High Index of Suspicion vs. Hyper-reactivity in Borderline Personality Disorder

One of the main themes of this blog is how researchers in psychiatry continually mix up learned or conditioned responses with disease states. These include misinterpreting fMRI findings and data derived from twin studies. I have also discussed something called Error Management Theory, which predicts that if you come from a toxic and crazy environment like someone with borderline personality disorder (BPD) does, and have to learn how to react to it, it is in your interest to have a high index of suspicion about the others around you. Somehow this has turned into emotional “hyper-reactivity” as some of sort of brain pathology or abnormality.

Now comes a study that seems to be strong evidence for my point of view. (Borrolla, B., Cavicchioli, C,., Fossati, A., and Maffei, C. “Emotional Reactivity Borderline Personality Disorder: Theoretical Considerations based on Meta-Analytic Review of Laboratory Studies.” Journal of Personality Disorders 34[1], 64-87, 2020). 

The authors did a meta-analysis (combining the data from several studies) which addressed the question.

Variables measured in these studies included heart rate, respiratory heart sinus arrhythmia, skin conductance, cortisol (stress hormone) levels, startle response, blood pressure, and patient self report.

Their conclusion: the hyper-reactivity hypothesis was in general not supported. The apparent increase in reactivity in BPD could instead be attributable to their tendency to evaluate emotional  stimuli more negatively than controls. Exactly what error management theory would predict!

The study authors go on to say that amygada functioning (basically fight/flight/freeze reactions) concerns “several processes that go beyond emotional arousal (salience and novelty detection, reward learning, memory, attention modulation, decision making…” (p. 79).

Exactly. And Amen.

Borderline Personality Disorder: Why They Don't “Get Used to It.”

At the annual meeting of the American Psychiatric Association in New York this year, I learned about a new finding from one study with patients who exhibit borderline personality disorder (BPD). The same finding also applied, although to a lesser degree, to those with avoidant personality disorder (AVD), which is pretty much identical to the diagnosis of Social Phobia.  I suspect that the reasons for the similar findings may be different for the two disorders.

The finding involved a part of the brain called the Amygdala. This little doohickey is central to a lot of brain functions, but in particular, it is the center for the body’s “fight or flight” response. I always though it fascinating  that the amygdala also has specific cells which respond only to one’s own mother (or other primary female attachment figure) and nothing and nobody else, and other specific cells which respond only to one’s father (or other primary male attachment figure). 

Although one cannot prove such things, this fact suggests to me that primary attachment figures may be the most potent of all of the environmental triggers to fear-based flight or fight reactions. They are certainly more powerful that a therapist can ever be for doing so, for instance.

The finding may relate to one of the primary symptoms of BPD, which goes by a variety of names. In the actual DSM criteria, it is described as “affective instability, or marked reactivity of mood (e.g., intense episodic dysphoria, irritability, or anxiety usually lasting a few hours and only rarely more than a few days.)” It is also called high reactivity, and lay people often label it hypersensistivity. In psychological tests, it is called neuroticism. Clearly, amygdala activation is intrinsic to this phenomenon.

Therapists have a tendency to think that patients with BPD over-react because they misperceive the behavior of others as being emotional slights, when the behavior is not at all meant as such. In fact, these therapists do not even know to what exactly the patient may be reacting to, or alternatively, that sometimes patients with BPD feign such reactions in order to provoke a specific response in others in order to recruit them to be enablers of the patients’ spoiler role.

For example, one patient would go ballistic if anyone ever even implied that her mother might have been a loving parent. Of course, if one knew all the horrible things her mother had done to her, one could easily see why she would find such a comment annoying - to say the least!

The study I am discussing here is by Harold Koenigsberg and others (Journal of the American Psychiatric Association 171:82-90, January 2014). Study participants were asked to look at a series of pictures with either highly negative or neutral content, and the activation of the amygdala and another region of the brain called the dorsal anterior cingulate was measured using a specific type of brain scan. The subjects also subjectively rated their emotional responses to the pictures. 

Exposure to these pictures and these measurements were then repeated. Repeated only once, I’m afraid. The study would have been a lot more powerful if they had repeated the exposure several times.

The changes in emotional arousal and brain activation after a repeat viewing of the negative images was small but signficantly different between patients with BPD or AVD and the "normal" control subjects.  

The brains of the controls seemed to habituate, while those of the patients with BPD did not.  Habituation means that the controls got used to or became accustomed to the awful pictures, and their arousal levels decreased from what it had been after the initial viewing.

If anything, the emotional arousal of patients with BPD actually increased with the repeat viewing.

This finding, if it can be replicated, might seem to indicate that the brains of those with BPD are abnormal in this regard. However, as I have ranted in the past, a difference is not automatically indicative of an abnormality. In fact, it may be a conditioned response that is highly adaptive in particular environments.

In the case of patients with BPD in particular, they invariable grow up in chaotic family environments in which “getting used” to the chaos and not reacting to it when one needs to could be hazaradous to their and their family’s health, as described in my post on Error Management Theory.  If the chaos continues, such individuals need to pay even more attention to it, not less. 

This new research finding fits my ideas about that to a tee.

