Nature vs Nurture in Violence: Forensic Psychiatry Insights

Hello cruel world. My name is Dr Sohom Das.  I'm a Consultant Forensic Psychiatrist.   I assess mentally disordered offenders for a  living, so that you don't have to. Today i'm going   to tackle quite a big question in the world of  criminality which is this, nature versus nurture  

when it comes to violence. So this is an age-old  question like how old is the universe? Is time   travel possible? and why do men have nipples? So  in this episode i'm going to give you a couple of   very brief case examples of patients that I have  assessed just to give you a kind of overview of  

some environmental factors. then i'm going to  really quickly summarize some of the research   in this area but don't worry i'll make it quick  and less as least boring as possible. I'm going   to talk about some specific environmental factors  and how they lead to violence. I'm going to talk  

about mental health and personality factors  because after all that is my area of expertise   and i'll talk about some of the genetic factors  as well and finally I am going to tell you   about some theories which bring in some of these  factors together. They're kind of social theories.  

So sit back and relax welcome to A Psych for Sore  Minds. I elevate while you vegetate.. no sorry I   educate while you vegetate. So one thing I would  say is i've assessed hundreds of criminal cases   and the vast majority of the time they have lots  of environmental factors and they are things  

like poverty, drug abuse, domestic violence,  being the victims of physical or sexual abuse,   the perpetrators that is when they're younger,  poverty did I say that? drugs and alcohol these   are very common. The vast majority of patients  that I see have these factors, in fact it's so  

common that when I see patients that don't have  those factors they really stand out in my memory.   One absolutely major one has to be a case that  i've spoken about very recently in a video the   most shocking case of any of my patients. A young  18 year old girl who's got this unblemished past,  

she has never been antisocial, no drugs, no family  history of criminality, never got into trouble,   out of the blue she became psychotic and  tragically she um smothered and killed her   two-year-old nephew who she was babysitting at the  time. The reason I bring up this case is because  

even though she had no environmental factors,  it's very clear that her mental illness directly   led to her offending. Another case that really  stands out was very early on in my career. I   met this young man in a medium secure unit. He  was in his early 20s and he was also unusual in  

that he came from a very privileged background. So  for example he was privately educated. For those   people outside the UK, about seven percent of our  kids go to these private schools. Very expensive,   the highest level of education. He was one of  those people. He uh was very intelligent at school  

but despite that and also his siblings were very  successful. He had one sister who was a barrister   and a brother who was a dentist. They were older  than him but this kid he just constantly got into   trouble with delinquent since he was a kid from  getting into fights at school, got into drugs  

uh he was actually there for the alleged murder  of his best friend who he stabbed after he became   really high on drugs. They were arguing about this  drug exchange. They used to throw raves so it was   all related to that. So the point, the reason i'm  bringing him up is he is another exceptional case  

where there wasn't any environmental factors  or clear genetic factors that I could see it   just seemed to be random. So nature versus nurture  which one is it? To really briefly summarize the   research that we know. There was a meta-analysis  of 24 different studies and they concluded that  

the variance of violence is about 50% genetic,  50% environmental so what is a meta-analysis?   People much people much cleverer than me, they  combine all these studies and mix the results   together which is much more complicated than it  sounds because the ways that you measure violence  

can be different. So some people might have like  a self-filled questionnaire. Some other pieces   of research might look at their criminal record  and they those both those methods have potential   inaccuracies for different reasons. Also the  populations they study might be different so some  

studies might look at the prison population some  might look at males only for example so to combine   all these studies is actually pretty complicated  involves a lot of statistics blah blah blah and on   top of that there have been twin studies as well  so as you might know if you have monozygotic twins  

they're 100% genetically identical so in cases  where they're sent for adoption or they grew   up in different environments which is rare but it  does happen, you can measure things like violence   so you know how much is afforded to genetic  factors. You could also do dizygotic twin studies  

where they're non-identical twins and have 50% of  the same genetic makeup basically those studies   have revealed pretty much the same thing. So  everybody agrees that it's about 50% genetics,   50% environment so it's both nature and  nurture. I don't think what i'm telling you  

is groundbreaking, I think most people know this  anyway. So let's look at some of the environmental   factors i've covered some of this in a previous  video called why people offend. So in terms of   environmental factors, the one that cannot be  overstated I think is one of the most salient,  

is having criminogenic peers. So if you grow up  in say like a gang or surrounded by gangs or even   family members who are committing crimes then you  model what you see right? you think that offending   is the norm uh your moral boundaries might be a  bit warped or you might feel peer pressure. You  

might do things like shoplift or get into fights  uh just to look cool just to fit in with gang. So   if you lived in the ghettos of America or the  favelas of Brazil or like some of the rougher   estates in south London, i'm sure that's more  likely to happen than other posher leafy suburbs.  

