Borderline personality (BP) is associated with a few different problems related to thinking. These cognitive problems often contribute to other symptoms, including relationship problems, emotional instability, and impulsive behavior. Some treatments for BP focus on addressing these problems in thinking.
Many people with BP experience paranoia as part of their disorder; they have beliefs that others mean them harm, without basis in reality. Most people with BP who have paranoia experience transient symptoms that occur under conditions of stress rather than all the time. Chronic paranoid ideation (i.e., long-standing and unchanging delusional beliefs that others plan to harm you) may be indicative of a psychotic disorder, such as schizophrenia.
People with BP also have a tendency to think in extremes, a phenomenon called “dichotomous” or “black-or-white” thinking. People with BP often struggle to see the complexity in people and situations, and are unable to recognize that things are often not either perfect or horrible, but are something in between. This can lead to "splitting," which refers to an inability to maintain a cohesive set of beliefs about oneself and others.
Because of these extreme patterns of thinking, people with borderline personality are prone to slip from one side to the opposite side in their thinking. For example, they might one day believe that their partner is the most wonderful, loving person in the world, and the next think that they are evil, hateful, and full of contempt.
Another problematic pattern of thinking that occurs in BP has less to do with the content of thoughts (i.e., what people with BP think about) but rather the process of perception. Dissociation is a common symptom of BP that involves feeling “unreal,” numb, or separate from one’s own body or psychological experiences.
Again, in most people with BP, dissociative symptoms tend to occur under conditions of stress. Some experts believe that dissociation is actually a way of coping with very intensely emotional situations by “shutting down” or separating from the experience.
How Do BP Treatments Address Problems in Thinking?
Most psychotherapies for BP include strategies for addressing the problems in thinking that are characteristic of BP. Some therapies accomplish this indirectly (i.e., by working on problems in relationships, as in Transference-Focused Psychotherapy), and some try to intervene directly with thoughts and thinking patterns.
In Schema-Focused Therapy, clients learn the origins of their ways of thinking (for example, many people with BP come from childhood environments that may promote dichotomous thinking patterns), and work with their therapist and on their own to recognize maladaptive ways of thinking and to change those patterns.
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR Fourth Edition. American Psychiatric Association: 2000.
Glaser J-P, Van Os J, Thewissen V, Myin-Germeys I. "Psychotic Reactivity in Borderline Personality Disorder." Acta Psychiatrica Scandinavica, 121(2):125-134, 2010.