dear professor barkley members of the birgit and siena olson foundation colleagues ladies and gentlemen my name is yani nunstrum and as the head of institute i wish to welcome you to the university of gothenburg to the sol gransk academy where the institute of neuroscience and physiology and the gilberry neuropsychiatry center is located i am deeply honored to be here today uh to introduce the eighth perigee tulsa lecture and i think we're all very much looking forward to this inspiring afternoon listening to professor barkley and as a part of her lost will and testament birkie tulson who was married to stan aulson the founder of the styana's fair made a significant and highly appreciated donation to create the birgit and stan ulson foundation the foundation contributes to the financing of the yield by neuropsychiatry center at our institute led by professor christopher yilvari the yield banner psychiatry center jgnc was founded in 2010 and features a highly successful group of approximately 75 researchers active in research on autism adhd and rexella nervosa and other essence disorders since 2011 the gnc has been organizing the birgit tools and lectures the lecture is given by an international authority in the field of one of the centre's preferred research areas henriksen nerosa adhd or autism and today i'm deeply honored to introduce professor russell barkley who will give the eighth birgitolson lecture entitled the second attention disorder sluggish cognitive tempo versus adhd professor rasa barkley is a clinical professor of psychiatry at the virginia treatment center for children at virginia commonwealth university medical center in richmond usa he's a world leading expert in adhd and related disorders professor barkley is a clinical scientist educator and practitioner who has authored co-authored and co-edited 20 books and clinical manuals he's also one of the most cited researchers in the field of adhd and has published more than 200 scientific papers and book chapters on the fields of adhd and related related his research has been both due to the nature and the assessment and treatment of adhd and he has appeared on many u.s nationally televised programs to discuss topics pertaining to adhd he has also received numerous prestigious awards over his career for his work in adhd and related disorders please join me in warmly welcoming professor russell barkley we are deeply honored to have you here today [Applause] thank you what a pleasure thank you good afternoon wonderful thank you i wish my mother was alive to hear this and we're starting on time which means this isn't italy or spain is it always a pleasure to come here so i i first want to begin by thanking uh dr joel berg and uh eva dr bilstead for the invitation to come and speak to you it's quite an honor to be invited to give this uh memorial lecture and uh i take it very seriously so it's it's truly a privilege and to be back in sweden probably my fifth or sixth trip here which is uh wonderful today i want to speak with you about a condition that has only recently begun to receive the research attention that it deserves even though it was first identified at least in 1984 and some would say even as early as 1798 but serious attention was given to it only within the past decade now before i do at least in the united states as chris knows it's commonplace for us to share our sources of financial support for the previous year so that the audience can evaluate whether there's any potential financial conflicts of interest with this particular topic so although i am semi-retired and spending more time with my grandchildren obviously i continue to work and teach and write uh as well so let me begin with the topic of interest today and that is have we discovered another attention disorder that has gone unrecognized or more commonly misdiagnosed as a type of adhd and that is the question we're going to try to answer today from the standpoint of evidence of science and so my objective is to of course educate you briefly about the history of sluggish cognitive tempo i will use the term sct frequently to refer to this condition and the emergence of research in that history and then i'd like to go over the available evidence within the various fields that have accumulated so far just in contrast there's less than 100 research papers on sct there's more than 50 000 on adhd so that just gives you some idea of the relatively understudied nature of this condition i hope this talk changes that and that more people decide to investigate this other attention disorder i'm going to briefly talk about some of the theories with regard to the underlying nature of the condition though that as you will see remains hypothetical and then i'll talk briefly about what we know about management or can infer about management from from what we know so just a brief history uh you may not realize it but the first reference to adhd goes back to 1775 when in one of the first textbooks in medicine was published in germany by melchior adam weikert and there is a chapter in there called disorders of attention and in it is a description of what today we would recognize as the combined presentation of adhd but weikert was describing just one prominent disorder of attention it was his colleague and student alexander creighton who followed up wrote a much expanded version of a medical textbook a much longer chapter on disorders of attention and now describes a second condition of low arousal low power withdrawal and lethargy that characterized this second group of individuals so that this might be the first historical reference to this other attention disorder it is of course always speculative to try to know what he was trying to describe at that time and map it onto contemporary ideas of attention disorders but we at least have to acknowledge that there's the possibility he was the first to recognize this and then the beginning of true research is 19 mid 1980s and it begins at the university of georgia with benjamin leahy karen carlson and one of their students nipper and at this time we had in the dsm-3 attention deficit disorder add but broken into two types with and without hyperactivity the distinction at the time had very little research to support it so a flurry of research studies was undertaken during that decade attempting to identify just what separated these two conditions and was it justifiable to distinguish the two types the end result of that decade or more of research was no there were few if any differences between these groups and by the time dsm-3r came around it completely eliminated this possibility and it relegated add without hyperactivity to the back of the manual referred to it as undifferentiated attention disorder and asked for more research but it was no longer officially recognized but at that time leahy and his students were looking to find new and better symptoms to include in the next edition of the dsm to identify adhd and so they generated a list of items symptoms to use in interviews and rating scales and to investigate for how well they discriminated or identified that condition it was during that research that nipper found that a set of the symptoms that they were playing with at the time did not correlate well with adhd did not seem to be useful in discriminating it recommended that they not be included in the dsm but recognize that they form their own little dimension of problems of psychopathology and he is the one who invented the term sct i will tell you i don't like it i think it's demeaning and i have written a number of editorials to my colleagues asking them to change the name to something less offensive to patients but in the meantime sct it is and that is