announcer: from our studios in new york city, this is "charlie rose." charlie: tonight, our focus will be on brain science and society.

we have an examination of social issues with neurological bases and broad social logical effects. tonight, we consider aggression, and the social application of violence. we live in an aggressive world. we are routinely confronted with violence in the form of murder war, genocide. but aggression can protect us from threats to our safety. problems arise when aggression is taken too far and becomes violence. neuroscientists are working with the transmitters that produce aggressive impulses. a remarkable group of scientists dedicated to unraveling the mysteries of aggression are here.

they are david anderson of the california institute of technology, richard remley of the university of montreal, and adrian raine of the university of pennsylvania, and once again, my cohost, dr. eric kendell. he is a nobel laureate, a professor at columbia university, and a howard hughes medical investigator. i am pleased to have all of them here. eric: wonderful to have you here. this is our third series. in the first series, we dealt with the normal brain. in the second series, we considered abnormalities schizophrenia, depression,

parkinson's, alzheimer's. now we are considering the brain in society. here we are going to consider a number of issues, gender identity, sports induced concussions, brain science, and the criminal justice system. green the criminal justice system. today we are going to consider brain science and aggression and the social amplification of violence. when you and i talked about this particular series and aggression, we knew this was an important topic and we've known it since the beginning of time. cain killing abel. it was not clear that today this would be an even more important topic. where ever you go, when you pick up a newspaper or listen to a news program, you see one episode or another of aggression. sexual assault in the military. bullying in school.

genocide in iraq and syria. outbursts of anti-semitism. shooting a guard in front of the synagogue. the list goes on. when you look at the whole picture, notably nationally, but internationally, you see that this is one of the most -- not in only nationally but internationally, you see that this is one of the most important problems facing us all, and president obama appreciated this when he called for an international summit to in discuss how to handle it. we might be helpful to society in this way. we are going to consider a number of issues that relate to aggression in an important way. we are going to begin by considering the biology of a aggression and how it often focuses on sexuality. we are going to consider the

development of aggression, how kids first start to be aggressive. we are going to learn about the response to aggression, which is not necessarily uniform, and a fascinatingly, how aggression is amplified, how people who are bystandards get recruited and often get enthusiastically involved in aggression. we are going to speak about aggression in people. there are various kinds, impulsive and meditative, and we are going to hear about them. all of these are going to come back to separate brain regions. four regions are especially important. the prefrontal cortex is very much involved in executive decision-making and character formation. the prefrontal cortex d

deformation can often lead to aggression. the hypothalamus has many functions, but we are going to focus in particular on its role in aggression and sexuality. in in aggression and sexuality. we have on this program, as you pointed out, five fantastic people. we have david anderson, who i and have known for a long time, and who pioneered a study on aggression and its relation to sexuality. in we have richard tremblay, who is interested in the development of aggression. johan has spent a career studying how victims respond to

aggression. we have a psychiatrist like myself, but competent, who is interested in psychiatric interests. we have adrian, him himwho is interested in premeditated aggr ession. we have not only an extremely important topic, perhaps the most important topic confronting all of us today, but we couldn't have a better group of people discussing it. charlie: let's begin with david anderson and understanding the biology of aggression. david: we are basic neuroscientists in my lab. we see aggression throughout the animal kingdom. how is that hardwired into the brain? where is aggression in the and brain? we have studied this problem in flies and mice, and we are particularly interested in the parts of the brain that control

aggression and those that control mating or sexual behavior. as you know, mating and aggression are closely related behaviors. in nature, you often find that aggression is at its highest when animals are mating, and these behaviors reinforce each other. but at the same time, they are mutually exclusive. a male will direct mating toward a female of the species but aggression toward a male. how can these behaviors be mutually exclusive but also reinforce each other in some way? so, we have begun by trying to pinpoint the neurons that control aggressive behavior. we started by looking in an in ancient region of the brain, the hypothalamus. we began by trying to measure the electrical activity of cells that were active during aggression or mating in a tiny region of the hypothalamus, and we found something quite surprising.

