The Definition of a Personality Disorder

The diagnostic manual of the American Psychiatric Association (APA, 2000) captures these differences between healthy and unhealthy personalities that we have just discussed and defines a personality disorder as follows: "The essential feature of a Personality Disorder is an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the individual's culture and is manifested in at least two of the following areas: cognition, affectivity, interpersonal functioning, or impulse control (Criterion A). This enduring pattern is inflexible and pervasive across a broad range of personal and social situations (Criterion B) and leads to clinically significant distress or impairment in social, occupational, or other important areas of functioning (Criterion C). The pattern is stable and of long duration, and its onset can be traced back at least to adolescence or early adulthood (Criterion D). The pattern is not better accounted for as a manifestation or consequence of another mental disorder (Criterion E) and is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication, exposure to a toxin) or a general medical condition (e.g., head trauma) (Criterion F)…"(American Psychiatric Association, DSM-IV-TR (2000), p.686).

The Diagnostic and Statistical Manual IV-TR (APA 2000) further identifies ten specific personality disorders according to different patterns or constellations of personality traits. It also lists four core features common to the entire category of personality disorders (Criterion A). We now turn our attention to these four core features of personality disorders in order to further distinguish between healthy and unhealthy personalities.

The Four Core Features of Personality Disorders¹

The DSM-IV-TR (APA, 2000) identifies and describes ten specific diagnoses of personality disorders that represent ten specific enduring patterns or constellations of personality traits, and characteristic ways of thinking, feeling and behaving that rise to level of a disorder. However, in addition to these 10 specific patterns, the experts who put together the definition of personality disorders in DSM-IV-TR (APA, 2000) IV also identified four core features that characterize all personality disorders (Criterion A). These four core features enable us to better differentiate between a normal, healthy personality from one that is not:

1. Extreme and distorted thinking patterns
2. Problematic emotional response patterns
3. Impulse control problems
4. Significant interpersonal problems

In fact, in order to diagnose a personality disorder a person must exhibit at least two of these four core features². The interested reader may also wish to consult a very thorough and detailed discussion of these four core features discussed in Andrew Skodol's chapter in the Textbook of Personality Disorders (Oldham, Skodol and Bender, 2005).

In this section we will review each of these four core features that are common to all personality disorders. Then in the next section, we will discuss the ten specific personality disorders diagnoses as described in DSM-IV-TR (APA, 2000). As you are reading about these disorders, you may find yourself wondering if they are accurate enough; if they have been defined in a precise enough manner so as to easily distinguish between people who have personality disorders from those who do not. As mentioned, personality disorders are a variant form of normal, healthy personality so such distinctions are often difficult. If such thoughts occur to you, you are not alone. Quite a few clinicians and researchers have raised concerns about this lack of specificity and precision. It is often difficult, even for experienced clinicians to diagnose a personality disorder as a separate disorder, and distinct from other psychological disorders that occur at the same time (called co-occurring disorders). Later, we will discuss alternatives to the current DSM diagnostic systems for the personality disorders that attempt to resolve this problem of imprecision in a later section and the problem of co-occurring disorder).

Since the current diagnostic system³ for personality disorders is difficult to use for the reasons cited above, we want to caution you to refrain from trying to diagnose yourself, or someone else. The diagnostic process for personality disorders is difficult enough, even for seasoned professionals; therefore, self-diagnosis is not recommended. If you suspect a problem or interpersonal difficulty may be related to a personality disorder, we urge you to raise these concerns with a qualified mental health professional. A professional experienced with the diagnosis and treatment of personality disorders is best able to make a correct diagnosis (having done it many times before), and will be in the best position to recommend an effective treatment plan. In the later part of this article, we will review effective, state-of-the-art treatments for personality disorders.

1 It should be noted that the upcoming revision, DSM-V, proposes to truncate these four features down to two; namely, problems with a cohesive and consistent sense of self, and problems with interpersonal functioning. Regardless of the final outcome of the DSM-V nomenclature, these four features will remain very helpful in identifying and understanding personality disorders. Further information about DSM-V is available at http://www.dsm5.org/pages/default.aspx and http://en.wikipedia.org/wiki/DSM-V.

2 Ibid.

3 The current diagnostic system at the time of publication is DSM-IV-TR (APA, 2000). Changes are expected in the upcoming DSM-V. Further information about DSM-V is available at http://www.dsm5.org/pages/default.aspx and http://en.wikipedia.org/wiki/DSM-V.