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  • >> Good afternoon, everybody.

  • A very warm welcome to today's UCL Lunch Hour lecture.

  • It is my great pleasure to introduce Essi Viding,

  • professor of Developmental Psychopathology

  • in the UCL division of Psychology

  • and Language Sciences.

  • Professor Viding's lecture for us today is entitled,

  • Why do some people become psychopaths?

  • >> Thank you.

  • Individuals with psychopathy tend

  • to capture public imagination.

  • People are fascinated by what makes these individuals

  • so different.

  • And there has been a tendency

  • to at times sensationalize the condition and the description

  • of the condition in the media.

  • And I guess one of the signs

  • that these individuals really do capture the public imagination

  • is that they have featured in a number of popular films.

  • So here we have a picture of Jacob,

  • a character from Buckham [assumed spelling] Films

  • and he's very impulsive and he's also entirely unconcerned

  • about the impact of his behavior on other people

  • and he seems to lack empathy.

  • We have Kevin who is from the movie,

  • We Need to Talk about Kevin.

  • This is a very chilling description

  • of a child who's not capable of forming attachment relationships

  • with his parents who's cruel to animals and cruel

  • to younger children who ends up by the end of the film

  • and the book that it's based on becoming a killer.

  • He kills family members and also people at his school.

  • We have Anton Chigurh who's an absolutely chilling contract

  • killer in the current Coen Brothers film,

  • No Country for Old Men.

  • And if anyone has seen the film, I think one of very scary things

  • about observing this character is when you see shots

  • that are focused directly at his eyes

  • and there really is no emotion coming back

  • to you from those eyes.

  • And then there's probably everyone's favorite psychopath

  • from movies, Hannibal Lecter from the Silence

  • of the Lamb film; and he is again, a very good example

  • of a psychopathic character in that he's entirely void

  • of empathy for other people and he's also extremely skillful

  • at manipulating other people to his own ends.

  • And in fact, if you asked members

  • of the general public what springs to mind

  • when they hear the word psychopath,

  • people often think about serial killers.

  • And real-life serial killers include characters

  • such as Ted Bundy who killed

  • at least 30 women in America in 1970s.

  • He was very bright and extremely handsome, and he often posed

  • as somebody who was in a position of authority or someone

  • who was very reliable to entice these women to come with him,

  • and then he murdered them in a very cruel way.

  • And people think that he actually may have committed many

  • more crimes than he confessed to.

  • His description of himself was

  • that he's the most cold-hearted son

  • of a bitch you'll ever likely to meet.

  • And interestingly his defense lawyer didn't have a lot

  • of good things to say about him either and said

  • that he was the very definition of heartless evil.

  • So this was a man who was able to be very charming,

  • was able to convince other people to come with him,

  • but he actually turned out to be somebody

  • who felt absolutely nothing for his victims and didn't seem

  • to really feel any guilt for what he had done.

  • But, of course, not all psychopaths are serial killers.

  • In fact, only a very few are.

  • So what are the characteristics

  • that define an individual with psychopathy?

  • Well, one of the most prominent characteristics is their lack

  • of remorse and guilt.

  • So they simply do not feel bad about the things they have done.

  • They may sometimes say that they do if they perceive

  • that as getting them something that they want

  • such as early release from prison.

  • But it's very clear from the way they behave and --

  • that they do not actually experience remorse

  • for what they have done.

  • They don't feel bad about what they have done.

  • They're very shallow affect.

  • Their emotions appear ingenuine and often very short lived.

  • They don't form typical attachment relationships.

  • They don't look after the people around them.

  • They can often have superficial charm.

  • So if you meet these individuals for the first time,

  • you may be very, very alert by them.

  • They may seem very gregarious, very charming, very nice.

  • But once you get to know them for a longer period of time

  • that charm tends to wear off.

  • They often have a grandiose sense of self worth.

  • They think they are better

  • and more deserving than other people.

  • They're pathological liars and they are typically very good

  • at manipulating other people to their own ends.

  • As a developmental psychologist I'm very interested

  • in how these characteristics develop.

  • It's unlikely that anybody's born a psychopath

  • but clearly you don't get this sort of conditions

  • as a birthday present when you turn 18 either.

