As its name suggests, a personality disorder is a problem rooted in personality. Unlike some other classes of psychological disorder, a personality disorder is seen as something inherent or internal in a person, rather than a result of something that has happened to them. As a result its aetiology is analysed in the same vein as that of personality: genetics, the family peer groups and random life events. Personality disorders are formally defined in the Diagnostic and Statistical Manual (DSM). The DSM-IV (APA, 2000) lists ten different types of personality disorders, which fall into three clusters: odd/eccentric, dramatic/emotional/erratic and anxious/ fearful. This typology of personality disorders has long been considered controversial and perhaps this is a direct result of the failure of the classifications to be made on an empirical basis. There is now a large weight of empirical evidence that suggests these classifications of personality are not providing valid or even useful delineations of psychological disorders. In order to analyse this evidence, two personality disorders, borderline personality disorder and paranoid personality disorder, as defined within the DSM-IV (APA, 2000), will be briefly introduced and then the evidence surveyed.
The diagnostic criteria for borderline personality disorder (BPD) are described in the DSM-IV as including unstable interpersonal relationships, an unstable self-image and an overall marked instability. One of the clearest diagnostic criteria is a fear of abandonment. This links into the BPD client's lack of a sense of self-worth. The client may also suffer from rapid mood-swings and may often be very difficult to deal with in a therapeutic situation. Like all of the personality disorder, BPD is considered very difficult to treat because the sufferer will not often realise or acknowledge that they have a problem. It is often argued, especially by those working from a cognitive behavioural perspective, that the roots of BPD lie in core beliefs obtained during childhood (Grant, 2004). Core beliefs considered 'normal' allow people to view the world and themselves in a balanced way with the requisite flexibility. A person is continually subjected to a range of both negative and positive attitudes towards the self that require balancing. In contrast, those with BPD are likely to have obtained negative messages about themselves from their parents and consequently are unable to balance the positive and negative attitudes coming from people around them. Cognitive Therapy will concentrate on helping sufferers combat these negative belief and indeed the negative beliefs that they are bound to have about the process of therapy and the therapist (Beck & Freedman, 1990).
