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Morality and psychopathy

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					Morality and psychopathy
  Cognitive Neuroscience 2008
    Anu Pasanen & Ana Lee
Contents


                                                             Page:


Introduction                                                  3


Psychopathy                                                   3


Diagnosis of psychopathy                                      4


Moral                                                        4–5


Neurobiology in psychopathy                                   6


Genetics behind psychopathy and its relation with morality   7–9


Future prospects                                              10


Summary                                                       10


References                                                    11
Introduction


Morality and psychopathy are in part intriguingly connected to each other. Psychopathic tendencies
involve a large variety of moral transgressions such as manipulation, constant lying and violations
of socially appropriate behaviour. In the light of present knowledge, morality seems to involve many
          (2)
classes     , of which especially the care based morality is of great importance in our examination of
morality in psychopathy: Why do not psychopaths seem to care, and on the other hand, why do
healthy people care of what is good to others? It has been said that psychopathy is a disorder of
                  (1)
the moral brain     . Thus, most commonly dysfunctional brain areas in psychopathy, amygdala and
ventromedial prefrontal cortex (vmPFC), and their role in the development of moral, may shed
some light on this issue (4). In this essay, we are going to discuss what kind of neurobiology is most
often observed in psychopathic brain and what might be the possible underlying factors behind the
disease. Is it the genetics or the environmental factors that have the major contribution to the onset
of the disease? We will also briefly discuss what kind of genetic features are often observed in
psychopathy. We are starting with the definition and clinical assesment of the disorder and ending
with prospects of a possible treatment and suggestions for further studies in the future.


Psychopathy


Psychopathy is a developmental disorder comprising a range of interpersonal, affective and
behavioural (lifestyle) features, such as manipulation and deception, grandiosity, shallow emotions,
lack of empathy and remorse, an irresponsible lifestyle and persistent violation of socially
                          (1)
appropriate behaviour       . Psychopathic disorder is categorized under antisocial personality
                                                                    (6)
disorder (APD) and many psychopaths meet the criteria for APD         . However, antisocial behaviour
features are only one side of psychopathy and also certain kinds of interpersonal and emotional
traits are included as mentioned above. Nevertheless, psychopathy is one of the strongest
predictors of persistent and severe criminal conduct. It has been estimated that roughly 50% of
                                                        (5)
severe crimes have been conducted by psychopaths          . Besides their other features, psychopaths
often posses charm and charisma which they use to get into their objectives. This is illustrated for
example by some religious cult leaders in history, who have been able to lure a group of followers
(BBC Online Network).
Diagnosis of psychopathy


In clinical evaluation of psychopathy, most widely used instrument is the Psychopathy Checklist-
          (5)
Revised     . The methods used in PCL-R assesment are a semistructured interview and case
history information. During the assesment, 20 spesific items measuring salient elements of
psychopathic character are scored on a 3-point scale. Partial demostration of the twenty traits
assessed by the PCL-R score could be: glib and superficial charm, grandiose (exaggeratedly high)
estimation of self and pathological lying. PCL-R score indicates a degree of psychopathy in a
                                                                                                       (8)
tested patient; The "perfect" score is where a classic or prototypical psychopath would rate             .
Recently, PCL-R method in evaluation of psychopathy has also gained some critics concerning for
example its predictive validity (JRank).
        In childhood or adolescence, either the Antisocial Process Screening Device or
Psychopathy Checklist: Youth Version (2) are predominantly used.
Assesment of psychopathy with the evaluation methods mentioned above should always be done
clinically by experts.