  • So the research in our group has been focused

  • on investigating what makes some children developmentally

  • vulnerable to developing these sorts

  • of personality traits as an adult.

  • And you can focus on various different levels of query

  • when you try and understand the development of this condition.

  • So we can look at how children who are at risk

  • of becoming adult psychopaths look like behaviorally.

  • What differentiates these children

  • from typical developing children or other children

  • who may have behavioral problems

  • but who don't exhibit these cold characteristics

  • of lack of empathy and guilt.

  • We can study how these children see the world around them

  • so we can use experimental tasks to focus

  • on their psychological level analysis.

  • And we can see if these children's brains react

  • differently to information around them

  • which is what you would expect if their behavior

  • and if their way of processing information is different.

  • And you can also use genetically informative designs

  • to study the relevant importance of genetic

  • and environmental factors

  • in developing this type of condition.

  • And you can also try and look for specific risk genes

  • and risk environmental factors

  • that in concert might promote the development of the disorder.

  • Now we'll first tell you a little bit

  • about what makes these children behaviorally different

  • from their typically developing peers but also

  • from other children who have behavioral problems.

  • So there are several early behavioral warning signs

  • of children who are at risk for psychopathy

  • and these look very different from the kinds

  • of characteristics we see in adult psychopaths.

  • The person who first formally downward extended this

  • psychopathic criteria to children was Paul Frick

  • and this was work that started 20 years ago

  • in the United States and now several different research

  • groups across the globe have studied these behavioral

  • characteristics in children and in young people.

  • These children lack remorse and guilt so they don't express

  • that they're sorry for what they've done.

  • They lack empathy and this can be often manifested

  • by them behaving cruelly amongst other children, bullying,

  • being very physically aggressive in a way

  • that is really showing no concern

  • over developing of the other person.

  • They are also sometimes cruel to animals

  • such as pets in the family.

  • They have shallow affects so many of the parents report

  • that they don't feel like they can connect with this child.

  • They may have a perfectly nice relationship

  • with their other children and if anyone has read the book,

  • We Need to Talk About Kevin, I think that's a very good example

  • of a mother who was able to form an attachment relationship

  • with one of her children, but really felt

  • like there was nothing coming back from the child who went

  • on to develop psychopathy.

  • These children can manipulate other people for their own gain.

  • And they have a sense of being more important

  • and more deserving than other people.

  • And in combination this constellation of traits

  • in children is called callous-unemotional traits.

  • So clearly we don't want to label children as psychopaths

  • but this constellation of traits gives you a warning sign

  • that the child who scores very high on these traits may be

  • at risk for developing psychopathy in the adulthood.

  • They're kind of like the warning sign.

  • You want to start thinking about doing something

  • to help this child if they display this constellation

  • of characteristics.

  • There's now quite a bit of good longitudinal research showing

  • that these sorts of traits are predictive of persistent,

  • violent and severe antisocial behavior and psychopathy

  • in adolescents and adulthood.

  • They don't predict that every child who's score high

  • on these sorts of traits will inevitably become an antisocial

  • adult but they do index that that child is

  • at a significantly increased risk

  • of developing the antisocial presentation in adulthood.

  • Antisocial behavior in children is called conduct problems.

  • And if you think about this circle that I'm showing to you

  • as representing all the children with conduct problems

  • and the blue circles as representing the minority

  • who also has high levels of callous-unemotional traits

  • and you get an idea that they are a minority

  • but they are a sizable minority.

  • So people estimate that somewhere between 25 to as high

  • as 50 percent of the children who are diagnosed

  • with conduct problems also have this presentation

  • of high callous-unemotional traits.

  • And what sets them apart from other children

  • with conduct problems is that they often engage in proactive

  • or planned acts of aggression.

  • So while the aggression in other children

  • with conduct problems is typically quite impulsive

  • and in reaction to something external that happened,

  • for instance, a perceived threat or slight to the child,

  • these children can engage in aggression

  • if they think it's going to get them something they want.

  • It might get them status among peers.

  • It might get them some goods that they desire.

  • As I've already said they lack guilt.