what i will call it in this presentation though please understand that i am against this term being used further uh for this condition so nipper was the first to say i've got a set of items they're distinct from adhd they're not highly correlated with it they form their own factor in a statistical procedure called factor analysis and here it is and just gave it up to the field to do with it whatever they wanted but certainly recommended to the dsm committee that they not use these items research continued on this add with and without hyperactivity even though the dsm eliminated it and we kept coming back i was doing research at the time and those of us who continued to study the differences kept finding that while there weren't many useful distinctions between those two types of adhe we kept coming back to this subgroup of people who were quite different qualitatively from the rest of the people we were studying who had a lot of the symptoms that nipper had identified in his research and who seemed to have unique comorbidities correlates and in the case of our research we were the first to show that they did not respond well to the stimulant medications that we were testing for people with adhd research continued on this despite the dsm abandoning add with and without hyperactivity and then it sort of died off for a while after about the year 1990 to 1995 wasn't much research going on then and then dsm-4 brought the distinction back again with its types of adhd there was an inattentive type a hyperactive type and the most common is the combined type so the inattentive type is really the old add without hyperactivity brought back again this is very disconcerting because we had research that showed that this wasn't very useful but it was done anyway it was primarily done to satisfy clinicians who were complaining that they had no place to put people who had troubles with attention but did not have the other symptoms that were characteristic of classic adhd they weren't impulsive they weren't hyperactive and so what to do with them so they were given another type of adhd to use and once again researchers go back out and start looking at are there differences among these types of adhd and so we have probably hundreds of papers comparing the types and the end result of that is that it's not useful and so they were eliminated in the dsm-5 and demoted to the term presentation and that is simply meant to say that on any given day someone with adhd may have more symptoms of one dimension than the other but it was not intended to convey a concrete category of a qualitatively different group of people people could change presentations you could have preschool children who were very hyperactive but not yet inattentive being called hyperactive presentation within four years they would likely become the combined presentation as they became inattentive and then by adolescence because the hyperactivity declines very quickly in adhd would then move into the inattentive presentation so if you were growing up with adhd classic adhd you could go through all three presentations and nothing's changed about you other than on any given day some symptoms are more prominent than others so we were told to abandon all hope there are no other subtypes but a subset of those of us who were studying these groups kept coming back to the idea of let's not throw out the baby with the bath water there is a subset of people who are inattentive who we know because of our experiences with them are different let's study them outright and that is when sct began to get its own body of research uh rather than studying just adhd individuals so here is where we now stand we have an inattentive presentation we can subdivide it very nicely into children and adults who used to be in the combined presentation but have lost their hyperactivity and now are being called inattentive we should not change their name they're always going to be combined types and we should treat them accordingly there is a second group of people who are very annoying to clinicians because they are one symptom short of being in the combined type they have six inattentive five hyper active according to the dsm decision rules they are inattentive and that's how they should be called but they are just mild versions of the combined presentation and that's how they should be treated after all it is a dimensional disorder as dr gilberg has been saying for many decades we are dealing with a continuum in the population not a category and it's no surprise that some people are just one or two symptoms less than the combined presentation so let's keep them with the combined types then there is the group that has high levels of inattention very very low levels of hyperactivity almost no impulsivity and what do we do with them and this is the group that we were always singling out as showing elevations in the sct symptom dimension that nipper identified how many people is this well according to studies such as keith mcburnett at san francisco at least a third of people being called inattentive presentation probably have this other disorder maybe as many as 50 percent or more by the way just as an aside i see some of you taking pictures with your cell phones i do make my slides available you simply have to ask me i'll leave them with the gilberg center and you can get them from them as well so you don't have to take notes or pictures if you don't want to so it's this group that now commands our attention and previously we would find them by going to an adhd clinic looking for people with high inattention low hyperactivity screening them for sct symptoms and studying them accordingly the problem with that is that it immediately confounds the two disorders if you're starting with a pipeline full of adhd you're going to get a lot of overlap with adhd in your sct population so more recently within the past 10 years we've been identifying people with sct outright they don't have to be referred to an adhd center we find them in schools we find them in pediatricians offices i did a national survey of the united states and we found them that way and that's a better way to identify them to avoid the contamination or confounding that you get if you only look for adhd centers to find these children more often than not by the way they're being referred through learning disability pediatric early behavior problem clinics rather than through psychiatry and you'll see why that is in just a moment so what is this research these 90 or so papers beginning to tell us about this group of individuals in comparison to adhd have we found a new disorder this is something that i am championing i do believe we have i think we're seeing the emergence of one disorder from another just as we saw autism spring from childhood schizophrenia and bipolar disorder also from schizophrenia and adhd from mbd and ld we are witnessing the divergence of one disorder from another to try to improve clinical care and identifying more homogeneous subgroups of of our patients but what do you have to do in psychiatry to prove that lee robbins among others set forth the washington washington university in st louis as did dennis cantwell and others that if you're going to declare a new disorder you need to show that it differs from other disorders along as many of these categories dimensions areas of research as possible so this is our task today let's go through each of these let's see what we know let's compare it to adhd as the closest comparison disorder though i'll have some things to say about other disorders as well and let's see what we come up with so you're going to be the jury i'm going to be the prosecutor i'm going to present my evidence and you'll