Biology+of+ASPD

= = toc The cause behind ASPD has been disputed throughout the years. Through Lombardo's 'criminaloid' theory, nature vs. nurture, and new scientific advances, there has been breakthroughs in understanding this interesting disorder. Though Lombardo's theory was discarded almost immediately while the other arguments have adopted steadfast viewpoints. There was a constant disagreement between the "hereditarians" and "environmentalists." Hereditarians believed in nature-- that the individual with ASPD was born with a genetic predisposition or inherited the traits from his/her parents; while environmentalists believed that outside influences (parental treatment, trauma, peer interaction) was the cause behind the disorder. This ongoing argument led to the conclusion that the problem isn't one or the other, but a combination of both-- "nature plus nurture" (Green, 2005). A very interesting study is shown below:

**"Reduced Prefrontal Gray Matter Volume and Reduced Autonomic Activity in Antisocial Personality Disorder** Adrian Raine, DPhil; Todd Lencz, PhD; Susan Bihrle, PhD; Lori LaCasse, BA; Patrick Colletti, MD

**Background** Major damage to gray and white matter in the prefrontal cortex and autonomic deficits have been found toresult in pseudopsychopathic personality in patients with neurological disorders, but it is not known whether people with antisocial personality disorder (ASPD) in the community who do not have discernible brain trauma also have subtle prefrontal deficits.

**Methods** Prefrontal gray and white matter volumes were assessed using structural magnetic resonance imaging in 21 community volunteers with ASPD (ASPD group) and in 2 control groups, comprising3 4 healthy subjects (control group), 26 subjects with substance dependence (substance-dependent group), and 21 psychiatric controls. Autonomic activity (skin conductance and heart rate) was also assessed during a social stressor in which participants gave a videotaped speech on their faults.

**Results** The ASPD group showed an 11.0% reduction in prefrontal gray matter volume in the absence of ostensible brain lesions and reduced autonomic activity during the stressor. These deficits predicted group membership independent of psychosocial risk factors.

**Conclusions** To our knowledge, these findings provide the first evidence for a structural brain deficit in ASPD. This prefrontal structural deficit may underlie the low arousal, poor fear conditioning, lack of conscience, and decision-making deficits that have been found to characterize antisocial, psychopathic behavior" (Adrian, 2000).

media type="youtube" key="oaTfdKYbudk" height="315" width="420" The above video features Dr. Hare, who describes the type of experiment below.

A recent study was performed by a group of researchers to identify key happenings (of lack thereof) in brains of people with ASPD-- namely inhibitory control (resisting a strong urge to act impulsively rather than perform what is most appropriate or needed). In this experiment, there were three groups including a control. Here are the results: //"To inform this area of research, we recorded event-related brain potentials during an emotional-linguistic Go/No-Go task to examine modulation of negative emotional processing by inhibitory control in three groups: psychopathy (n = 14), ASPD (n = 16), and control (n = 15). In control offenders, inhibitory control demands (No-Go vs. Go) modulated frontal-P3 amplitude to negative emotional words, indicating appropriate prioritization of inhibition over emotional processing. In contrast, the psychopathic group showed blunted processing of negative emotional words regardless of inhibitory control demands, consistent with research on emotional deficits in psychopathy. Finally, the ASPD group demonstrated enhanced processing of negative emotion words in both Go and No-Go trials, suggesting a failure to modulate negative emotional processing when inhibitory control is required"// (Verona, 2012). In the modern vernacular, these results identified that not only was there a significant difference in inhibitory functioning, but the group with ASPD was able to understand and process negative emotion words but the inhibitory control was not there.