  • They don't worry about hurting other people

  • to get what they want and they often have low levels

  • of anxiety.

  • And this is in contrast with the remainder of children

  • with conduct problems who have low levels

  • of callous-unemotional traits and who often aggress

  • when they feel under threat

  • and whose aggression is often impulsive.

  • It's not premeditated.

  • And when these children have had a chance to reflect

  • on what they have done, they actually often feel bad

  • and guilty about having hurt other people

  • or having done something that has caused their parents

  • or their teachers to feel sad.

  • And this presentation can also occur

  • with high levels of anxiety.

  • So you already are beginning to see from this behavioral data

  • that the reactivity, emotional reactivity profile

  • of these two types of children

  • with conduct problems is quite different.

  • You have a group that seems to be more cold and calculated

  • and unemphatic, and then you have another group who seems

  • to be more hot headed, reactive, and impulsive

  • but who also has the capacity to empathize with other people.

  • So these different behavioral profiles have got psychologists

  • interested in how these children may see the world

  • around them differently from typically developing children

  • but also their peers with conduct problems.

  • And we can focus on the study of the psychological level

  • of analysis by giving children experimental tasks

  • which we often present on a computer, for instance,

  • and these tasks can give us an idea

  • of how they process information such as facial,

  • emotional expressions.

  • So I want you to have a go at doing one of the tasks

  • that we do with the children.

  • Here's a face that is starting

  • with a neutral rather calm expression and I'm going

  • to press a button and it's going

  • to start slowly developing an emotional expression.

  • And when you think you know what the expression is,

  • please shout it out loud and don't be shy.

  • Okay. Happy.

  • Very good.

  • So you can see fairly early on in the development

  • of this expression that this is somebody who's looking happy,

  • their corners of the mouth are going

  • up which you can see a display of teeth.

  • This is a happy looking chap.

  • And here's the same chap putting a different expression.

  • And again shout out when you think you know what emotion this

  • person is displaying.

  • Scared. So I'm hearing people say scared

  • so this is somebody who is fearful.

  • And you can see that this person is scared

  • because they are showing a lot of eye white.

  • This is one of the very, very ecologically valid signs

  • that somebody's scared

  • when their eyes are looking a little bit large

  • and you can see a lot of the eye whites.

  • Now children who have conduct problems and high levels

  • of callous-unemotional traits have difficulty in recognizing

  • and reacting to other people's emotions particularly emotions

  • of distrust, such as fear and also sadness which is --

  • you see here at the top right-hand side -- sorry.

  • Bottom right-hand side.

  • And people have used facial stimulus --

  • that's what I just showed to you to assess this.

  • But people have also used stimuli that is auditory

  • so people doing vocalizations that emotional or body postures.

  • And this work by our lab and labs

  • of our colleagues have very conclusively shown

  • that these children really do not appear

  • to process other people's emotions in a typical fashion.

  • They seem to be underreactive to these displays of emotions

  • and unable to recognize them as effectively

  • as typically developing children do.

  • Interestingly they also report feeling less fear themselves.

  • And one of the things that we're interested in researching

  • in our lab at the moment is whether the reason they have

  • such difficulty in processing other people's emotions stems

  • from the fact that they don't feel those same emotions very

  • strongly themselves.

  • So it's probably tricky to empathize with other people

  • and to recognize their emotions

  • if you have an impoverished experience

  • of those same emotions yourself.

  • We also know from standard learning paradigms

  • that these individuals who have conduct problems

  • and high callous-unemotional traits are less responsive

  • to punishment.

  • So when you have to learn about which stimuli is good to go for

  • and gives you points and which stimuli is bad to go for

  • and doesn't give you points,

  • these individuals are typically poorer

  • at modulating their behavior in response to the punishment used.

  • And people have theorized that one

  • of the reasons why these children may be tricky

  • to socialize is that two very powerful tools

  • of socializations are not as effective for them.

  • So anyone who has small children in the audience or has dealt

  • with small children knows that when they misbehave,

  • we often give them sanctions.

  • So in my house at the moment

  • with the three-year-old we have a naughty step

  • and he sits there relatively regularly and so it's something

  • that I employ in my house.

  • It's very effective.