Neural Plasticity and Error Management Theory

One of the ongoing themes of this blog is the nonsensical practice of some researchers in psychiatry of routinely labeling differences seen on brain scans between various diagnostic groups and control subjects as abnormalities. 

Just because there is more blood flow to one area of the brain during the performance of certain tasks or a difference in size between various subsections of the more primitive part of the brain, the limbic system, in a group of people who show similar behaviors and symptoms does not automatically mean that this demonstrates a disease process.

We know now that the neural structure of the brain is extremely plastic, and many of these differences merely reflect the fact that people who have certain habitual behavior patterns routinely show these differences. Disease processes can also certainly account for differences, but just the mere presence of a difference does not tell us which of the two possibilities - abnormality or normal difference – is the accurate explanation for the finding

As I pointed out on my post Neural Plasticity on March 14, 2010, after just three months of a vigorous exercise program in one study, the size of a brain structure called the hippocampus increased an average of 16% in normal people.

So how do we determine whether a difference is or is not an abnormality? Well, one line of evidence that may help tip the balance of evidence and help us to decide is the use of something called Error Management Theory (EM). This is an extensive theory of perception and cognitive biases that was created by David Buss and Martie Haselton (Haselton, M. G., & Buss, D. M.  Error management theory: A new perspective on biases in cross-sex mind reading. Journal of Personality and Social Psychology, 2000; 78:81-91) and expanded upon in another article (Haselton MG, Nettle D. The paranoid optimist: an integrative evolutionary model of cognitive biases. Personality and Social Psychology Review. 2006; 10(1):47-66).

Martie Haselton, Ph.D.

The human species is highly adaptive to its environment, particularly its social environment. The survival of we human beings, and our ability to live long enough to have children and pass along our genes, depends on how well we can read and react to that environment. In particular, we need the ability to read the motives of other members of our species to determine whether or not we may be being deceived or endangered by them.

It making a determination about whether the environment is dangerous or friendly, it is often true that it is far better for long-term survival and procreation to err on one side or the other in making this judgment. A friendly situation might be misinterpreted as a dangerous one while a dangerous situation might be misinterpreted as a friendly one. 

Depending on the environment, a false negative or a false positive interpretation might prove fatal; hence, it is often best to err consistently in one of these directions.

The best illustration of this is the "unidentified animal in the woods" problem. If you are walking in a forrest and mistake a raccoon for a bear and run away, all you have lost is some needless expenditure of energy. If, on the other hand, you mistake a bear for a raccoon and don’t run away, you are dead.  So all other things being equal, if you cannot identify the animal for sure, it is always better to run.

So what does this have to do with neural plasticity? To illustrate, allow me return to the issue of my favorite “diagnostic” group, the patients who exhibit traits of borderline personality disorder (BPD). These folks can be extremely reactive to stress in the social environment. They tend to get more agitated that the average person in response to any perceived slight, and it takes them much longer to calm down. Their behavioral reactions tend to be sort of "shoot first and ask questions later, if at all."

It is also true that some but not all fMRI studies show that, on average, patients with BPD have slightly reduced volumes compared with normal controls in several brain areas including the frontal lobe, bilateral hippocampus, left orbito-frontal cortex, right anterior cingulated cortex, and right parietal cortex.  

Another recent study (Ruocco et. al., Biol Psychiatry, 2013;73:153–160) showed that BPD patients demonstrated greater activation within the insula and posterior cingulate cortex. Conversely, they showed less activation than control subjects in a network of regions that extended from the amygdala to the subgenual anterior cingulate and dorsolateral prefrontal cortex. 

Abnormalities, or just differences?

Well, these brain areas are involved in the body’s threat assessment as well as fight, flight or freeze reactions in response to potentially dangerous environmental situations.  Panic attacks and rage attacks, common in these patients, are also created in some of these brain areas.

Many studies have shown that the childhood family environment of patients who go on to develop BPD is often highly chaotic and unpredictable. Therefore, “normal” inhibition of fear and rage responses might be extremely maladaptive. The size and activity level of the amygdala and other limbic system structures might be gradually shaped through ongoing environmental interaction, so that on average they look different than "normal" control subjects.

Voila. If prospective (studies in which babies are followed for many years) studies showed this hypothesis to be true, this would be potential evidence that these differences are normal differences, not abnormalities. 

The borderline trait of hyper-reactivity often becomes maladaptive in non-family adult social situations because most other people do not react like the family members that produce offspring that show borderline traits.

Unfortunately, for reasons discussed elsewhere in this blog, patients with BPD usually look for people to hang out with that do in fact act like their family members, and, if the others do not act like that, often go out of their way to try to provoke them to react in these ways.

Error management theory may also explain something that psychologists call the fundamental attribution error. When observing the behavior of strangers, we are all more likely to attribute their behavior to the person’s underlying dispositions to a greater extent than is logically warranted. We all err on the side of thinking that their behavior is due to their innate tendencies rather than it being a reasonable reaction to the particular environmental situation in which they find themselves. This social judgment, wrong though it often is, helps us to avoid connecting with poor social partners.

So, is it better to be paranoid or to be optimistic? It all depends on our experiences over a lifetime. Due to natural selection, the truth of any particular judgment is far less important to us than its potential effects on our survival and reproductive success.