Borderline personality disorder not linked to abnormal neural processing of facial expressions, study finds

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A neuroimaging study of young people with borderline personality disorder show that brain activity of these individuals when processing facial expressions does not differ from that of healthy individuals. The only difference was lower heart rate variability compared to healthy participants. The paper was published in Borderline Personality Disorder and Emotion Dysregulation.

Borderline personality disorder is a mental health condition characterized by intense emotional instability, impulsive behaviors, and unstable relationships. Individuals with borderline personality disorder experience rapid mood swings, have an intense fear of abandonment, and a distorted sense of self. They may engage in risky behaviors, have difficulty managing anger, and struggle with feelings of emptiness or loneliness. People with this disorder may also experience dissociation, a feeling of detachment from themselves or reality, particularly when they are under stress.

One of the hallmark features of borderline personality disorder is the dysregulation of emotions. Human faces are potent emotional stimuli, and researchers frequently use images of faces to study emotion processing. Results from these studies suggest that individuals with borderline personality disorder often struggle to interpret emotions on human faces accurately. This inability can lead to maladaptive behaviors and challenges in interpersonal relationships that are common in these individuals.

Study author Monika Radimecká and her colleagues note that prior research on individuals with borderline personality disorder identified distinct brain activation patterns when viewing human faces, different from those observed in healthy individuals. Specifically, previous studies found increased activity in the amygdala region of the brain. The study team aimed to confirm these findings.

The study included 30 patients with borderline personality disorder and 30 healthy participants, with only one male in each group. The average age of participants was about 24 years, and 90% of the patients also met criteria for other psychiatric disorders, such as depression, anxiety, posttraumatic stress disorder, and substance use disorder.

Participants completed assessments of borderline personality disorder symptoms (Borderline Symptom List), emotional dysregulation (Difficulties in Emotion Regulation Scale Short Form), rejection sensitivity (Rejection Sensitivity RS-Adult questionnaire), dissociation (Multiscale Dissociation Inventory), and childhood trauma (Childhood Trauma Questionnaire). After these assessments, they underwent functional magnetic resonance imaging while viewing pictures of human faces expressing various emotions. Participants also completed tasks to assess their emotion regulation abilities (the Neurofeedback task) and rejection sensitivity (the Cyberball task).

The results confirmed that participants with borderline personality disorder exhibited more symptoms of the disorder, poorer emotional regulation, greater sensitivity to rejection, and higher dissociation scores than healthy participants. However, no differences were observed in brain activity when viewing emotionally expressive faces, either when considering the entire brain or specific brain regions.

The study authors noted that participants with borderline personality disorder displayed lower heart rate variability when viewing emotional faces compared to healthy participants, though this finding was not linked to any brain activity.

“We did not find any differences between patients and healthy controls in brain activity, neither in amygdala, specifically. Further, there were no differences in amygdala habituation during the task between the groups. Although heightened amygdala activity is a frequently reported result, it seems that its connection to facial emotion processing is not straightforward, and future studies should explore its activity during specific emotional valence rather than multiple emotions. The results showed lower HRV [heart rate variability] in patients with BPD [borderline personality disorder] than in healthy controls, but HRV was not associated with BPD symptoms,” the study authors concluded.

The study contributes to the scientific understanding of the specificities of neural functioning of individuals with borderline personality disorder. However, it should be noted that the study was done on a relatively small sample of participants and it used static pictures of faces to study brain activity. Brain activity when processing emotional expressions in real life situations might not be the same.

The paper, “Facial emotion processing in patients with borderline personality disorder as compared with healthy controls: an fMRI and ECG study,” was authored by Monika Radimecká, Adéla Látalová, Martin Lamoš, Martin Jáni, Patrik Bartys, Alena Damborská, Pavel Theiner and Pavla Linhartová.