Poverty is another big factor. So if you grow  up in an area where there are not educational   opportunities and you know there's very few  legitimate ways of making a decent living,   then you're going to be more easily primed to turn  towards crime. Obviously there are exceptions. I'm  

talking in a general sense. I suppose just general  parental boundaries and parental influences   help in terms of socializing people children so  that they have this kind of moral compass. Other   factors uh i've mentioned these before from my  other patients are things like being the victim  

of physical abuse, witnessing domestic violence.  So if you're a child and you witness your parents   probably most commonly your father commit violence  regularly then you model that behavior as a way   of like conflict resolution or if you're the  victim of abuse you might build up all this  

like potential anger and frustration that you  discharge when you're big enough and you might   feel that it's normal for relationships romantic  family or friendships even to have this power   dynamic where somebody has to be the abuser and  somebody has to be the victim and also personality  

factors so if you're paranoid for example  because you grow up in violence then you're more   likely to kind of strike preemptively if somebody  looks at you the wrong way for example. Drugs and   substances in general alcohol included is also  a huge factor. So there's lots of different  

mechanisms for example if you have the opportunity  to be a drug dealer because you go up around gangs   then it's a very attractive way of making a living  especially if you live in a really deprived area   where at best you might get minimum  wage. Drug dealers can make you know  

thousands of pounds per night or per week it's  a very attractive business model and especially   if you stick to the first rule of drug dealing  which is don't get high of your own supply   then you can make huge amounts of money. If  you're careful um sorry that's my hamster or  

the other rules of drug dealing which is no  income tax no vat no money backs no guarantee   and in terms of other types of mechanisms.  There's disinhibition so people who use substances   are more likely to be irritable, aggressive  and they don't think through the consequences  

of their actions. I'm sure many of you watching  this have been intoxicated. I'm sure you know   what you're talking about, like that time you  did that thing with your work colleague um   and also addiction so people who are addicted feel  this huge craving they feel they need to go out  

and make money it's no, it's no secret to know  that heroin addicts for example crack addicts   they go around commit robberies and burglaries  etc etc this is all fairly obvious stuff and then   there's my area of expertise which is mental  illness and personality factors. So I already  

told you that story about the young woman the  tragic case where she killed her two-year-old   nephew. So that was driven by mental illness. The  other one i'll tell you about is Andrea Yates. I   mentioned her quite a lot. I've done videos on  her just because the case I think is fascinating  

and you should go check out my videos. So she  also was suffering from psychotic delusions and   she killed five of her own children in 2001 in  Houston really sad case, really interesting from   the perspective of a forensic psychiatrist that's  delusions hallucinations which is the other common  

symptom schizophrenia. I talked about this  in I think my hearing voices part two video   so there was this woman who had these  hallucinations, hearing the voice of   Drake the singer rapper and she was in London.  She believed that when he came on tour that she  

was destined to meet him and he was whispering  into her ears that she was a princess that she   was swapped at birth and that she had this mission  where she had to swap cars with another woman. So   she went out with a machete, threatened a random  stranger, stole her car. That person called the  

police she was arrested so i'm just giving you  an example of how specific psychiatric symptoms,   namely hallucinations, can lead to offending. That  is an environmental risk factor and then there's   just general personality factors not uh associated  with mental illness. So i've already talked about  

being paranoid, being impulsive obviously  is a big one and also just having sort of   different social values to the rest of the  public. So let's talk briefly about the genetics   because we've talked a lot about the environmental  factors and I think the environmental factors are  

quite obvious, easy to understand. So in terms of  genetics there's lots of clusters of genes and i'm   not going to tell you about them all because to  be frank it's a little bit boring and i'm a really   busy man. I've recently got um I was fortunate  enough to get an email from a Nigerian prince  

