pesticides or yellow oleander seeds, and the reduction of access to these agents would be difficult. Great potential for the reduction of self-harm lies in education and prevention, but limited resources in the developing world make these methods challenging.
Attempts to understand self-injury fall broadly into either attempts to interpret motives, or application of psychological models.
Motives for self-injury are often personal, often do not fit into medicalised models of behaviour and may seem incomprehensible to others, as demonstrated by this example:
My motivations for self-harming were diverse, but included examining the interior of my arms for hydraulic lines. This may sound strange.
Motives for self-injury can be different. Some feel as if they are not good enough and they might not want to take it out on the person who harmed them. It's often difficult for them to open up and tell about their "secret shame". Often when the sufferer does tell somebody there is a lack of understanding or knowledge of how to help.
Assessment of motives in a medical setting is usually based on precursors to the incident, circumstances and information from the patient however the limited studies comparing professional and personal assessments show that these differ with professionals suggesting more manipulative or punitive motives.
The UK ONS study reported only two motives: "to draw attention" and "because of anger". Many people who self-injure state that it allows them to "go away" or dissociate, separating the mind from feelings that are causing anguish. This may be achieved by tricking the mind into believing the suffering felt at the time is caused by self-injury instead of the issues they were facing before: the physical pain therefore acts as a distraction from emotional pain. To complement this theory, one can consider the need to 'stop' feeling emotional pain and mental agitation. "A person may be hyper-sensitive and overwhelmed; a great many thoughts may be revolving within their mind, and they may either become triggered or could make a decision to stop the overwhelming feelings." The sexual organs may be deliberately hurt as a way to deal with unwanted feelings of sexuality, or as a means of punishing sexual organs that may be perceived as having responded in contravention to the person's wellbeing. (e.g., responses to childhood sexual abuse).
Alternatively self-injury may be a means of feeling something, even if the sensation is unpleasant and painful. Those who self-injure sometimes describe feelings of emptiness or numbness (anhedonia), and physical pain may be a relief from these feelings. "A person may be detached from himself or herself, detached from life, numb and unfeeling. They may then recognise the need to function more, or have a desire to feel real again, and a decision is made to create sensation and 'wake up'."
It is also important to note that many self-injurers report feeling very little to no pain while self-harming. Those who engage in self-injury face the contradictory reality of harming themselves whilst at the same time obtaining relief from this act. It may even be hard for some to actually initiate cutting, but they often do because they know the relief that will follow. For some self-injurers this relief is primarily psychological whilst for others this feeling of relief comes from the beta endorphins released in the brain (the same chemicals that are thought to be responsible for the "runner's high" and are similar to morphine). Endorphins are endogenous opioids that are released in response to physical injury, act as natural painkillers, and induce pleasant feelings and would act to reduce tension and emotional distress.
As a coping mechanism, self-injury can become psychologically addictive because, to the self-injurer, it works; it enables him/her to deal with intense stress in the current moment. The patterns sometimes created by it, such as specific time intervals between acts of self-injury, can also create a behavioural pattern that can result in a wanting or craving to fulfill thoughts of self-injury.
Self-injury is known to have been a regular ritual practice by cultures such as the ancient Maya civilization, in which the Maya priesthood performed auto-sacrifice by cutting and piercing their bodies in order to draw blood. It is also practiced by the sadhu or Hindu ascetic and in Christian mortification of the flesh.
In individuals with developmental disabilities, occurrence of self-injury is often demonstrated to be related to its effects on the environment, such as obtaining attention or desired materials or escaping demands. As developmentally disabled individuals often have communication or social deficits, self-injury may be their way of obtaining these things which they are otherwise unable to obtain in a socially appropriate way (such as by asking). One approach for treating self-injury thus is to teach an alternative, appropriate response which obtains the same result as the self-injury.
Generating alternative behaviours that the sufferer can engage in instead of self-injury, and shaping the use of such behaviours, is one successful behavioural method that is employed to avoid self-harm. Techniques, aimed at keeping busy, may include journaling, taking a walk, participating in sports or exercise or being around friends when the sufferer has the urge to harm themselves. The removal of objects used for self-injury from easy reach is also helpful for resisting self-injurious urges. The provision of a card that allows sufferers to make emergency contact with counselling services should the urge to self-harm arise may also help prevent the act of self-injury. Alternative and safer methods of self-harm that do not lead to permanent damage, for example the snapping of a rubber band on the wrist, may also help calm the urge to self-harm.