Moral


Emotions seem to be important in development of moral. There is an ample amount of scientific
literature concerning impaired recognition of fear-related stimuli in psychopathy. Difficulties in
emphatic responding and impaired processing of sadness fear of others in people with
                                                                                                 (4)
psychopathy may lead to different moral judgements than observed in healthy people                 . As a
consequence to decreased recognition of fearful expressions, people with psychopathy show
                                                   (2)                                    (2)
impairment for example in aversive conditioning          and passive avoidance learning         which are
important for development of some classes of moral (2).
        Moral in general have been described to refer to a code of conduct put forward by a society
or, some other group, such as a religion, or accepted by an individual for her own behavior or
normatively to refer to a code of conduct that, given specified conditions, would be put forward by
all rational persons (Stanford encyclopedia of philosophy). In the light of present knowledge, it
appears that there are multiple, partially separable neuro-cognitive structures that mediate specific
aspects of morality: Social convention, care-based morality, disgust-based morality and
fairness/justice (3).
Care-based morality is a form of moral reasoning concerning actions that harm others and people
                                                           (4)
with psychopathy seem to lack this kind of moral             . This might be due to their lacking ability to
separate moral and conventional transgressions, because this distinction has an effect on how
moral judgements are made. Moral transgressions have been determined based on their
consequences which concern the rights and welfare of others, whereas social conventional
transgressions have been determined as violations from what is seen appropriate behaviour
concerning social interactions. Healthy people distinguish between moral and conventional
                                                                                       (4)
transgressions from the age of 39 months and this occurs across cultures                 . Moral transgression
could be for example one person hitting another, while social conventional transgression could be
                                             (4)
dressing in clothes of opposite gender         . Moral-conventional distinction occurs in several different
ways. For example, conventional transgressions are usually judged less seriously than moral ones.
                                                                                                             (3)
Second,     conventional     transgressions        are   judged   differently   from    moral   violations     :
Transgressions that cause harm for another are distinguished from violations that cause social
           (2)
disorder     . Because of the lacking moral-conventional distinction and flattened emotional
reactions, people with psychopathy make different judgements compared to healthy people. This
situation will be illustrated later in context of vmPFC damage.
       There are few propositions to how moral-conventional distinction might have arisen. First it
was suggested that the separation evolved as a function of conscious abstract reasoning
             (4)
processes        . However, children with autism also display moral-conventional distinction, yet they
                                       (4)
have impaired abstract reasoning         . Currently, it is the role of emotion that is thought to be
important for development of moral-conventional distinction (4).
       Disgust based morality is currently believed to be intact in people with psychopathy,
because brain regions that mediate this kind of morality are not thought to be dysfunctional in
                               (3)
people with psychopathy          . Disgust can be considered a strong emotional attitude towards
transgressions, and disgust expressions in social interaction might be used in similar manner with
fear expressions in emotional learning involving amygdala. It is proposed that disgust expressions
initiate taste-aversion learning which is mediated by insula. This means that we might learn to
connect disgust reactions to certain transgressions by seeing other people to show disgust towards
these transgressions (4).
Psychopathy can help us to understand moral, because pathology in individuals with psychopathy
has effects on relatively specific series of systems (2), which will be considered next.
Neurobiology in psychopathy


Two core neural regions that are most commonly described to be dysfunctional in psychopathy are
the amygdala and ventromedial prefrontal cortex (vmPFC), which are both involved in moral
reasoning. Amygdala is essential for learning of care-based morality, which means learning that
some actions cause harm to others and should be avoided. In other words, amygdala enables the
learning of right and wrong. Learning is thought to occur in stimulus reinforced fashion, which
enables representations of conditioned stimuli within temporal cortex to be associated with
emotional responses mediated by amygdala. For example, affective responses mediated by
amygdala can be linked with the victims fear or sadness. In psychopathy, this aversive conditioning
and response to other peoples fear is impaired (4).
        Amygdala forwards outputs to the vmPFC, which is essential to normal generation of
emotions and social emotions. VmPFC plays a vital role in deciding what is right or wrong in some
moral dilemmas. People with vmPFC damage have been reported for example to show reduced
emotional responsivity and reduced social emotions, like shame, guilt and compassion, which are
tightly associated with moral values. Compared to healthy people, individuals with vmPFC damage
have been reported to make more utilitarian judgements in moral dilemmas that involve some
strong emotional component. For example, people with vmPFC damage would sacrifice a life of
one person to save lives of many people, while healthy people wouldn`t sacrifice that person. By
making these kinds of moral judgements, vmPFC patients are thought to aim into solutions that
maximaze aggregate welfare. This happens, because emotional reaction doensn`t occur or is mild
and thus vmPFC patients rely their decisions on explicit norms endorsing the maximization of
overall well-being (7).

        Recently, the volume of grey matter (GM) in the brain in people with psychopathy has also
been studied. It has been observed that patients with high psychopathy scores have decreased
grey matter volumes in brain regions that play important roles in social conduct, such as the
frontopolar cortex and superior temporal sulcus region (1).
Genetics behind psychopathy and its relation with morality


Results of several studies have indicated that psychopathy can be linked to a gene despite the
available data are suggestive.            Individuals who are II homozygote for the 5-hydroxytriptamine
transporter gene show reduced amygdala response to emotional expressions, relatives to those
                                                                         (4)
who have the short-form polymorphism of the gene                           .    Understanding the 5-HTTLPR gene
provides a new foundation for understanding the neurobiologal and genetic basis of emotional
regulation and affective illness.
       The 5-HTTLPR plays an essential role in determining the duration and intensity of the 5-HT
communication with its receptors on postsynaptic targets such as those located in limbic regions
mediating emotion, and with presynaptic receptors that exert inhibitory control over the 5-HT
neuron itself (see Fig. 2). A low-expressing form, the S-allele, cause significant less 5-HTT mRNA
transcription and 5-HTT binding, and reduced platelet 5-HT reuptake, compared to the normal
expressing form. Reduced 5-HT1A receptor binding in the human brain has also been reported (8).