within this very small region of the brain, we found a mixture of neurons, some of which were turned on when the animals were fighting -- some -- mixture of neurons, some of which were turned on when the animals were fighting, some when they were mating, someone they were fighting and meeting. there was an overlap. we began by using very modern techniques called opti-genetics to activate and inhibit these neurons. an we can turn them on and off within a time resolution of milliseconds. i am going to show you a video of what happens to a male mouse when you activate these neurons

of aggression. some of your viewers might find the images disturbing. what we are doing does not hurt a mouse and these protocols have been approved by our animal use and care committee and approved by the nih. so, we can actually trigger the mouse to attack a rubber glove. if there were another mouse there, he would attack the other mouse as well. then we wanted to ask if these neurons were necessary. mice will naturally fight each other. if you introduce an intruder mouse into a cage where a male mouse lives, very likely, the resident will be aggressive. he does not like another male

mouse in his territory. so, can we turn these neurons off? mice are fighting naturally. when the light comes on, we inhibit the neurons. we will show you that again in slow motion. the mice are fighting. the light comes on. we stop the mice dead in their tracks. charlie: i don't understand how the neurons know how to respond to light. david: we inject a protein that turns the neuron on only when light activates the channel. so, we can convert these neurons into light-sensitive neurons. eric: there are two types, those that can be activated, and those

that can he shut off, and you can stimulate either. david: we found that low intensity stimulation would promote mounting behavior. the mouse would try to mount any other mouse he was with, male or female. we could actually switch the behavior of the same animal from attempted mounting to a mixture of mounting and attack to attack just by increasing the intensity of light. that tells us that in this tiny region of the brain, there is a mixture of neurons that are controlling both the mating instinct and the fighting instinct, and perhaps that will account, or may account, for the tensions between the sex drive and the aggression drive. charlie: extraordinary.

eric: it also explains why aggression can lead to sexual aggression. extraordinary findings. charlie: you have some information about how children become predisposed to violence. richard: we have been following thousands of children from birth to adulthood, and we have been trying to find, at what time do children learn to aggress. what we discovered is the children start fairly early in life. they use physical aggression as soon as from motor control they can hit, kick, and bite. charlie: so as soon as their brain learns to control their limbs and they can to aggressive things. eric: but they do not learn to become aggressive. they are instinctively aggressive.

that is an amazing finding. >> it's relatively minor aggression. it is a tough world when you are a two-year-old, and the frequency of physical aggression increases tremendously -- charlie: high velocity between 1-4. richard: the peak is between three and four years of age, and then it decreases toward adulthood. so humans are worst between three and four years of age. that is the worst time as far as being victimized by your peers. however, there are important differences among children. there is a sex difference.

girls learn much more quickly than than boys not to aggress. this is partly related to the fact that girls will use indirect aggression. when you don't like someone, you get others to act for you. girls learn that much more quickly than boys. there are differences among boys. about 20% use aggression very rarely. 4% use physical aggression very frequently. we call them chronic aggressive. chronic aggressive, over time, are the ones who during adolescence are chronically aggressive. but it's only 4% of males. so, if we think about what are

the factors going on here, what are the environmental and genetic factors going on, what we have been able to observe by using twins -- so we got one set of twins that have the same genetic endowment, and we used fraternal twins who are similar like brothers and sisters, they share 50% of their genes, what we see is that the identical twins are much more similar in terms of physical aggression than the fraternal twins. this is a good indication that there are important differences. it appears it is about 50

% in terms of explanation of frequency of physical aggression comes from genetic endowment 50% from environmental endowment. from the brain development perspective, we have been looking at brain imaging of serotonin synthesis in the prefrontal lobes, and what we observed is that the chronically aggressive have problems in terms of serotonin synthesis. so, these are the frontal lobes, and there are serotonin synthesis deficits in chronically aggressive children. so, it appears that genetic and early environmental factors are

involved in our ability to control our physical aggression, and this is related to brain development. charlie: so the long-term outcomes of children from chronic, physical aggression. richard: children that are chronically physically aggressive will fail in school will be rejected by their peers. they will use and abuse drugs during adolescence. juvenile delinquency criminality during adulthood and of course they have problems integrating in the workforce and they tend to become parents who will have aggressive children because they have created an environment where you

cannot learn to control your aggression. charlie: can we help them? richard: yes, we have shown with a randomized controlled trial that if we do intensive interventions, preventative interventions with aggressive children in kindergarten, we can see that in the long run they have fewer problems in school, they finish high school, they have fewer problems with drugs and alcohol during adolescence and less criminality in adulthood. charlie: things like daycare can reduce the risk. richard: yes, daycare for children whose parents have low education reduces the risk of chronic physical aggression later on.

