Lecture psychiatric disorders 11: neurobiology of Anti-Social Personality Disorder (ASPD) Flashcards
What is antisocial behavior?
Behavior that lacks consideration for others and that may cause damage to society
When is a patient diagnosed with Antisocial Personality Disorder (ASPD)?
A patient is diagnosed with ASPD when their antisocial behavior becomes pathological, where they consistently show no regard for right and wrong and ignore the rights and feelings of others.
Is psychopathy the same as Antisocial Personality Disorder?
No, psychopathy is a subset of ASPD. Characteristics of a psychopath differ from the characteristics of other types of ASPD.
What is Conduct Disorder (CD)?
Childhood antisocial disorder
What are characteristics of someone with Antisocial Personality Disorder (ASPD)?
- Apparant lack of remorse
- Persistent lying or stealing
- Cruelty to animals
- Recurring difficulties with the law
- Promiscuity / Poor or abusive relationships
- Aggressive, often violent behavior; prone to getting involved in fights
- Inability to tolerate boredom
- Lack access to own feelings and emotions
- Not good at detecting emotions (especially fear) in others
- Reduced empathy
- Severe disruption in moral behavior
What are characteristics of a psychopath?
- Callousness, manipulativeness, glibness and superficial charm
- Often (highly) intelligent
- Grandiose sense of self-worth
- Faking normal emotions: appearance of normalcy and mask of sanity
- Seemingly charming
- Often seems to function normal in society
What makes Antisocial Personality Disorder (ASPD) different from a psychopath?
In ASPD, there’s more pronounced poor behavioral controls, like the inadequate control of anger and temper. They’re often more rude, aggressive, abusive and show angry behavior, compared to a psychopath.
In the first study discussed in the lecture, two things were studied. The first being whether there was any damage to white or grey matter in patients with ASPD. What was the other?
Measuring autonomic nervous system (ANS) functioning. It was already known that ASPD patients showed less emotion, so they wanted to see how the ANS would react to certain stressors by measuring heart rate and skin conductance.
What were the results of the first study when they looked at the grey and white matter of the prefrontal cortex of ASPD patients? Can this result be explained?
The gray matter volume of the PFC was slightly reduced in patients with ASPD. This can be explained by the fact that ASPD patients have less impulse control and the PFC is important for impulse control. So a reduction in gray matter volume of the PFC could explain this.
What was the result of the first study where they measured autonomic nervous system (ANS) activity during a stress test?
The heart rate and skin conductance of people diagnosed with ASPD was clearly reduced.
Name brain areas that:
- are impaired only in ASPD
- are important only in moral decision-making
- are impaired in ASPD and important in moral decision-making
- Impaired in ASPD (red) → anterior cingulate (part of limbic system), temporal lobes, hippocampus, prefrontal cortex and amygdala.
- Important in decision-making (green) → posterior cingulate, prefrontal cortex and amygdala
- Impaired in ASPD and important in moral decision-making (yellow) → prefrontal cortex, amygdala, angular gyrus, superior temporal gyrus
What structures are impaired in rule-breaking behavior?
Prefrontal cortex, amygdala and angular gyrus. These structures are important for moral cognition and emotion.
What is an important structure that is impaired in ASPD or psychopaths? And how is it impaired?
The amygdala, there’s significant reduction in volume and activity.
What’s an important structure that is impaired in antisocial behavior and how is it impaired?
Prefrontal cortex is impaired, it displays robust structural and functional deficits.
What kind of technique is used to study moral decision making in psychopaths where we want to know if their behavior results from deficiencies in moral neural circuits?
functional MRI (fMRI) is used
17 subjects with varying degrees of psychopathy were asked for their judgements on 10 moral dilemmas during fMRI. What results were found?
That subjects with higher psychopathy scores, had a reduced amygdala activity during moral decision making.
What role does the amygdala have in regard to fear?
It’s important in regulation of emotions, where fear is a very important one. The amygdala does not only play a role in regulating fear, but is also important in recognising fear in others.
What else does a reduced amygdala size and activity lead to?
Besides, having less fear and not being able to recognize fear in others:
- reduced amygdale response to fearful photos
- Not good at detecting emotions (especially fear), in others’ voices or facial expressions
- Poor fear conditioning
- Unusually high disgust threshold, tolerating repellent smells and images
- Reduced empathy
ASPD patients having an unusually high disgust threshold, tolerating repellent smells and images, is not a consequence of reduced amygdala activity. What other brain region is responsible for this (and thus impaired in ASPD)?
It’s due to a reduced insula functioning.
What question is important to answer in regard to psychopaths and empathy?
- Do psychopaths lack the ability to emphasize?
Or
- Do they lack the propensity to emphasize?
The question whether psychopaths are either unable to empathize, or simply less likely to empathize in certain situations was researched. Here, psychopaths were asked to watch a movie. First they were told to just watch the movie and then they were asked to try to feel what the victim in the movie felt. What was found?
- When told to just watch the movie, psychopaths showed reduced empathy.
- When told to try to empathize with the victims in the movie, psychopaths were able to empathize.
What is the benefit of being able to empathise with others and what is a disadvantage?
- Benefit → being able to sense the inner states of other helps us to improve the capacity to predict and adapt to the behavior of others.
- Disadvantage → always exercising this is costly when you motivate others, while it depletes your own resources.
What two lines of evidence are there for the neurodevelopmental basis of antisocial behavior?
- Fear conditioning research
- Cavum spetum pellucidum (CSP) marker of limbic maldevelopment
What is fear conditioning?
It’s learning based on fear, where the amygdala associates fear with a previously neutral stimulus.
Here, for example antisocial acts are linked with negative consequences (punishment, social exclusion). In this way, we hope that antisocial behavior can be prevented.