Dissociative disorders are characterised by the disruption and discontinuity in the normal integration of consciousness, memory, identity, emotion, perception, body representation, motor control and behaviour. In depersonalisation/derealisation disorder, the person’s perception of the self and surroundings is altered and they may feel detached from their body or may perceive the world as being unreal. Dissociative amnesia is defined by inability to recall important personal experiences of a traumatic or highly stressful nature. The person with dissociative identity disorder (DID) has two or
more distinct personalities, each with unique memories, behaviour patterns and relationships, whereas in subclinical DID the personality states intrude on the person’s thoughts, feelings and actions, but are not developed enough to take full control of the individual. Dissociative disorders are related to childhood abuse, neglect, insecure attachment to the primary caregiver, and exposure to traumatic and stressful events. The aetiology of dissociative disorders continues to be debated, though over time, given the increased data available on familial and institutional child abuse, allied with intriguing neuro-physiological findings, most experts see trauma as a major factor. The trauma model suggests that dissociation becomes a reflex coping strategy when the options of fighting or fleeing are not possible, as is frequently the case in young children, living with
inescapable repetitive trauma. The fantasy model suggests that fantasy-prone and suggestible individuals, often with genuine histories of abuse, have poor sleep and this combination of factors results in two false beliefs — first, in ‘recovered’ memories of (more) childhood abuse, and second, that they have a dissociative disorder, when in reality the symptoms and stories of dissociation and trauma are borrowed from the media or other people. The fantasy model has been demonstrated to lack robust empirical support. It is not uncommon for people with histories of a trauma to experience an extended period of time in which they cannot recall it; that all types of memory are open to distortion and recovered memories of trauma are found to be as accurate as continuous memories of trauma. Furthermore, differences in brain activity can be witnessed between alters, yet no differences are seen in people role-playing DID.
In the safe, supportive context of therapy, patients are encouraged to learn new strategies for coping with emotions, so as to gain better control over tendencies to rely on dissociation.
The common feature of somatic symptom and related disorders is the excessive focus on physical symptoms. The nature of the concern, however, varies by disorder. Somatic symptom disorder is defined by excessive thought, distress and behaviour related to somatic symptoms or health concerns. Illness anxiety disorder is defined by fears of a serious disease when no more than mild somatic symptoms are present. Conversion disorder is characterised by sensory and motor dysfunctions that are incompatible with recognised neurological or medical conditions. Somatic symptom and related disorders may arise suddenly in stressful situations. Factitious disorder can be distinguished from the other somatic symptom disorders as the person compulsively seeks unnecessary medical attention, not because they believe they are unwell, but in a conscious or subconscious attempt to garner care, concern and support from medical staff.
A growing body of research confirms that adverse experiences in childhood are closely linked to a range of illnesses and medical conditions, including those associated with somatic symptom and conversion disorder. Neurobiological models suggest that some people may have a propensity towards hyperactivity in those regions of the brain involved in evaluating the unpleasantness of somatic sensations, including the anterior cingulate and the anterior insula. Cognitive–behavioural models focus on attention to and interpretation of somatic symptoms as a way of understanding why some people experience such intense anxiety about their health. Psychodynamic theories of conversion disorder have focused on the idea that psychological stress following a traumatic or stressful experience converts to a physical impairment, yet most people are unaware of the subconscious motivation for their symptoms. Cognitive–behavioural therapy is the most evidenced-based approach for reducing the physical symptoms of somatic symptom and conversion disorder, as well as reducing anxiety in people with illness anxiety disorder.