decide whether we've crossed the threshold required for a new disorder or not even if you disagree that it's not so impressive yet as a new disorder many people are arguing that it is a trans diagnostic condition which means it's something we need to study as a deficiency that it cuts across traditional psychiatric disorders and that might be a better way to think of it for the moment until we get more research because after all the term disorder implies some official recognition by the powers that be the american psychiatric association the icd committees that we have met the criteria of evidence i happen to think we have but that's just my bias and as chris knows i'm a bit of an impulsive individual anyway i like to think of it as being decisive but my relatives would say otherwise and certainly my family is part of the adhd phenotype and sadly most recently also the autism phenotype now the symptoms that best identify sct are seen here this is based upon a complete meta-analysis of all of the research that we have looking to find symptoms for this disorder so my thanks to steve becker and his colleagues for this meta-analysis these are the 16 best symptoms so we have obviously behavioral symptoms of sluggish movement slow movement we have cognitive symptoms of daydreaming staring spacey confused mental fogginess proneness to error in perceiving things so like adhd we're sort of seeing a two-dimensional disorder here one of motor symptoms and one of cognitive or attentional symptoms the problem with this list as uh steve and i communicate regularly and as he well knows uh is that four of these symptoms don't work very well and should be eliminated and those are the ones in yellow and and the reason for that is as follows first of all symptom 12 lacks motivation and especially that one is as common in adhd as it is in sct so it's not discerning it's not discriminating it's a good symptom people with sct show that a lot but it won't help you in differentiating a disorder so we don't need it here the other three symptoms are or four symptoms are symptoms of working memory and executive functioning more generally and if you were to put them into a rating scale of executive functioning and then do the appropriate factor analysis they would migrate over to a dimension known as self-organization planning and problem solving how well can you organize your mind your thoughts your behavior and your goals to accomplish what you hope to do and they no longer will load on an sct dimension so we need to get rid of them uh and i did so this is my rating scale of sct we reduced it to 14 we got rid of the overlap with executive functioning the problem is that we also found the same thing items 13 and 14 are very common in adhd children as common as they are in sct so they're not helpful and we need to get rid of them so what we wind up with are 12 symptoms that work very well at identifying these people now let's not forget that the word often has to appear in front of these systems just as it does in adhd and that's not arbitrary by the way when i talk to people it's like well where did you guys come up with that uh the fact is that statistically when you ask a population about a symptom the word often is endorsed only about two to ten percent of the time so it begins to discriminate a developmentally inappropriate behavior if you said sometimes or rarely those are very common symptoms but the minute you get to often or very often you begin to separate out what is abnormal what is a symptom what is statistically unusual in the population and we've proven that many times so don't discard the word often as just something capricious or arbitrary it actually denotes a level of inappropriateness of a behavior that we can prove in the population identifies a very small set of people and then if you require that they have multiple symptoms that occur often now you're really getting to a developmentally inappropriate condition and i emphasize this because sometimes people fall prey to the logic of the church of scientology in arguing that we're simply trying to diagnose normal children with psychiatric disorders because after all don't typical children show these behaviors from time to time so barkley and julberg and others and biederman are simply trying to create a disorder on behalf of the psychiatric drug community and help them to make their profits and so basically you're conflicted and you shouldn't be doing this and i've been accused of that many times most recently about a year and a half ago in the new york times where it was declared that barkley is trying to turn childhood daydreaming into a psychiatric disorder which of course is nothing close to the truth but then journalism isn't about the truth anymore is it so um let's begin then number one have we found a set of symptoms that is distinct from other types of psychopathology the answer is yes those are the 12. and if you analyze them in the midst of symptoms of executive functioning iq tests adhd dimensions anxiety depression psychosis they form their own independent set of symptoms they correlate more highly with each other than they do with any other type of psychopathology check we have met the first criteria we found a unique set of symptoms number two are they dimensional or categorical and how many dimensions are there looks to be one large dimension that can be usefully separated into two smaller ones but with the understanding that the two dimensions we're talking about are very highly correlated with each other and that's what we see in adhd as well it's what we see in autism it's useful to create these dimensions but don't ever think that they're independent or uncorrelated they're highly correlated indeed some studies find only one dimension but we have two and what's interesting is one is cognitive attentional that's the daydreamy dimension the spacey dimension the other is the sluggish slow-moving hypoactive dimension okay so we have some dimensions not categories they're distinct from other disorders what else can we say about them well we need to show that these dimensions correlate more highly with each other than they do with adhd symptom dimensions because some people have said you've just discovered a type of adhd not something different and so we've done that already you can see in the correlations here that the two dimensions of sct correlate with each other about 0.75 to 0.8 which is the same thing we see in adhd by the way and correlate much less with adhd symptoms though there is a moderate correlation within attention in adhd and you can see that here about .4 maybe 0.5 don't be so impressed if you square the correlation it tells you how much variance they share with each other and it's about 16 to 20 percent maybe 25 what does that mean it means most of the information in one dimension is not contained in the other disorder and that is very important in showing a new psychopathology a new attention disorder we have found these symptoms in these dimensions to exist in every form of measurement that we have studied that's also an important distinction if we only found it in teacher reports and it disappeared in parent reports we couldn't see it in classroom observations but we could see it in clinic observations this would not be reliable it would not be impressive the sct dimension has been found in every single approach to measurement used all of the ones i've already mentioned parent reports teacher reports self-reports adult reports clinic observations classroom observations same dimension shows up everywhere and it doesn't matter how you assess it in other words this is a very robust dimension of human behavior and it's not frivolous or specific to some