    Fig. 1 Effects of 5-HTT gene variation on human 5-HT neurotransmission a) Release of 5-HT with no
    mutations in 5-HTT b) Increased activation of presynaptic autoreceptors on 5-HT neurons caused by the
    S-allele.
As a result of loss of 5-HTT gene function impaired clearance and elevation of extracellular levels
of 5-HT in the forebrain region including the frontal cortex may occur. The evidence for         the
hypothesis, abnormalities in emotional regulation relates to 5-HTT dysfunction, came from
evidence that drug-free patients with mood and anxiety disorders exhibit significant reductions in
brain 5-HTT binding relative to normals (8).
       Then, Lesch and Murphys and colleagues described a common genetic polymorfhysm in
the human 5-HTT gene (SLC6A4) located on the chromosoom 17q11.1-q12 (see Fig. 2). This
polyphormic region is a variable repeat sequence in the promoter region of the region that encodes
the two forms of alleles: a short form, the s-allele comprising 14 copies of a 20-23 base pair
irregular repeat and a long form comprising 16 copies. As mentioned before findings indicate less
5-HTT transcription, expression and function in s-allele carriers than in l-allele homozygotes. It is
still a discussion though whether differences between individuals carrying a S-allele is comparable
because experiments with human subjects is inherently difficult to perform and not all studies has
been able to detect clear effects of the 5-HTTLPR on 5-HTT ability. There are several factors
including sex, age and imaging methodology which can contribute to the discrepancies across
studies. There is also evidence that additional regulatory variation within the 5-HTT gene
influences transcription and biases the ability to detect effects of 5-HTTLPR.




     Fig. 2 The 5-HTTLPR gene located on the chromosoom 17q11.1-q12
The 5-HTT gene function has different phenotypes and thus several effects on stress-activity. Loss
of the 5-HTT gene function not only biases towards increased anxiety but also exerts a negative
influence on the ability to cope with stress. Previous studies showed that stress can increase the
risk for emotional disorders. It does it in a manner suggestive of a strong genetic influence but
identifying the specific genes involved in the process has been difficult. However, a study of Caspi
and colleagues found that individuals with the s-allele were more likely to suffer from major
depression, but crucially only if they suffered from multiple traumatic life events such as childhood
abuse or neglect. This is interesting consider the fact that the amygdala goes up while one is
having a trauma and with psychopathy the amygdala activity is reduced. Moreover the amygdala
activity will be described later on the essay. Also reduced activity in vmPCF in response to
emotional words in the context of emotional memory paradigms and during aversive conditioning
has been reported. For example, Rhesus macaques carrying an orthologue of the 5-HTTLPR s-
allele have been found to exhibit exaggerated behavioural and neuroendocrine responses to stress
and abnormalities in 5-HT metabolism, but only when reared in a stressful environment (8).
       Genetically changes in 5-HTT functions affect both structure and function of key
corticolimbic pathways regulating the brain’s capacity for effectively dealing with stress which can
lead to emotional disorders like psychopathy. Recent evidence suggests that these neural
differences in affect and temperament that are associated with 5-HTT variation. Thus with sufficient
stress on the system, heritable differences in the corticolimbic reactivity could significantly impact
vulnerability to affect illness, this has to be proven yet.
       As mentioned before the neuropsychological literature on phsychopathy has described two
core neural regions that seem to be dysfunctional in psychopathy: the amygdala and the vmPFC.
The amygdala is known to be crucial for stimulus-reinforcement learning including learning the
goodness and badness of objects and actions, whether vmPFC processes affect only those moral
                                                     (3)
judgements involving emotionally salient actions       . So, the question arises; can someone with low
or no morals at all be called a psychopath or is it more than that? The answer remain to be
answered as we know little about the disorder and the cause of it but it is definitely good to keep in
mind that we still have loads to discover in this matter.
Future prospects