  • He doesn't like sitting on the naughty step.

  • He said he'll kind of improve his behavior

  • and he usually comes and joins us

  • and he indeed does improve his behavior because he doesn't

  • like being excluded from the activities.

  • And we also do empathy induction.

  • So anyone who's dealt with toddlers has basically repeated,

  • well, think how Johnny is going to feel if you whack him

  • with the toy car until they're blue in the face.

  • So we try and get the children to focus

  • on how their behavior might impact somebody else

  • and somebody else's emotions.

  • Now if you are really incapable

  • of feeling perhaps those emotions yourself

  • and also feeling for other people,

  • and if you don't react very much to the punishments,

  • there are two very powerful socialization tools

  • that are not going to be as effective in bringing you

  • up as they are in typically developing children.

  • So really what we see in these children is this diminished

  • emotional responsivity to both, kind of,

  • more material punishments but also in terms

  • of their reactivity to other people.

  • And this profile is in contrast with the profile we see

  • for children who have conduct problems but who have low levels

  • of callous-unemotional traits.

  • These children, if anything,

  • seemed to be a bit emotionally overreactive.

  • They have what psychologists call a hostile attribution bias.

  • So they tend to see threat in even stimuli

  • that typical individuals don't perceive threatening.

  • So they might see an ambiguous face and think

  • that this is somebody who's trying to get at me

  • so I'm going to aggress first.

  • So in this group what we see really is increased emotional

  • reactivity at least to some types of stimuli.

  • And these data have got ourselves

  • and also other groups interested in looking

  • at how these children's brains look

  • like when we show them emotionally charged stimuli.

  • One of the ways in which we can study how the brain processes

  • information is by scanning children using functional

  • magnetic resonance imaging.

  • This is a noninvasive technique that involves scanning

  • for children's brains as they lie inside the magnet.

  • And they do tasks that we have sent to them.

  • We can then look at their brain activity

  • as they are doing the tasks and this gives us an idea

  • of what parts of the brain are engaged

  • in processing the information that we show them.

  • One of the brain areas that researchers

  • on conduct disorder have or conduct problems have focused

  • on is called the amygdala.

  • And this is a very small almond shape part of the brain.

  • It's a very preserved structure even reptiles have it.

  • It's there for basically alerting you

  • that there's something salient in the environment

  • that you're to pay attention to.

  • And this salient information

  • for human beings includes emotions of other people.

  • And studies of children

  • with conduct problems using emotional stimuli have been a

  • little bit mixed.

  • Some studies have reported increased amygdorial [assumed

  • spelling] reactivity to emotional stimuli.

  • Other studies have reported decreased amygdorial reactivity

  • to emotional stimuli.

  • And our group recently wanted

  • to investigate whether it's the callous-unemotional traits

  • that determine whether the children's brains are

  • underresponsive or the amygdors are underresponsive

  • to emotional stimuli

  • or overresponsive to the same stimuli.

  • So we have carried out a range of paradigms recently.

  • I will talk about two here in the talk.

  • And here's an example of a recent task

  • that we've used called masked fear task.

  • And in this task we presented either fearful faces which is

  • on the left-hand side there or calm faces which is

  • on the right-hand side there

  • for very short duration, only 17 milliseconds.

  • And then we replaced those faces with a calm face

  • of a different identity.

  • And the replacement of the face happened so quickly

  • that the participants are not consciously aware

  • that they've seen a fearful face.

  • So the advantage of this task is that we can look

  • at very early preconscious processing of emotion.

  • In other words, we get an idea

  • of how automatically the brain attunes

  • to the emotional stimuli.

  • And when we contrast the fear

  • and the calm conditions we find a pattern of brain responses

  • where children who have conduct problems

  • and high callous-unemotional traits show very low amygdorial

  • reactivity to these preconsciously presented

  • fierce stimuli.

  • The typical children are somewhere in the middle

  • and the children with conduct problems

  • and low callous-unemotional traits show, if anything,

  • overreactivity to these fear faces

  • that we present pre-attentively.

  • And here I'm showing you a plot of the data from the children

  • with conduct problems alone.