issue of methodology or measurement the next thing we we want to see is do these factors these dimensions link up with depression anxiety other kinds of conditions because if they do then maybe this is just depression under another name or as my chairman who's an expert in hypersomnia and psychiatry said all you've done is to rename hypersomnia daytime sleepiness uh good point so we need to go about our business and see whether or not you can distinguish these things and here's a beautiful study done by my colleague just down the street joshua langberg also one of the emerging experts in this along with his colleague steve becker and others and what you're seeing here are sct symptoms relative to depression and what this shows you is that these are distinct you see the depression symptoms up at the top and they form their own cluster versus the symptoms of sct there's a little bit of overlap with the drowsy sluggish movement dimension that you might expect to overlap with depression but much much less with the cognitive attentional symptoms that you see down below so the distance between the different symptoms and clusters is a measure of how distinct they are from each other but the most important thing is that the depression symptoms form their own cluster and sct is not a form of depression this has now been demonstrated also with daytime sleepiness and with anxiety so we can safely address our critics no we're not just renaming another disorder as sct we can show how distinct they are well now we come to the issue of are there demographic differences between these people and particularly people with adhd that's the closest disorder we have to distinguish it from that's the hardest disorder to distinguish it from so what do we find well we've done national surveys of children and adults as you see here in the united states and we have a prevalence of sct if we want to create a category or a disorder like we do in dsm we have a prevalence of four to five percent depending upon uh the age but it's roughly in that area about five point four percent of adults and about four point seven percent of children have sct and how do we categorize them they had to have symptoms that occurred often for at least six months that led to impairment and placed them above the 93rd percentile of people their age how many symptoms does it take to do that three three out of the twelve symptoms will put you in the top seven percent of the us population so these are very rare symptoms in the population and it doesn't take many to begin to distinguish you from typical people so three or four depending upon which study you look at so how common is it in clinics we've only begun to look the first study done in spain says one in five children coming to a psychiatric outpatient clinic has sct if they have autism or adhd or ld that rate is considerably higher but just being referred to a clinic starts to pull out one in five children as meeting these criteria to put it another way sct is as common as adhd and as we showed in our national survey part of the rise and the diagnosis of adhd in the united states is the result of creating an inattentiveness in adhd and then putting these people in it which inflated adt from a prevalence of four to five percent to a prevalence of seven to ten percent if you take these people out of that prevalent survey the prevalence of adhd goes back to what it has always been over the last 30 to 40 years there's been no rise in adhd at all what you did as we did with autism spectrum is you broaden the definition you rolled in another disorder into it or at least something related to it and voila prevalence explodes the media gets upset the public is outraged psychiatry is criticized yet again for expanding disorders and making money for the drug companies which is very difficult to say because there's no drug for sct at the moment but uh that said that that's sort of the criticism here so what we see then is sct is a very prevalent disorder it's about one in 20 children and about the same in adults the surprising thing is that there was no change with age unlike adhd which shows a three to one male to female ratio in childhood two to one adolescents about one and a half to one by adulthood sct shows no such distinctions between age and sex it is an equal opportunity disorder and it does not decline with age from ages 5 to 92 in our survey no decline no difference whatsoever whereas in adhd there is a remarkable decline from childhood to adolescence particularly in the hyperactive dimension of the disorder and we see none of that here so we've now got several demographic differences that distinguish this condition from an adhd type disorder in addition to that we began to find something that was quite surprising we know from research done here in sweden and elsewhere that adhd is somewhat related to social disadvantage low education differences in income as well as well as greater disability within the family more psychiatric disorders more imprisonment more criminality more drug use so we were quite surprised to see that sct was worse we did find that in our results adhd is related to those things sct was even more likely to be associated with them and that was a bit surprising but i will have more to say about that when we get into what is the nature of sct so let's move on to the cognitive dimension of establishing a new disorder is there evidence of cognitive differences some not a lot yet but here's what we're finding the most reliable difference from adhd is there is no impulsivity in this disorder no evidence on testing on rating scales and so on of disinhibition if anything the last few studies that have been more rigorous have found that they're negatively correlated if you have sct you will be less impulsive than a typical person you're actually going the other way so that is known as a double dissociation in psychology and it's very important in proving a unique disorder one disorder goes one way in its correlations the other goes the opposite direction you cannot argue that they are just proxies for each other and so we have found that in terms of impulse control so sct is not an inhibitory disorder adhd is a massive disinhibitory disorder a self-regulation disorder adhd correlates with iq uh correlations run usually between about 0.3.4 uh they shear about 10 to 16 percent of their variance and they're negative the higher your adhd the lower your iq will be on average about seven to ten points lower in population studies and there's a reason for that the genes for one are actually the genes for the other and that was shown just yesterday in the largest study of dna done in psychiatry this is the genome-wide loci study in nature genetics that just appeared within the past day and what did they find in studies of 55 000 people nearly half had adhd they looked at 300 other traits within the study one of which was intelligence and they find that there is a striking negative significant correlation between the genetic loading of intelligence and the shared genetic loading with adhd so there's a reason that these two psychological traits are correlated negatively and that is that they have an underlying genetic shared genetic basis to them so with sct the relationship to iq is unreliable a few studies find it studies such as my own do not community studies don't find it so if there's a link to iq it's very small whereas in adhd it's robust it's reliable it's repeatable and just about any study that looks for it finds it and by the way there's also a developmental linkage between them people with adhd will find their iq continuing to decline the longer they have their disorder and also starting out with low iq increases