Aggression spectrum disorders: The distinction between Borderline Personality Disorder and Psychopathy

I recently read a fascinating book chapter written by William Arsenio titled Happy Victimization: Emotion Dysregulation in The Context of Instrumental, Proactive Aggression. Early in the chapter, the author discussed how according to a study, 4-year-old children tended to predict that a bully would feel happy after pushing around some poor chump on the playground, aka happy victimization (Arsenio & Kramer, 1992). However, at age 6, children who were probed further not only predicted that the bully would feel happy after bullying, but would feel a sense of remorse as well (4-year-olds stuck to their guns). Is this the beginning stages of moral development?

Arsenio went on to describe the possible link between emotion dysregulation and this notion of happy victimization. The victimizer initially feels positive, but then recognizes the victim's negative feelings. This then elicits an involuntary positive or negative affective response depending on a whole host of factors including temperament, empathy, and parental attachment. For most of us, emotional maturity takes its natural course and empathic development occurs. However, those afflicted with borderline personality disorder and psychopathy seem to either steer off the beaten path or miss the bus completely.

Before we speak further about these two truly disturbing personality disorders, an important distinction should be made between two subtypes of aggression mentioned in the reading. 1) Reactive aggression = "hot headed" impulsive angry reaction (ex. I'll punch you in the face because you really pissed me off). 2) Proactive aggression = "cold blooded" aggression used instrumentally to reach some desirable end (ex. I'll punch you in the face because I want your lunch money).

As I read on, I couldn't help but associate the two very different subtypes of aggression with the aforementioned personality disorders. Were adults who displayed frequent and high levels of reactive aggression more prone to being identified as borderline? Similarly, were those displaying frequent and high levels of proactive aggression more prone to being identified as psychopathic? It seemed to fit all too well to be disregarded, but of course that's not all to the story. To clarify where I'm going with this, characterizations of the personality disorders and some solid evidence are in order.

Borderline personality disorder
1. Prolonged disturbance of personality function in a person characterized by depth and variability of moods.The disorder typically involves unusual levels of instability in mood; black and white thinking, or splitting; chaotic and unstable interpersonal relationships, self-image, identity, and behavior; as well as a disturbance in the individual's sense of self.
2. over-active amygdala (i.e. overly responsive to emotion-related stimuli) (Donegan et al., 2003)
3. insecure attachment (i.e. history of verbally/physically abusive parent) (Aaronson et al., 2006)
4. ability to empathize (Fertuck et al., 2009) = intact mirror neuron system?

Psychopathy
1. An abnormal lack of empathy combined with strongly amoral conduct, masked by an ability to appear outwardly normal. They can use charisma, manipulation, and intimidation to control others and to satisfy their own need.
2. under-active amygdala (i.e. unresponsive to emotion-related stimuli) (Blair, 2008)
3. insecure attachment (i.e. history of verbally/physically abusive parent) (Saltaris, 2002)
4. inability to empathize = dysfunctional mirror neuron system? (Fekteau et al., 2008)

My speculative model in sum:

Borderline personality disorder = insecure attachment + overactive amygdala response + functional mirror neuron system => high reactive/impulsive aggression

Psychopathy = insecure attachment + underactive amygdala + dysfunctional mirror neuron system => high proactive/unemotional + reactive/impulsive aggression

Psychopaths = happy victimizers into adulthood?

References:

Aaronson CJ, Bender DS, Skodol AE, & Gunderson JG (2006). Comparison of attachment styles in borderline personality disorder and obsessive-compulsive personality disorder. The Psychiatric quarterly, 77 (1), 69-80 PMID: 16397756

Arsenio, W. F. (2006). Happy Victimization: Emotion Dysregulation in The Context of Instrumental, Proactive Aggression. Snyder, Douglas K. (Ed); Simpson, Jeffry (Ed); Hughes, Jan N. (Ed). (2006). Emotion regulation in couples and families: Pathways to dysfunction and health. (pp. 101-121). Washington, DC, US: American Psychological Association

Blair, R. (2008). Review. The amygdala and ventromedial prefrontal cortex: functional contributions and dysfunction in psychopathy Philosophical Transactions of the Royal Society B: Biological Sciences, 363 (1503), 2557-2565 DOI: 10.1098/rstb.2008.0027

FECTEAU, S., PASCUALLEONE, A., & THEORET, H. (2008). Psychopathy and the mirror neuron system: Preliminary findings from a non-psychiatric sample Psychiatry Research, 160 (2), 137-144 DOI: 10.1016/j.psychres.2007.08.022

Fertuck EA, Jekal A, Song I, Wyman B, Morris MC, Wilson ST, Brodsky BS, & Stanley B (2009). Enhanced 'Reading the Mind in the Eyes' in borderline personality disorder compared to healthy controls. Psychological medicine, 39 (12), 1979-88 PMID: 19460187

Saltaris, C. (2002). Psychopathy in juvenile offenders Can temperament and attachment be considered as robust developmental precursors? Clinical Psychology Review, 22 (5), 729-752 DOI: 10.1016/S0272-7358(01)00122-2