and i'm going to inherit all his money so  I have to get on with this video because I   need to send him my bank account details. So what  i'm going to tell you about is the warrior gene,   so monoamine oxidase inhibitor is a type of enzyme  and it breaks down monoamine oxidases which are  

neurotransmitters like serotonin which deals with  impulse control or dopamine which deals with mood   motivation, arousal and reward and also  noradrenaline which helps with our flight   or flight response. So if you've got a deficiency  of this monoamine oxidase then you don't have the  

enzyme that breaks down these neurotransmitters so  they build up in your brain and we know that they   lead to aggression so mutant mice for example that  have a defect in this gene that have more of those   neurotransmitters are more aggressive to other  mice. So mutant aggressive mice clearly this is  

the marvel action film that we're just dying to  see and also similarly in a study of American   boys from the age of 7 to 12 they found out that  the ones that have behavioral issues at school   also have higher levels of abnormal enzyme that  i'm talking about. Although there often has to  

be other factors like problems at home as I said  before there are lots of other gene clusters um   that's probably the most famous one. Another one  I like to mention is called dat1 d81 as in oh I   want that one. So before I conclude this video,  I want to quickly introduce you to this channel.  

My name is Dr Sohom das. I'm a Consultant Forensic  Psychiatrist. I assess mentally disordered   offenders in courts and prisons and secure  psychiatric units. This channel is all mines,   I dissect a whole range of issues related to  mental health and offending. I look at individual  

diagnoses, I look at real true crime high  profile cases giving you my own expert insight.   I talk about my own cases occasionally although  I anonymize them so I don't get in trouble. I   interview ex-patients. What i'm trying to  say is there's something for everybody on  

this channel. If you're a regular viewer you will  know that i'm speaking at CrimeCon which is a huge   crime convention coming over to London for the  first time. I'll be giving a talk on real life   cases i've seen people that have killed their own  family members. It's going to be fascinating. You  

have to come. If you are coming use my code PSYCH  for 10% off your ticket because I got you homie.   Also i'm releasing a book in spring of 2022.  It's going to be called In Two Minds. It's kind   of autobiographical memoirs of my job and more  about my personal life. Go check it out. Okay  

just to end i'm going to tell you about some  theories, some social theories and these kind   of overlap. I have to say, some of them seem a bit  obvious and because they overlap i'm not sure how   helpful they all are but i'm just telling you what  I know so the first one is risk versus benefit and  

this is basically that everybody generally  makes sensible decisions for their lives   in their context. So whereas the average person  like you and me might not commit an armed robbery   if you're in a certain circumstance where you  really need money you've got the criminogenic  

peers, you've got access to weapons, for you the  risk versus benefit might be worth it and maybe   certainly for some people I've worked with in  forensic psychiatry they don't really care about   jail. They're kind of built for prison they go  there they have friends and family that are there  

and it's not such a big deal for them so  for them and their life is so co-chaotic and   horrible on the outside that actually for  them the risk versus benefit is worth it.   Then there's the strain theory which the theory  is that everybody kind of wants the same thing in  

life which is to be successful for some stability  uh for um financial stability but some people   because they're environments like poverty, no  role models they're so stressed that they're   willing to take shortcuts so to me it's not that  different from the risk versus benefits but it is  

a separate theory. So there's another one  called the social control theory which I   have to say is my favorite theory which is this  is, that crime is fun everybody wants to do it   inherently and everyone's capable of doing it but  we have these hurdles, we have these blockades in  

doing it and they can be external like having  sort of strict parental boundaries or living in   an environment where that behavior is unacceptable  or internal like your own empathy your own morals   and your own self-esteem and because of  those things you don't commit those crimes  

because the average person would not if they had  an opportunity to would not commit a crime. So for   example, i'm sure we've all been in a situation we  could have easily stolen the chocolate bar but we   didn't although I know that you did you stole the  snickers when you're 15 years old anyway that has  

come to the end of my channel. The only thing I  have to say left is please subscribe not only does   it help me out immeasurably, but if you don't  I will tell the police about what happens when   that snickers bar when you're 15 years old i'm not  kidding. Okay all that remains for me to tell you  

to stay euthymic and please whatever happens  do not forget, do not forget, i love you.