the likelihood of developing adhd over the next period of follow-up so there might even be an ideological relationship between them not just a genetic relationship another finding that is emerging but not yet definitive is slow responding to tasks whether it is the perceptual motor speed task of the wechsler scales whether it's a reaction time test very simple people with sct are just reliably slow in their motor responding adhd people can be but as chris and many others know the finding in adhd is not slowness it's variability indeed marcel kensborne in the 1970s referred to adhd as vd variability disease was a semi-humorous reference of course to venereal disease but uh the the point is that what distinguishes adhd from others is not the mean score it's the standard deviation the variability of responding even on a simple reaction time task is three times greater in people with adhd than in the typical population it is such a hallmark of adhd that it is the most reliable neuropsychological finding across the entire literature if you want to pick a single laboratory measure that picks up adhd relative to everything else it's going to be a reaction time variability so sct doesn't show that the variability of sct is right in the typical narrow range they're just slow so to summarize one has slow reaction time one has highly variable reaction time due to their inattentive distractible impersistent behavior when we give batteries of attention tests these kids show up as having problems with focus of attention that is they can't quickly focus on to what is important from what is unimportant in the stimulus you're giving them that is not a characteristic of adhd adhd is a lack of persistence people with adhd don't have trouble picking up what's important they just don't care they don't respond uh and if they do respond they don't stay with the response what you're seeing is an impersistence not a focusing problem to put it very simply there's nothing wrong on the perceptual side of the brain in adhd specifically there probably is something going on on the perceptual side in sct and it appears to be this dimension that posner and merski would refer to as the focus orient aspect which we know is mediated by the posterior hemispheres particularly the parietal lobes so there may be some interesting differences here but we need a lot more research on that what about executive functioning well if you give a test battery of executive functioning to sct sometimes you get a little working memory deficits oftentimes you get nothing they're not different from other children so the working memory deficit is not reliable if you give a battery to adhd children you get a lot more deficits across measures working memory impulse control and so on but even there only about a third of kids with adhd are impaired on ef tests however if you give an executive function rating scale to people with adhd they are universally impaired above the 93rd percentile across all dimensions so according to rating scales adhd is efd with the wrong name and that of course is my opinion um but if you give a test battery as many of my colleagues like to do and you believe that testing is the face of god and the voice of god for sure which many of my colleagues also do then you're going to conclude that only a third or less of adhd people have ef deficits therefore adhd cannot be an executive disorder and that debate continues to this day in the published scientific literature there's there's one fatal flaw that my colleagues in neuropsychology overlook if not outright ignore ratings and tests have no correlation with each other the test batteries of executive functioning have absolutely no relationship to the rating scales and you might say well so much the worse for the rating scales because after all the tests are the gold standard but wait a second the rating scales cover at least six months to a year of observations by people who know you well teachers parents others the tests capture none of that the tests take about 15 minutes each they're done in an artificial clinic setting by someone you don't know uh they're largely cold cognitive informational in nature which is why they correlate with iq and they predict nothing so if predicting impairment in life is why we assess people which it is then we have shown a number of publications not just my own research team though we certainly started it that the tests predict nothing the rating scales predict everything so if you want to know if someone is impaired in school social relationships managing money raising their children holding a job driving a car give a rating scam that will predict all of those outcomes give a test battery predicts nothing but your scores on an academic achievement test at school and it won't even predict that if you covary iq so why are you giving the tests it's a question i keep asking my colleagues you're giving the worst measure possible of executive functioning you're drawing conclusions about a variety of psychiatric disorders you're making high-stakes decisions about patients whose lives depend on the scores from these test batteries as to whether they get support accommodations disability determinations and so on and you're using a test battery that has no validity why are you doing this this is tantamount to malpractice and yet it's done every day with thousands of people in my country because of psychologists and their collaborators who think that the tests are the only objective way of dealing with this and that rating scales are somehow subjective and tainted and all of the evidence points in the opposite direction so i am on a campaign as i have been for five years now or more to convince my colleagues to stop it that if you want to assess executive functioning in order to say something about this person's life how they're going to function where they're going to be impaired what they're going to be like in the future the rating scale will beat the test four to five times more variance explained by the rating scale so the cheap subjective rating scale will beat your test battery every time that's probably why we're seeing what we see in adhd where only a third of our patients fail the test you just assessed it wrong had you assessed it through a rating scale through parents and teachers you would have seen massive executive impairment and that's not just my opinion if you take adhd symptoms and you correlate them with executive functioning symptoms they are as we say in statistics co-linear they do not form separate dimensions from each other that fact alone tells you that adhd at least as assessed by ratings is efd under another name sct is not and here's the evidence for that this is my executive function rating scale this is based on our national survey of 1800 children from ages five to eighteen and we can break our groups into four groups we have the control group we have those with adhd only in the red sct and the yellow and those who had both disorders isn't that interesting if you forget dsm which says you can't have both of these disorders because they're subtypes of each other and you treat this as comorbidity well guess what you have people that have both disorders so what's the message you should take home from this first message is adhd on every dimension is worse than sct when adhd and sct combine the population is even worse than either disorder alone this graph however would tell you that there's got to be some executive deficits in sct i mean look at that yellow bar compared to that white bar that's the control group but you would be wrong and here's why remember sct correlates to some extent with adhd inattention about 0.4 so that's a contamination what do you