  • And on the left-hand side

  • on the Y axis you can see the brain activity estimates

  • from the FMRI analysis

  • and on the right-hand side you can see the child's

  • callous-unemotional traits score.

  • And you can see that the higher the callous-unemotional trait

  • score, the lower the amygdorial response to these fearful faces.

  • We also used a more complex emotional tasks such as the task

  • that showed scenarios of other people in distress.

  • So this was a cartoon task where the children saw a scenario

  • where the mother is reading a newspaper, a child is going

  • down the slide, and the child ends up hurting himself

  • and falling off the slide.

  • And then the person inside the scanner gets two choices

  • as to what is the appropriate ending to the task.

  • And most children even the children

  • with conduct problems are very able to say

  • that the appropriate response is for the adult to go

  • and comfort the child.

  • So behaviorally the children --

  • process this task very similarly.

  • But interestingly again, the amygdala of the children

  • with conduct problems particularly those children

  • with conduct problems

  • and callous-unemotional traits is less reactive

  • to observing other people in distress

  • in this very complex social scenario.

  • And the kind of contrast we can use

  • in a scanner is we have a similar scenarios

  • but without the emotional contents

  • so we can really extract the emotional response of the brain.

  • So the data from this behavioral psychological

  • and brain emitting studies is really showing this picture

  • of shallow affect and lack of empathy and demonstrating it

  • in different levels of analyses.

  • So we know from naturalistic behavioral settings

  • from more experimental behavioral settings and also

  • from brain imaging settings that these children really seem

  • to have this underreactivity to other people's emotions,

  • perhaps particularly distress.

  • So these sort of data obviously begs the question

  • as to why do these children process the information

  • around them so differently.

  • Are they genetically at risk for being this way?

  • Are there some environmental risk factors that mean

  • that they come to be very unemphatic,

  • very emotionally underreactive.

  • And one of the ways in which you can wrote the origins

  • or the etiology of any given trait or disorder is

  • by classical twin design.

  • And the twin design relies on a comparison between identical

  • or monozygotic twins and nonidentical or dizygotic twins.

  • The identical twins are the result

  • of a single fertilized egg splitting so they are

  • for all intents and purposes each other's genetic clones.

  • And an example I often use here, I run the research group

  • with Dr. Eamon McCrory who's an identical twin.

  • And his brother has three children

  • but if they did a paternity test,

  • they couldn't tell whether it's the brother

  • or whether it's Eamon who's the father.

  • So these are two individuals who have identical DNA.

  • Then we have nonidentical or dizygotic twins

  • who are the product of two separate eggs being fertilized

  • by two separate sperm.

  • So they're like any other sibling pair

  • but they have been born at the same time

  • which makes them a good comparison in the studies

  • for the identical twins.

  • And you can use the twin studies to infer the relative importance

  • of genetic and environmental influences

  • on variation on any given trait.

  • And the way you can do it is you can compare how similar do these

  • clones look to each other on any given behavior

  • and how similar do these nonidentical twins look

  • to each other on any given behavior.

  • And you can conclude that there is more than likely

  • to be genetic influence on a trait

  • if the identical twins look more similar to each other

  • than the nonidentical twins.

  • So if genetics are important in driving similarity,

  • then the individuals who share hundred percent

  • of their DNA should look more similar to each other

  • than individuals who share on average 50 percent of their DNA.

  • You can also conclude that there may be environmental factors

  • that make family members similar to each other.

  • If the nonidentical twins correlate with each other

  • or resemble each other more than the half

  • of the identical twin resemblance.

  • So if you think that only genetics are important

  • for driving similarity then the dizygotic twin resemblance

  • should be exactly half of the identical twin resemblance.

  • Now if the dizygotic twin resemblance is actually larger

  • than half the identical twin resemblance, this tells us

  • that there are some environmental factors that act

  • over and above genetic factors to promote similarity

  • between family members.

  • And we can also infer that there are some individual specific

  • or nonshared environmental factors

  • if the identical twins are not 100 percent identical

  • in the trait.

  • So these [inaudible] of the genetic clones to the extent

  • that they differ on any given feature,

  • there must have been some environmental influences

  • that differed between the twins.

