It is not unusual for a person to be affected by the death of a loved one or a traumatic incident involving themselves. These so-called 'life events' can precipitate a range of mental health problems ranging from depression to schizophrenia, and are recognized as being important factors in the development and course of such conditions. However, stressful events may also produce a 'reaction' that prevents the individual from functioning normally, and which may require treatment in order to help the person return to their normal way of life. This entry looks at stress, adjustment and bereavement reactions and also covers the dissociative disorders.

Adjustment Reaction

Adjustment reaction refers to a broad range of symptoms that do not justify a diagnosis of stress reaction (see below), depression, anxiety and so forth, but represent abnormal behaviour following psychological stress. Symptoms may include those of mild anxiety or depression, difficulty coping with changes, and in some cases extend to aggressive or reckless actions that are clearly out of character. Adjustment disorder can be diagnosed if an adjustment reaction occurs within a month of a stressful event and lasts for less than six months, and is not better explained by another diagnosis. Adjustment reactions are best treated with talking therapies, which aim to help the individual cope better with stressful changes.

Stress Reaction

The term stress reaction is very specific, referring only to the after-effects of stresses that are so extreme that they would be considered traumatic by almost any ordinary individual. Such stresses include natural disasters, dangerous accidents, armed combat and violent assault. Reactions to stress were common during the First World War, when they were known as 'shell shock'. Two forms of stress reaction are now thought of as existing: acute stress reaction and post-traumatic stress disorder.

An acute stress reaction takes place directly after the event occurs, with the individual rapidly becoming dazed and confused. The person becomes unable to respond to external stimuli and may become extremely unresponsive or agitated. The individual may even enter a dissociative stupor (see below), and may develop amnesia for the event. These symptoms usually resolve in a few hours, and will not persevere beyond a few days' duration even if the cause of the stress is still present.

In contrast, post-traumatic stress disorder typically develops within six months of the original event and may persist for years. Symptoms include repeated flashbacks and hallucinations of the traumatic event, amnesia for the event, insomnia, angry outbursts, numbed feelings, wariness of surroundings, difficulty concentrating and withdrawal from social situations. Reminders of the event will cause the individual distress, and they may at times enter a dissociative state (see below) in which they re-experience the event while fully conscious.

PTSD is treated with a combination of anti-depressants, which treat both the conditions and the depression often associated with it, and psychotherapy. While debriefing following the traumatic event is unhelpful and may even cause harm, psychotherapy aimed at correcting errors in the individual's thinking (cognitive behavioural therapy) and at re-exposing the individual to traumatic memories while in a safe environment (eye movement desensitization and reprocessing) have been shown to be useful.

Dissociative Disorders

Dissociation is a rare condition whereby an individual's mind becomes disrupted and thoughts, emotions, memories, sense of identity and behaviour fall beyond normal conscious control. This can only occur following some form of disturbing event, and can only be considered as a diagnosis when all other possible causes, both physical and psychiatric, have been ruled out. It is a well-known fact that many diagnoses of dissociative disorder are later replaced with diagnoses of epilepsy, mood disorders, psychosis, or even intentional malingering. Some dissociative states include:

• Dissociative amnesia – inexplicable loss of memory for an event.

• Dissociative stupor – inexplicable severe unresponsiveness, lack of movement and muteness.

• Dissociative fugue – sudden adoption of a new purpose leading to travel, sometimes with amnesia for real identity.

• Dissociative anaesthesia – inexplicable loss of sensation or vision.

• Dissociative motor disturbance – inexplicable loss of muscle use.

• Dissociative convulsions – inexplicable 'pseudoseizures' that lack the characteristics of epileptic seizures.

• Ganser's sydrome – a disorder in which behaviour and speech is persistently nonsensical, but betrays some understanding of the situation.

• Multiple personality disorder – a rare and disputed diagnosis that describes the existence of several personalities in the same mind.

It is worth pointing out again that such disorders are rare, and that alternative causes should always be considered. However, it would seem that a certain degree of dissociation may occur in normal people, leading to depersonalised and derealised experiences. Depersonalisation describes a sort of 'double take' where a person's own body seems unfamiliar or strange. Derealisation refers to the same feeling directed outwards, where reality somehow seems unreal or manufactured. These experiences can occur from time to time as part of the mind's normal functioning, but can also result from stress, mental illness, epilepsy or substance misuse.

Bereavement Reaction

Bereavement reaction refers to a special form of reaction caused by the loss of a loved person or something else that a person holds dearly. This includes such things as deaths of family and friends, deaths of dearly-loved pets, diagnosis with a chronic or terminal illness, and divorce or the ending of a long-term relationship. Bereavement reaction is recognised as having a series of stages, as defined by psychiatrist Colin Parkes:

• Alarm – a state of stress including increased blood pressure and heart rate.

• Numbness – a state of self-protective emotional disconnection.

• Pining – preoccupation with the deceased, including feelings of anxiety and grief.

• Despair – low mood characterised by loss of appetite, insomnia, poor concentration and memory, and a lack of pleasure from activities.

• Recovery – an acceptance of the loss, decreased grieving and return to normal functioning.

The duration of a bereavement reaction varies greatly, though reactions lasting more than six months are uncommon and point to the more severe diagnosis of adjustment disorder. Also, severe depressive symptoms may develop alongside those of a bereavement reaction and care should be taken not to mistake these for part of the normal process of grieving.

The following entries may be helpful for those coping with a bereavement:

• How Best to Cope with Bereavement
• Dealing with Other People's Concern Over Your Own Bereavement
• Outliving Your Child