eric: what i find interesting about this is that these kids are not being treated with drugs. they are being treated with social interventions like psychotherapy. it shows how in certain instances, psychotherapeutic intervention can be extremely beneficial. what you are describing is one of the most horrible symptoms you can have in life. everything one does is bad. charlie: if we look at the most aggressive people on the planet, if we take them back to childhood, will we find evidence of the things we are talking about? richard: it depends on the type of aggression. since we have all been aggressive early on and we have learned not to aggress from our environment, those who are most

aggressive early on are most likely to have aggression problems later on, but we have all been aggressive early on and the environment later on is an important determinant. it's easy to see why some adults who appear to have no problem will suddenly become aggressive. eric: the social amplification of aggression, people sitting around, not being participants in the aggression, can easily be recruited into it. it's a very fragile safety net we have. charlie: we go now to the response of the victims. johanna, help us understand this. johanna: a negative response to

trauma, violence, for example, is to become violent. children who were abused are at a higher risk of becoming abusive later in life. similarly, we see that groups who have experienced depression of violence develop a mentality of revenge to defend themselves against future violence, so a cycle appears there is well. that is only one response to trauma. there is a more positive form. some resilient individuals can go through positive changes after the experience of trauma. one of these positive changes

can be the idea that you want to prevent others from suffering in the way yourself or your group has in the past. for example, people who have experienced traumatic events are more likely to want to help victims of a natural disaster. in studies on police officers and mental health professionals who themselves had had adverse experiences, they are assisting others now in their professions and are shown to thrive more in their work and be more engaged in their work. there are many examples of cases where survivors of violence want to do something to change the cycles of violence. we see this also among survivors of genocide, who have the idea that we need to prevent genocide from happening ever again to

anyone else. we see examples of holocaust survivors who are active to stop the genocide in darfur or engaged in antiwar protests or civil rights movements. it is not just survivors who show this kind of response. this can also be members of the social group to identify with their groups collective experience and become particularly motivated to prevent violence in the present. charlie: so you're suggesting there are different ways of coping and responding to trauma. johanna: exactly, but both basically restore a sense of agency, sense of control that was lost in the violent experience. human beings have a need to restore this shattered sense of agency and control.

one way to do this is to show dominance and aggression. the other is to prevent violence from occurring. both have a kind of positive effect. eric: in the jewish community, holocaust survivor elie weisel has been instrumental in setting up the holocaust memorial in washington, but has also interfered in a number of genocide situations to protect the people being attacked, even though that had nothing to do with his initial experience. very much like what you are saying. johanna: and this social coping mechanism as a response to trauma also gives survivors a sense of meaning that was lost during the traumatic experience. it restores a sense of meaning

and the idea that i have not suffered in vain. i can contribute to preventing violence in the future. we know as a work of holocaust survivor victor franco, who survived auschwitz, that maintaining a sense of meaning is essential for coping with the traumatic experience. charlie: do we understand the factors that make someone more likely to be altruistic? johanna: we do not yet understand what leads to the prosocial path instead of the violent past. exposure to role models or

social support are part of it. i have the idea that if you recognize the fact that your experiences of victimization and trauma are similar to what others experience, that sense of similarity can contribute to the more prosocial path, where if people think their experiences are unique or distinct, that no one else has ever suffered in this way, that makes violence or destructive responses more likely. charlie: let's talk about how this is related to mental illness. emil: a lot of people think aggression is more prevalent in people with mental illness and the fact is that mental illness on its own does not increase the

rate of aggression. it is more likely to occur in individuals with histories of substance abuse and other factors. everyone gets very concerned when mass shootings happened and those sort of things. this person must be psychotic, mentally unfit. those are individualized situations. you look at large studies and it does not pan out. there are multiple forms of aggressions. there are socially sanctioned forms of aggressions, there are medically related aggressions. the two big ones really are impulsive aggression and premeditated aggression. impulsive aggression is aggression that is not exactly spontaneous but people get -- perceive a threat or frustration and their threshold to blow up is very low. they will blow up and display a temper tantrum or physical aggression. premeditated aggression is already thought through.