get if you remove the overlap you get that that's the amount of variance explained on the rating scale by the different dimensions of these disorders sct explains nothing sct is not related to executive functioning at all any relationship that appears initially is due to comorbidity and overlap to some extent with inattention in adhd inattention in adhd accounts for nearly all of the variants in that rating scale which is why many of us have come to view the inattention dimension as an executive dimension they're one and the same and by the way there are no adhd symptoms in that rating scale so you can't say that we somehow artificially inflated the relationship we made sure there were no adhd symptoms in that rating scale and yet adhd accounts for the vast majority of the evidence this is the adult study so this is ages 18 to 89. now we're beginning to see something interesting the longer you have sct particularly into adulthood it begins to create problems in self-organization it is also linked to some extent but negatively to impulse control so just as we found in children if you have sct you are likely to be very inhibited compared to even typical people and it looks like there's something going on with emotion regulation but i'll explain that shortly because sct has a strong relationship to depression so this just summarizes the graph that i just showed you so i'll skip over that so what have we found we have found that adhd is a massive disorder of executive functioning sct has little if any association with executive functioning and that's just more evidence that these are not proxies not subtypes which means can they overlap if it's comorbidity what's the overlap in the u.s population this is the overlap i'll just summarize it very quickly by saying half of people with one disorder have the other disorder but half don't so they're not proxies they're not subtypes they're separate disorders that can be comorbid the relationship here by the way is identical to that between anxiety and depression and we treat them as distinct which they are but we recognize that many people with one will get the other and that the longer you have one the greater the odds you will develop the other and that i think is what we are seeing here as well so i treat that as evidence of a comorbid relationship not a subtyping relationship what about in school interestingly sct is as bad in school as adhd when it comes to achievement performance grades and the quality of work that you're doing they of course are quite different when it comes to behavior decorum disruptiveness adhd is a highly disruptive disorder sct isn't but when it comes to the performance of the academic work itself this is a very bad disorder to have we've also found that adhd if you study its mistakes is a problem with production people with adhd just don't do a lot of work but what work they do is usually correct the difference eighty-five percent correct in adhd 94 in typical children that's a very minor difference it's one reason why adhd medications don't improve academic achievement there's not much to improve when you only have a nine percent difference the problem with adhd children is they don't do any work in sct children it's not a production problem when we study them in school what we see is errors lots of mistakes it doesn't matter if they finish their work a lot of it's going to be wrong because they're not focusing on what's essential from what's non-essential in the work at least that's our observation of how these children do work we have four studies that show that sct links up with disorders of arithmetic dyscalculia much more than it does disorders of language reading and handwriting uh adhd shows the opposite and there's one study that shows that that's possibly a genetic relationship we need more research on this but there's a tantalizing finding that the learning disabilities that link to sct might be a little different than the learning disabilities we see in adhd both disorders have learning disability as a comorbidity but perhaps a different pattern to those learning disabilities adhd of course contributes to school disruption school discipline being expelled or suspended from school as a form of discipline and sct children show none of that but that is because they're not aggressive they're not impulsive they're not hyperactive they're not disruptive they're just good little kids who stare in the back of the classroom and don't do anything that is what little they do is wrong so sct is a very different picture in a school system than adhd does and for this reason you'll see adhd referred to psychiatrists because of its association with aggression and antisocial behavior and sct gets referred to learning disability specialist special education and developmental and behavioral pediatrics so if you're looking to find these children you're going to find them getting referred through different channels within our community are there family differences yes sct children are pretty good kids to raise if we look at general levels of parenting stress they're very high in adhd children especially because parenting stress is related to oppositional disorder and adhd has 11 times more comorbidity with odd than in the typical population so it's really the defiance the anger the hostility the aggression the refusal that drives parenting stress and adhd is a very distressing disorder in fact if you look across situations in the home you will find that there is almost no situation which adhd children are not very distressing to manage to their parents when you look at sct you get isolated pockets of concern homework school work and sometimes fear relationships and i'll explain that in just a moment but you don't get this massive pervasive distressing level of reports from parents as you get in parents who are trying to raise an adhd child but by the way in case you don't know it research that chris and i have done shows that adhd is as or more difficult in parenting as autism the levels of parenting stress are equivalent if not worse in adhd this is why the peer relationship problems exist the most reliable finding in the literature to date is sct is linked to social withdrawal apprehension perhaps anxiety and basically just lack of interest low initiative not like psychotic or autistic children are they're just shy withdrawn they remind me of jerome kagan's overly inhibited children that he studied in his research at harvard so they're less impaired socially than adhd children would be but they're more impaired than typical children they have fewer friends but they have more friends and adhd children are going to have to put it in ken dodge's terminology adhd children are rejected sct children are neglected they're overlooked as opposed to typical children who are accepted so those are your sort of three taxonomies of social relationships and they differ in those here as well so both contribute to social impairment but they're doing it through unique pathways one through withdrawal apprehension and shyness overly inhibited and the other through aggression disruption impulsivity intrusiveness and aggression what about comorbidity with other disorders well here the two disorders separate massively from each other and again the findings are highly robust there is no relationship of sct to oppositional disorder and by inference nor will there be to conduct disorder antisocial personality psychopathy or drug use because it is that dimension of oppositional disorder that predicts those downstream problems in our longitudinal studies and since sct children not only have no risk of odd their risk is lower than the normal population the relationship between sct and odd is