  • And an example I often use to drive this point home is

  • if you manage an identical twin who grew up in Britain

  • versus an identical twin who went to live in Australia,

  • you would expect that there are chances and differences

  • in pigmentation between these twins because one

  • of them is exposed to constant sun and the other one has

  • to deal with the kind of weather

  • that we've been having last week.

  • So this is environmental factor that differed between the twins

  • and drives differences between family members.

  • And we have used the twin design

  • to ask whether there are differences

  • in the relative importance of genetic

  • and environmental factors for the development

  • of conduct problems in children

  • who have high callous-unemotional traits

  • and in children who have low callous-unemotional traits.

  • And I've been fortunate to work with a very big twin registry

  • that is headed by Robert Floman [assumed spelling]

  • of the Institute of Psychiatry here in London.

  • And what we were able to do

  • because this was a very large twin sample is

  • to select those children who are in the top 10 percent

  • for conduct problems for the twin sample.

  • So they are scoring

  • in an atypical range for conduct problem.

  • And then we divided this extreme group to two.

  • We took those children where either 1 or 2 members

  • of the twin pair also scored in the top 10 percent

  • for callous-unemotional traits.

  • And then we looked at children where neither member

  • of the twin pair scored in the top range

  • for callous-unemotional traits.

  • And within each of these groups we were able

  • to compare the identical and nonidentical twins

  • to give us an indication

  • of how heritable are the conduct problems for children

  • who have callous-unemotional traits

  • and how heritable are conduct problems for children

  • who have low levels of callous-unemotional traits.

  • What we found was that for children

  • who had high callous-unemotional traits the conduct problems were

  • strongly heritable.

  • Whereas for children who had low levels

  • of callous-unemotional traits environmental influences both

  • shared and nonshared were more important

  • for the development of conduct problems.

  • Now that doesn't mean that the children

  • who have high callous-unemotional traits are

  • somehow genetically destined to become antisocial.

  • And but it does mean that they will probably have more

  • vulnerability, innate vulnerability

  • for developing conduct problems.

  • Similarly it doesn't mean that the children who have low levels

  • of callous-unemotional traits have no genetic risk whatsoever

  • but it may be that that takes different form

  • and may require some environmental factors to express

  • or more environmental factors that you may need

  • to express this vulnerability

  • if you have high callous-unemotional traits.

  • Of course the twin studies only give us an idea

  • of the relative importance of genetic

  • and environmental factors

  • and they don't tell us what the actual genes are

  • or the actual environments.

  • And currently there is very scarce data

  • about the actual genes and actual environments particularly

  • for children with high callous-unemotional traits.

  • So ourselves and other people have speculated

  • that the risk genes for high callous-unemotional traits

  • and low callous-unemotional traits type antisocial behavior

  • may be different.

  • And this would be in line with the fact

  • that the other group is associated

  • with low emotional reactivity whereas the other one is

  • associated with high emotional reactivity.

  • So in a way you would expect there

  • to be different vulnerability genes for the two groups.

  • Perhaps genes that confer low emotional reactivity

  • and arousal indicates children

  • with high callous-unemotional traits,

  • and there's certainly some data to support

  • that this may be the case.

  • So a genotype called serotonin transporter polymorphism has

  • been associated with callous-unemotional traits

  • and the allele or the type of that genotype

  • that was associated was the one

  • that confers slower emotional reactivity.

  • We know that from imaging genetic studies.

  • But this is just a single study.

  • Interestingly this genotype only conferred risk in children

  • who lived in low resource neighborhoods.

  • So it suggests that you may have propensity

  • to lack emotional reactivity or lack empathy.

  • But whether that expresses itself

  • as callous-unemotional traits or not may depend

  • on your environmental conditions.

  • There are also some studies that have suggested the genes

  • that may be associated

  • with attachment processes could be important

  • such as the oxytocin receptor gene.

  • But ultimately there haven't really been replications

  • of these findings.

  • We have ourselves conducted a genome line association study

  • which means that we combed

  • through the whole genome looking whether there is anything

  • that crops up and there really weren't any big hits.

  • And there hasn't been [inaudible] case

  • in either our study or any of the other studies.

  • So it's very early days.