they have planned it out. the people who do that are more likely to be psychopaths. the number of psychopaths, maybe 1% of the population. people having mental explosive disorder which is the disorder of impulsive aggression is more like 3%, 5%, 6%. those important distinctions to put forth because we have an idea about how to treat impulsive aggression and we're not quite sure how to treat premeditated aggression. charlie: what do we see at the neurobiological level? emil: what we see in people with aggression is similar to what we hear at this table. dr. tremblay talked about 4% of boys being chronically aggressive. it is about how many ideas you have out there. about 4%, 5%. these endings biologically

problems with serotonin function. usually it is diminished. with the evidence of heightened other neurotransmitters which facilitate aggression. in terms of systems, we see problems of the frontal area of the brain. when we present to these individuals pictures of individuals who were angry or threatening, one part of the brain overacted at that stimulus compared to healthy volunteers. an important thing going along with this is serotonin has to do with the tendency to be aggressive but what makes you aggressive in the here and now has to do with how you interpret social singals. people who are aggressive tend to have problems with social information processing. they don't take in enough information of what is going on and they make a hostile entrance into what the other person is

doing. you have a situation where the threshold may be high or low and where you're coming into the day is that you are primed to think that somebody brushes up against you or looks at you funny is threatening or frustrating. you have the serotonin system and the frontal lobes aren't working well. you have his high accelerator and you'll have a crash. eric: when charlie and i did a program on depression, one of the key things that emerges is the depression is designed to increase the level of serotonin. is there an increased incidents in this kind of depression? emil: not necessarily. early studies i did were interesting in that we saw this problem in individuals that did not have a primary mood disorder. what we think is going on is that their brain systems are involved in activations and they

are not working well. that is the arousal that is going on. the low serotonin when you are suicidal. charlie: adrian, let's talk about people cannot control their impulses. adrian: we have been talking about people in hospital context. we work with people at the street level, people who are violent psychopaths, even killers. charlie: what does psychopath mean? adrian: they lack conscious, remorse, guilt. because of the lack of emotional feelings, there are no barriers so they do outrageous things. emil: you have the antisocial lifestyle, which is doing horrible things to other people. adrian: we have in starting their brains to look to see what parts of the brain may not be

working right but what parts of the brain may be physically different. what we find in normal people of course is that their prefrontal cortex is working well as you see there in the green. if we can have the next slide, this is where we see murderers. we see them impulsive, they don't plan their murders. they are very hot-blooded in terms of their homicide. what we see on the left is poor functioning in the frontal region of the brain. why is it that part of the brain came predisposed to aggression? it is a part of a brain involved in checking on impulsive behavior. we all get angry. what stops us from lashing out is we have a good frontal cortex to regulate and control our behavior. what about the cold-blooded murderers? when we brain scan them, they

have pretty good frontal functioning. in a way, it makes sense because these are killers who premeditate their homicide. they are planning ahead. the interesting question becomes, what is it that is producing them to be violent in a predatory fashion? let's turn to the next slide where we look at another brain region. this is the amygdala on the left. what we find when we study cold-blooded offenders psychopaths, they have a shrinkage in the amygdala. it is reduced in size by 18%. on the right, the areas that are actually physically deformed. the amygdala is very important in generating emotions. a shrinkage will reduce fear.