Regardless of the fact that amygdala-/vmPFCdamage is often observed in psychopathy, the
disorder is not a neurological condition and is not associated to damage on some particular region.
Besides amygdala and vmPFC, there might also be disruptions in other neural structures
associated with psychopathy. One such region is for example dorsal anterior cingulated cortex
         (4)
(dACC)     , but the role of it and other structures need to be studied more in detail the future. It
should also be evaluated if the PCL-R method for clinical assessment of psychopathy is adequate
in the future and if not, what would be a better tool.
       As for treatments in psychopahty, with the data now available two potential hypothesizes
are interesting. The first one is genetic polymorphism. By understanding the molecular genetics of
psychopathy, it should be possible to develop pharmacological treatments. The second one is
based on the pathopsysiology of psychopathy. There are already pharmacological agents existing
which modulate amaydala activity. Such agents target serotonergic or noradrenergic systems.
Many nowadays research are focused on the downregulation of the amygdala activity and thereby
its emotional responding, thus it is not unimaginable to also find a way to specificly upregulate the
amygdala activity.




Summary


Psychopathy is a developmental disorder that has interpersonal, affective and behavioural
                       (1)
(lifestyle) features     . In clinical evaluation of psychopathy, most widely used instrument is the
Psychopathy Checklist-Revised (PCL-R; Hare 1991, 2003), which gives the patient the score
illustrating a degree of the disease. Recent studies indicate that there might be many at least partly
separable moral systems (3). People with psychopathy seem to lack care-based morality, which has
to do with actions that cause harm to others. An early developmental indication of care-based
morality is moral-conventional separation, which is observed in healthy people from 39 months. In
psychopaths, significantly less of moral-conventional separation occurs and it is often thought to be
due to lack of appropriate emotional responding. Two core neural regions described to be
dysfunctional in psychopathy are amygdala and ventromedial prefrontal cortex (vmPFC). These
                                                             (4)
structures are essential for normal moral development          . Treatment for this disorder is not
unthinkable in the future.
References
[1]
       De Oliveira-Souza, R., Hare, R.D., Bramati, I.E., Garrido, G.J., Ignácio, F.A., Tovar-Moll, F., Moll, J. 2008. Psychopathy as a
       disorder of the moral brain: Fronto-temporo-limbic grey matter reductions demonstrated by voxel-based morphometry.
       NeuroImage 40, 1202-1213.
[2]
       Blair, R.J.R. 2006. The emergence of psychopathy: Implications for the neuropsychological approach to developmental
       disorders. Cognition 101, 414-442.


[3]
       Blair, J., Marsh, A.A., Finger, E., Blair, K.S., Luo, J. 2006. Neuro-cognitive systems involved in morality. Philosophical
       Explorations 9 (1).


[4]
       Blair, R.J.R. 2007. The amygdala and ventromedial prefrontal cortex in morality and psychopathy. Trends in Cognitive
       Sciences 11 (9), 387-392.


[5]
       Hare, D.R., Neumann C.S. 2008. Psychopathy as a clinical and empirical construct. The annual review of clinical psycholochy.
       4, 217-246.


[6]
       Holmqvist, R. 2008. Psychopathy and affect consciousness in young criminal offenders. Journal of interpersonal violence. 23
       (2), 209-224.


[7]
       Koenings, M., Young, L., Adolphs, R., Tranel, D., Cushman, F., Hauser, M., Damasio, A. 2007. Damage to the prefrontal cortex
       increases utilitarian moral judgements. Nature 446 (7138), 908-911.


[8]
       Hariri, A.R., Holmes, A. 2006. Genetics of emotional regulation: the role of the serotonin trnasporter in neural function.
       TRENDS in Cognitive Neuroscience 10 (4), 182-191


[10]
       David, S.P. et al. 2005. A functional genetic variation of the serotonin (5-HT) transporter affects 5-HT1A receptor binding in
       humans. J.Neurosci. 25, 2586 – 2590




Online references


-      BBC Online Network. World. Official commentary slams Falun Gong "fallacies". Available:
-      (http://news.bbc.co.uk/1/hi/world/monitoring/401725.stm). 23.07. 1999.
-      JRank. Other Free Encyclopedias: Law Library - American Law and Legal Information: Crime and Justice Vol 3: Psychopathy
       What Is Psychopathy?, Psychopathy And The Criminal Law, Bibliography. Available:
       (http://law.jrank.org/pages/1884/Psychopathy-What-psychopathy.html) 2008.
-      Stanford encyclopedia of philosophy. The Definition of Morality. Available: (http://plato.stanford.edu/entries/morality-
       definition/). Last modified 11.2.2008.
-      http://www.nature.com/neuro/journal/v10/n9/images/nn1964-F1.jpg

				
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