negative not neutral or positive sct protects you from oppositional disorder and by consequence it's also going to protect you from the downstream disorders that go with it the bad news is you have a much higher likelihood of having depression than even adhd children do indeed several studies show that any link between adhd and depression is explained by this dimension if you examine it and you pull it out adhd has no relationship to depression if you don't examine it you will misattribute a comorbidity that perhaps may not be there so that is another reason why researchers need to assess for sct in their results because they will misattribute a finding to another disorder when in fact it's this silent unrecognized disorder that we see both disorders have comorbidities but with sct it's going to be more internalizing disorders depression anxiety withdrawal and with adhd it's going to be more externalizing disorders odd conduct disorder aggression psychopathy delinquency and eventually antisocial personality by adulthood both disorders are linked to autistic spectrum disorders though there's very little research at the moment i don't want to say that it's definitive but a study published just a few months ago out of cincinnati shows that it's sct that is much much more common in autistic spectrum than adhd but because researchers only identify adhd and its inattention they attribute that to autism had they assessed sct separately they wouldn't have done so as often so one of the problems with the comorbidity studies between adhd and autism is a failure to look for another disorder that might be mediating that relationship or explaining that relationship not not mediating it that's not the appropriate term here adhd children have higher rates of comorbidity with all other forms of psychopathology as you see here whereas half of the children with sct had no other disorder and adhd that's very uncommon adhd almost always has comorbid disorders along with it there are two studies of personality traits they also show reliable differences sct is related to fear of punishment uh whereas adhd is related to sensation and reward seeking and that makes sense if sct tracks with internalizing disorders internalizing disorders like anxiety and depression have very high levels of perceived threat from other people in social situations indeed is one of the hallmarks of anxiety disorders is an over-interpretation of threat harm and other adverse consequences adhd doesn't show that sct does so we need some more research on that but we're working on it okay this is our national survey this is my impairment rating scale for children i'll put in a plug for it it's the only normed rating scale of impairment in existence and we have one for adults as well that shocked me you would think that there would be norms for impairment and children and adults on rating scales and there isn't and the ones we have are trivial there's four items on the cbcl how many friends do you have how are you doing in school we assess 15 different domains of children's lives and here's what you see now it's a busy slide it's very noisy i'm not going to spend much time on it what i do want to point out are a couple of findings first of all with few exceptions adhd the yellow bar is more impairing than sct with few exceptions one of those is in sports the other one is with your father except that fell out when we controlled for the sports one why is that your father spends more time engaged in sports with you so the sex difference between parents was being driven by the propensity to play sports with your child otherwise the exclamation marks are where adhd is a much much worse disorder but i want to point out something that most people don't look at unless i mention it look at the blue bar the light blue bar i think it's blue anyway and so sometimes the projectors change colors and i'm also colorblind uh the blue bar shows what it shows that if you have both disorders you are markedly more impaired than either disorder by itself now why is that important to a psychopathologist like me it means that the disorders are additive they're not duplications they're not proxies they're not representations of the other disorder if they were having both disorders wouldn't make you any worse off than having either disorder by itself but repeatedly we have seen additivity when both disorders link up with each other that's just another sign that there's something unique about sct that contributes additional explained variation in impairment these are the adults again ages 18 to 89 in this particular study now we saw something we didn't expect to see sct is worse than adhd in the three areas with the asterisk worse that is shocking adhd is a very impairing disorder in educational and occupational settings by adulthood sct is worse than adhd in those settings look at the third one the third difference i know it's rather humorous but sexual relations with other people are much more adversely affected by sct than adhd and i sort of struggled with that until i spoke to some of my female colleagues as well as my wife who said that if you space out and daydream when you're supposed to be making love to somebody the relationship is over goodbye if your partner has to say earth to steve i'm still here remember me you know the person you happen to be lying with right um that's a sign of disinterest so it's not good uh but the real surprise was in the educational and occupational domains and by the way in case i didn't point it out notice again additivity where you have both disorders you are markedly worse than somebody with either disorder alone so to summarize i'll just do this very quickly because it's very boring adhd is a markedly more impairing disorder across the board than as sct alone when both disorders link up you get additive impairment but there are certain isolated domains of life activities in which sct is actually worse than adhd and that's a double dissociation and that's what we want to see if you want to prove that sct is unique this was done in answer to my chairman his sct daytime sleepiness and joshua langberg did the study and showed that while there is some relationship between ratings of hypersomnia and ratings of sct they cluster differently they factor analyzed differently they share only 25 percent of their variation which means that the variation in one is unique to it and not shared most of the time with the other and therefore it is not hypersomnia by another name so we can throw that out uh as well so it's not depression it's not anxiety it's not hypersomnia it's not adhd it's not autism what the hell is it i don't know but it's not those other disorders and that's important so what causes it we're not sure how many studies of etiology are there less than 10. so we don't know but let's look at some of the glimmering findings here there are now three neuroimaging studies the slide is wrong they all indicate that sct is correlated with posterior activity in the default mode network of the brain which is largely in the parietal area and its overlap with the temporal lobes and more on the left than the right though it is obviously bilateral and it is the network responsible for tada daydreaming begins to suggest that maybe what we're seeing here is pathological daydreaming we'll see now adhd is related to this network as well but in a very circuitous way what do i mean by that adhd shows a bit of a renegade default mode network because the frontal lobe executive system that is supposed to reign it in and control it when there's a goal to be done is very poor so there's little executive management of the mind wandering module in adhd right but that's an executive failure