what stops us from breaking the law? when we are threatened with the punishments we would get if we were caught. when you have this impairment that normally produces this fear that stops us, you are more likely to commit offenses in a cold-blooded fashion. there is more to it than that. there is yet another brain region called the ventral striatum. you can see there is greater activity in psychopaths when they are anticipating rewards. psychopaths are reward driven. they want the goods. just like an addiction. charlie: it is a stimulation to the brain? adrian: the idea is the brain that gets hopped up on reward is

firing a lot more. maybe that is why they are more likely to pursue rewards and games that they want. they have a drive to do it and they don't have the emotional amygdala to hold them back, to give them not fear that would normally resolved. eric: this is a spectacular series we are discussing. when i was a student, these techniques were not available and you had little insight into what was going on in the living brain. we now have insight into the biological strands of different kinds of aggressive systems. we can see this is the beginning of how much we will learn. different categories, impulsive versus premeditated, different categories. charlie: the question is, can you look at imaging and decide who is most likely to be

aggressively violent? adrian: it is a great question and we do get close on who may be more likely to be violent in the future. my colleagues brain scanned males in the community. those with a small volume to the amygdala, they were four times more likely to commit a violent act in the next three years. that is a prediction over and above prior history to violence. it is not a perfect prediction but we are beginning to get value using brain imaging to try and understand who are at risk for becoming the next generation of future offenders. charlie: are we seeing this research used in criminal trials? adrian: the question is that if psychopaths -- first of all,

what is causing the shrinkage? it could be genetic, it could be how the brain works. we also know trauma reduces the size of the amygdala in children. neglect reduces the size. for whatever reason. i don't think psychopaths have to be born with an amygdala three sizes too small. if the brain impairment predisposes them, it raises the odds of them doing the terrible things, the fascinating question is to what extent do we hold them fully responsible? eric: we will return to this. this is not dna evidence. this is not like saying, i'm responsible, david is not definitively. that is imperfect in front of the law. i think as techniques get better and we see that not only the amygdala but other areas associated with abnormalities,

it is unrelated, then we will be in a better position. charlie: are there cases where it is not just within an individual but the violence becomes contagious within a society or group? johanna: when we look at cases of genocide, we can see that this often happens in the context, on a societal level many of the processes of what we see our normal processes that amplify violence. genocide and mass atrocities occur in the context of drastic societal transitions where there has been for example, war, sudden economic deterioration, other factors that lead people to experience a loss of control and safety. human beings want to restore

this need for safety or satisfy this need for safety and control. one way of doing that is defined as scapegoat, to say that if we get rid of this group or restrict their rights, this not only explains our problems that we are facing but it will also solve the problems. scapegoating is a common root cause of this contagion of violence. there are several examples of this when we look at genocide. for example, prior to the holocaust, germany had lost the first world war and had to pay repperations with a contributor with a large economic crisis. in this context where people were experiencing sudden drastic transitions and extreme poverty, people blamed the jews for what was happening, which many people

bought as a simple solution to the problem. that contributed to the cycle. >> i was one of the jews involved. i was in vienna in 1938 when hitler marched in. the next day, i met a classmate and he said, i am never to see to you again. my parents told me that. you could see the people and you ask yourself why. there are many reasons that contribute to this. one is in the medical school within three days, they fired 50% of the faculty because they were jewish. if you were an assistant professor that was not jewish, you could move up so maybe anti-semitism is not that bad. others because parents told them not to do it. if they do not follow along, they will be punished. there are many reasons of being told that.

innocent people -- previously innocent people can be pulled and because of a number of circumstances. it is quite amazing. charlie: how long after that did you decide you had to get out of austria? eric: my mother had the good sense to get us out. we got out about a year later. charlie: always i'm interested in terms of where all of this is going. where are we headed in terms of the kinds of things we're understanding about aggression? are we headed to understanding -- we can figure out ways to reduce violence, to lessen violence. if that is true, what gets us there? eric: i think what would be a major change, and i think obama is aware of that, is to try to prevent the social amplification of violence, to prevent the

people being pulled along from joining that. this feeling is one of the reasons they go along is many parts of the world that are not democratic enough and they're not completely satisfied with their lives so they're willing to join some other force that makes it more attractive. he feels spreading democracy to the world -- how to prevent these borderline people from being affected by this. isis is a great example. they pull people and with no previous commitment towards them at all. they pull people along. they show the movies, alternate things in order to bring them in to the fold. charlie: it is stunning to me that somehow they have romanticized violence. eric: absolutely. charlie: young people -- eric: think it is a wonderful thing to be doing. shocking.