  • But if this particular phenotype goes in line with what we know

  • from other behavioral phenotypes and I have no reason to expect

  • that it would be different, we're likely

  • to be spending a long time looks for those genes.

  • They are going to be small genes that probably -- sorry.

  • Genes with small effect size

  • that probabilistically increase the risk

  • for developing this sort of behavioral outcome

  • and it is more than likely that any

  • of this genotypes will require the presence of other risk genes

  • and environmental risk factors in order

  • to penetrate as a risk phenotype.

  • Again, ourselves and others have proposed that for those

  • with no callous-unemotional traits we might be interested

  • in looking for genes that confer high arousal

  • and reactive aggression.

  • And again there's some sensitive data suggesting that these sort

  • of genotypes may be associated

  • with the low callous-unemotional type of antisocial behavior.

  • And genome interaction may be particularly important

  • with regard to this subtype.

  • So there are a number of good studies suggesting

  • that if you have a polymorphism of monoamine oxidase A gene

  • that confers increased unemotional reactivity.

  • And if on top of that you experience maltreatment,

  • then you are at substantial increased risk

  • for developing conduct problems.

  • But very, very early days and all

  • of these studies need more replications

  • and we probably need to really wait for a lot

  • of methodological developments before we can reliably start

  • finding genes associated with this condition.

  • Similarly, the risk environments may differ

  • for the two condition.

  • So we have reasonably good data

  • for the low callous-unemotional trait subgroup.

  • It's reliably associated with hard

  • and inconsistent parenting and maltreatment.

  • But we have less of an idea

  • of what our environmental risk factors that promote development

  • of callous-unemotional traits.

  • And our own work using identical twin differences design

  • where we rely on the fact that they are each other's clones

  • and any differences in phenotype and risk response

  • to environmental factors such as parenting should be

  • where we can reliably say that that's environmental.

  • Using that sort of methodology we haven't been able to show

  • that hard and inconsistent parenting, for instance,

  • predicts increase in callous-unemotional traits.

  • So that doesn't seem to be something

  • that impacts development of those traits or at least not

  • as reliably as it does for the children

  • who have low callous-unemotional traits.

  • And there's some very interesting early data.

  • There's a funny looking carafe with lots of little data points

  • but I will talk you through it.

  • Paul Frick and his colleagues looked at the relationship

  • between hard and inconsistent parenting and conduct problems.

  • And when you look at children who have conduct problems

  • and low callous-unemotional traits,

  • you can see this [inaudible] response relationship.

  • The higher the frequency of hard and inconsistent parenting,

  • the higher the level of conduct problems for these children.

  • But in contrast children who have conduct problems

  • and low levels

  • of callous-unemotional traits appear to have high levels

  • of conduct problems regardless of whether they receive less

  • or more of the hard and inconsistent parenting.

  • Now this is not to say

  • that environmental influences don't matter

  • for these children at all.

  • And in fact there is some very interesting new work showing

  • that for instance parental warmth is associated

  • with lower levels of callous-unemotional traits.

  • So the children may be responsive

  • to some positive environmental influences.

  • There have also been treatment studies that have shown

  • that some parenting focused interventions can be effective

  • in reducing callous-unemotional traits and conduct problems.

  • And there is a Meads [assumed spelling] and --

  • study showing that if you add empathy training

  • to normal parent training programs,

  • children who have high levels of conduct --

  • callous-unemotional traits may particularly benefit

  • from this sort of training.

  • At least when it's done with children who are

  • at the preschool, early primary school age range.

  • So some evidence that there are protective environmental factors

  • that can be very helpful for these children.

  • So why do some people become psychopaths?

  • I'm afraid that we have only taken baby steps sofar

  • in terms of research.

  • So we have some inclination but we really don't have a good idea

  • of the development trajectory particularly

  • at different levels of analysis.

  • So there's indication that these children may be more genetically

  • vulnerable but I hasten to add not genetically destined

  • for this sort of outcome.

  • It may be that they lack environmental buffers

  • or they have some risk environmental factors

  • which we don't know what they are that mean

  • that the genetic vulnerability expresses itself

  • as callous-unemotional traits.

