Borderline Personality Disorder Brain Anatomy

A study recently appearing in the May 2007 issue of Journal of Psychiatry and Neuroscience reviews what we know about brain structure of BPD patients.

What Is Borderline Personality Disorder?

BPD is a type of psychological personality disorder that interferes with an individual’s ability to regulate emotion. It affects as many as 1% to 2% of the general population.
The characteristic emotional instability of BPD results in dramatic and abrupt shifts in mood, impulsivity, poor self-image and tumultuous interpersonal relationships. Highly sensitive to rejection, those with BPD fear abandonment to such an extreme that it often results in frantic efforts to avoid being left alone, such as suicide threats and attempts (APA 2000). Nearly all BPD patients have experienced thoughts of suicide while nearly 10% commit suicide by adulthood (Skodol 2002).

The Brain and BPD

The few studies that have examined the Borderline brain have found differences in the volume and activity in brain structures related to emotion and impulsivity between individuals who have BPD and those who do not.

This study’s objective was to examine existing research on the neurological differences between individuals with and without BPD as well as the genetics that may play a role in development of this disorder.
This Suite101 summary focuses on the neuroanatomical differences that were found. For physiological differences, see Suite101 article Metabolism in the BPD Brain.

Study Methods

Using databases of academic articles, the investigators looked for relevant research published between 1980 and 2006 and found 49 journal articles describing original research about the brain and/or genetics of BPD patients.

BPD Research Findings

The use of neuroimaging in the study of BPD dates back only a few years. Overall, BPD has been linked to the amygdala and limbic systems of the brain, the centers that control emotion and, particularly, rage, fear and impulsive automatic reactions.

Studies have shown that the hippocampus and amygdala may be as much as 16% smaller in people with BPD and have suggested that experiences of trauma may lead to these neuroanatomical changes.
BPD Biological Abnormalities
Immature Coordination of Neural Networks
Working from the hypothesis that people with BPD have impaired maturation of higher-order consciousness, research suggests that abnormalities may indicate a general failure of coordination among networks of the brain. BPD patients were found to exhibit neural response patterns of people younger than themselves, perhaps indicating a failure of maturation and development of sense of self.
Abnormalities in Limbic System
MRI studies of those with BPD show abnormalities in limbic structures, particularly areas involved in negative affect (experience of feeling emotion).
Abnormalities Related to Impulsivity
Patients with BPD or APD show reduced blood flow in the right lateral temporal cortex and the right prefrontal cortex. These areas of the brain have been linked to impulsivity.
Serotonin Transporter Gene 5-HTT
Research has strongly implicated the serotonin transporter gene 5-HTT in development of BPD. Shorter alleles (pair of genes) have been associated with lower levels of serotonin and greater impulsive aggression.

Study Conclusions

Imaging technology has shown that brain structures with reduced volume in BPD patients may show hypermetabolism. Perhaps some of the lost volume in these structures (such as the amygdala) may be due to loss of inhibitory neurons; lost inhibition leading to the impulsive behavior and overly negative interpretation of others. Perhaps different developmental abnormalities lead to different clinical manifestations of BPD.

http://www.suite101.com/content/anatomy-of-the-bpd-brain-a33442