johanna: these destructive ideologies from the outside, it is clear they are destructive, scapegoating. from inside, at the time, -- within the society where they are being promoted, those are following these ideologies, they do not think this is a destructive, violent ideology. it often appears to be a constructive or moral or positive ideology. it is because it will help solve the problem, get your group out of the difficulties it is facing. eric: one of the reasons i'm so pleased with this program now is because i think significant investment in scholarship on this level can be extremely productive. this is one of the directions it

clearly has to go. david: one of the things we need to do is decrease aggression in general. it is clear a chance of a child being victimized increases chances of aggression down the road. we really need more comprehensive approaches and we have to be thinking about the different forms of aggression. psychopaths that require a different approach. richard: we have heard a lot about social factors. biology at the basic ultimate level, what you're about the influence of genes, this is something we can study in the laboratory and animal models. we find the genes that predispose aggression and they have the same effect on aggression in mice, rats, cats even evidence that people that

self-report as being aggressive showed higher levels of these aggressions in their system. charlie: therefore? is there a height in emphasis on developing drugs for this? emil: no. you have to have a clinical trial. if people get more aggressive during the trial, because of a placebo, that is a legal liability. you have another story about that. you have a problem with the nih not really wanting to fund this kind of work. eric: it is a historical problem. david: the nih does not want to fund research on aggression. it is a socially, politically

charged issue. charlie: because? david: i think there is concern about learning more about the biological basis of aggression that information might be misused to stigmatize people as having a predisposition for violence. the fact is science has been misused in many areas. the nazis misused genetics terribly in their persecution of the jews but that does not mean we should not learn more about the fundamental biology of aggression. charlie: it is significant do this research because it will accomplish what result? emil: a deeper understanding of the basic biology effectively to the drugs that could help individuals with a predisposition to violence. it will tell us what not to do the violent individuals.

in flies and mice, social isolation causes an extreme increase in violent behavior. what do we do with violent criminals in jail? we put them in solitary confinement. exactly the opposite of what we should be doing. eric: i think psychotherapeutic approaches, not necessarily analytically-based, can be very helpful. helping parents who have been aggressive on themselves control themselves when they see a child in a more benign fashion. that could be very easy. charlie: one generation passing it to another. adrian: biology is not destiny. we can change the environment to change the brain to change criminal behavior. david: you can also change biology. adrian: absolutely. eric: psychotherapeutic

intervention changes the brain. adrian: go back to early childhood. we did enrichment enhancing the environment of three-year-old children to give them better nutrition, more exercise, and cognitive stimulation for two years. at age 11, the brains were more mature. at age 23, there was a reduction in criminal behavior by 34%. enrich the early environment that can up regulate the brain and reduce criminal behavior. charlie: is that what you mean by change the biology? david: partly. i also mean medication or psychotherapy. eric: trying find out how we can constrain the social applications, how we can take neutral bystanders and encourage them not to join. i think you'll get a telephone call from washington tomorrow.

they will want you to help them. this is the kind of thinking they need. emil: another area this touches on is violence toward women. the sexual violence towards women is a serious problem that is associated with conflict situations for example, the high level of rape in the war in eastern congo, sexual assault in the military. this is a serious problem. some of our studies might shed light on the reasons for this. the fact that circuitry for sexual behavior and aggressive behavior is so closely intermingled in the brain and that if you have men that are engaging in aggressive behavior participating in a war with military training, this may build up an arousal system through hormone changes that amps up the circuitry for violence and sexual behavior and that can be released both through more violence toward

other men and also through sexual aggression towards women. this is a dimension. one sees this in cases of domestic violence and spousal abuse. this is a huge issue that needs intervention, deeper understanding of both the biology and sociology. charlie: are we seeing that a lot of social and sexual violence is biological? david: there is an underlying biological drive which is modulated by environments, social factors, substance abuse, but there is the biological substrate that links these drives together in a very tight way. what will we do next time? eric: we will speak about gender, how gender determines

differences in intellectual functioning, how difficulty with certain aspects of identification with female sexuality interferes with mothering. we will speak about the differences between men and women on a lot of levels including things that are unique to women. charlie: see you next time. thank you for joining us. ♪

>> the following is a paid program. >> the following is a paid advertisement for the new face of time life, starvista entertainment. ♪ welcome to my world ♪ >> these are songs we will always remember.