  • And we know that they are not very emotionally reactive,

  • empathetic and sensitive to punishment and this sort

  • of presentation at the cognitive emotional level is probably

  • going to make them more resistant

  • to typical socialization efforts.

  • But we also know from longitudinal studies

  • that not all children who have conduct problems

  • and high callous-unemotional traits grow

  • up to be adults with psychopathy.

  • So we really do need more longitudinal studies

  • that combine different methodologies and will enable us

  • to really study what are the environmental risk factors.

  • How may they be different at different time points?

  • How do they influence the development

  • of these children's cognitions and affect processing?

  • So how does the atypical emotion develop over time?

  • And it's interesting to find out that this is something

  • that we are studying at the moment

  • in our group is whether these children can empathize

  • under any circumstances.

  • So if we focus their attention differently or if we use stimuli

  • that they themselves report as sadness or fear inducing,

  • do we then see an emotional response.

  • And if we do can that be harnessed

  • to teach them a bit more about how

  • to empathize with other people.

  • So can we help them to see the world differently?

  • I think that's kind of an important research question

  • for the next 10, 20, 30 years.

  • I know that there are specific interventions being developed

  • that really focus on the difficulties

  • that these children experience and I'm sure

  • that there will be a lot of cross talk

  • between these interventions and the basic science researchers.

  • Some of our basic science findings will feed

  • into how these interventions are tailored more specifically

  • to meet the needs of these children.

  • And of course there is the hope

  • that eventually there will be very few of the individuals

  • who develop psychopathy as an adult outcome.

  • I want to finish by very much acknowledging all the people

  • who are working on our team at the moment and who've worked

  • on our team in the past.

  • This sort of research requires a lot of theoretical knowledge,

  • technical skills, statistical skills, and first

  • and foremost a lot of people skills

  • and when we recruit the samples so when we test the children,

  • we have a very capable team of people

  • who are involved in the research.

  • And I particularly want

  • to acknowledge Eamon McCrory who's there at the Center

  • with me who codirects the research group with me.

  • And also I want to acknowledge the people

  • who are very generously funded our research.

  • And I'm very happy to take questions.

  • Thank you.

  • [ Applause ]

  • And I should also mention that you can go to our lab's website

  • and there will be information about our research

  • and materials in that website.

  • >> Thank you very much.

  • Thank you very much.

  • We have time for one question.

  • >> Sorry.

  • >> Anybody has a good question.

  • It has to be the very best question that can be asked.

  • >> If our high callous-unemotional traits are

  • genetic, that would suggest that maybe one or both

  • of the parents also share some of those traits;

  • so could that be an environmental factor leading

  • to problems?

  • >> So that's an excellent question.

  • So the question was that if these traits are heritable and 1

  • or 2 of the parents share the traits does that mean

  • that the child is more likely to be exposed

  • to environmental risk.

  • In short, yes.

  • It's a phenomenon that we call gene-environment correlation

  • which is that the parents parent according to that genotype

  • that they pass on to their children so that the child kind

  • of has the double whammy of having genetic vulnerability

  • and then perhaps having a parent who's not really able

  • to provide the optimal parenting environment either.

  • There is some interesting data suggesting

  • that that may not always be the case so there's data

  • from colleague of mine in Australia,

  • Mark Datt [assumed spelling] that has looked

  • at how the children and the parents engage with each other

  • and interestingly at least in the case of the mothers,

  • the mothers of these children try and look for eye contact,

  • try and engage the children just in the same way

  • as any typical mothers do,

  • but the children themselves don't engage in the same way

  • so they don't look the mothers in the eyes.

  • They don't kind of give back in the same way.

  • So while I'm sure that you're right that there are a number

  • of times where the environment is also impoverished

  • because of the parents vulnerability.

  • It's not always the case and sometimes these kind

  • of attachment difficulties may be driven by the child

  • and the very difficult temperament that the child has.

  • >> Thank you very much.

  • Will you join me in thanking Professor Viding again

  • for an excellent lecture?

  • [ Applause ]

>> Good afternoon, everybody.

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なぜサイコパスになる人がいるのか?(2014年1月30日) (Why do some people become psychopaths? (30 Jan 2014))

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