The notion that cutting or burning oneself could provide relief from emotional distress¹ is difficult to understand for most people, but it is an experience reported commonly among people who compulsively（强制地，强迫地） hurt themselves. Individuals with borderline personality disorder²（边缘型人格障碍） experience intense emotions and often show a deficiency（缺陷，缺点） of emotion regulation skills. This group of people also displays high prevalence rates of self-injurious behavior, which may help them to reduce negative emotional states.

Niedtfeld and colleagues studied the effects of emotional stimuli³ and a thermal⁴ stimulus⁵ in people either with or without borderline personality disorder. They conducted an imaging study using picture stimuli to induce negative, positive, or neutral affect and thermal stimuli to induce heat pain or warmth perception. The painful heat stimuli were administered at an individually-set temperature threshold（门槛，极限） for each subject.

In patients with borderline personality disorder, they found evidence of heightened activation⁶ of limbic（边的） circuitry in response to pictures evocative（唤起的） of positive and negative emotions, consistent with their reported emotion regulation problems. Amygdala（扁桃腺，杏仁核） activation also correlated with self-reported deficits⁷ in emotion regulation. However, the thermal stimuli inhibited⁹ the activation of the amygdala in these patients and also in healthy controls, presumably suppressing emotional reactivity.

Dr. John Krystal, Editor of Biological Psychiatry¹⁰, commented, "These data are consistent with the hypothesis that physically¹¹ painful stimuli provide some relief from emotional distress for some patients with borderline personality disorder because they paradoxically（自相矛盾地） inhibit⁸ brain regions involved in emotion. This process may help them to compensate¹² for deficient¹³ emotional regulation mechanisms¹⁴."

The authors note that these results are in line with（一致，符合） previous findings on emotional hyperactivity in borderline personality disorder and suggest that these individuals process pain stimuli differently depending on their arousal status.