not a default network problem in sct it's the other way around there's no evidence of an executive network problem in sct so we may well have a problem with the dmn the default mode network that is independent of any executive problems in its management there was one study that looked at eeg and evoked potentials and it found that there was a striking difference between the two disorders in sct the problem was very low evoked potentials when the stimulus first hits the brain less than 100 milliseconds so literally as soon as the brain is detecting a stimulus the detection is smaller there's something about the sensory cortex that is not doing well at sensory detection in adhd the problem is in the frontal network that contributes at about 300 plus milliseconds out and that is the persistence activation aspect of an evoked response so there may be some differences here again one or two studies doesn't make a conclusion but some tantalizing suggestions yet again that there's something in the posterior aspects of the brain that are linked to this disorder whereas it's primarily anterior aspects of brain functioning in adhd most recently there is a study that is in press in china the study was reviewed just a couple of weeks ago and it shows that there is a difference in heart rate variability and in responding to sudden changes in the environment basically the difference is this adhd children are show under arousal and if a stimulus occurs if there's a sudden change in the task they don't activate to the uh to the change as well as other people and we've known that going back to keith connor's work in the 1970s there was an under arousability in adhd in sct we show slightly lower resting heart rate but when there is a change there is an over activation in variability which is consistent with anxiety fear concern and worry so the heart rate data actually match the internalizing symptom relationship here but again one study and china at that so we have to replicate this with other labs with other ethnic groups and so on some additional findings these are just like one or two studies each let's look at relationship of sct to other disorders and two of them have been looked at the first is fetal alcohol syndrome sct is much more common in fas and fae exposed babies as they grow up that is adhd indeed the study suggests that as an autism there is an over-attribution of comorbidity to adhd because you didn't assess for sct had you done so you would have pulled those kids out and you wouldn't see a stronger relationship to adhd by the way the same was found in studies of survivors of childhood leukemia the treatments for leukemia produce an attention disorder in survivors uh and uh it looks like it's more sct than even adhd and yet earlier studies only looked at adhd and so reported that there was a increase in adhd inattentive presentation in leukemia survivors and that may not be the case so again we need to explore this more fully i don't want you to walk out if you're assuming that this is all cast in stone and cut and tried and we know what we're talking about these are just tantalizing findings to go further in looking at these populations but it looks like you can acquire an sct-like syndrome from certain injurious brain processes alcohol the neurotoxicity of the all treatments chemotherapy and radiation and others so time will tell we'll see now look at the one study of twins and it's just one though someone has told me that they've replicated this but they haven't published it yet adhd is a highly heritable disorder among the most heritable disorders in psychiatry rivaled only by autism and bipolar disorder in the degree to which human variation is explained by genetic variation in case you're not familiar with it the average heritability is 0.76 in adhd which means 60 76 percent of individual differences in this room in a d each year due to genetic differences in your genome and by the way that figure climbs to 90 or higher if you use clinical levels of adhd diagnostic levels uh but we'll we'll stick with the 0.76 because it it's still substantial and just for comparison purposes students out there the heritability of iq is 0.55 the heritability of personality is 0.4 the heritability of depression is 0.3 to 0.4 and the heritability of anxiety is about 0.3 to 0.4 so to summarize adhd is twice as heritable as personality traits depression and anxiety and is close to the heritability of human height which is 0.91 so as we can say in psychology we have discovered among the most heritable human psychological traits is the traits underlying adhd what did they find in this study with sct it was nearly as heritable but not quite 0.6 roughly 0.55 to 0.6 depending upon how they looked at it so it's up there it's pretty substantial one but not as heritable as adhd which means there's more room for environmental factors contributing to sct than to adhd and now i will go back to the demographics remember the link to social disadvantage parent disability parent unemployment low economic status maybe now we're seeing why sct has an even stronger relationship to those they may have a certain ideological role in an sct presentation than they have an adhd and to support that i just ask you to think about ptsd which of these two attention disorders do you think is most common in ptsd it's sct it's the staring the daydreaming the preoccupation with your thoughts the mind wandering the hyper vigilance then it would be an adhd presentation indeed if adhd occurs with ptsd it's usually a pre-existing condition and it biases you to be more likely to develop ptsd in response including in military veterans but adhd does not arise from that all right so let's let's cut to the chase here let's begin to look at what have we seen now in the nature of sct well it could be a disorder of arousal maybe it's brain stem i don't know i don't think so but uh the relationship to sleepiness doesn't seem to support that uh it could just be another disorder of attention it's a focus problem not an attention problem it could be related to ocd you're a ruminator and you're just repeatedly ruminating of your problems but the one i love is this one it's a form of pathological mind wandering you have an out of control default mode network and you can't regulate your daydreaming your mind wandering it's almost a walter midi syndrome if you want we can't prove that but the neuroimaging studies are supportive this is just a slide on mind wandering i'll skip it this is a beautiful review of all neuroimaging evidence with regard to human mental states was published just a couple of years ago and this is all human mental activity carved up into two dimensions and you can see this is the executive dimension that you see here and this is the one that adhd destroys is goal directed attention and mind wandering is here a somewhat different mental state just above nighttime dreaming but very different than the ruminating ocd type states more in the area of spontaneous thought but unwanted spontaneous thought if you're not familiar with it there's your default mode network it's primarily a posterior hemisphere impairment there's a little bit up here but that's where the executive system operates to shut it down when you're involved in gold erected behavior lastly let's look at treatment not an awful lot of treatment research here but i'll summarize it very quickly adhd medications don't work very well for these children we've known that for a number of years if you have adhd inattentive type you're probably not going to do very well on stimulants and now we have the first study of sct directly at the cincinnati children's hospital that shows that the level of sct is a predictor of poor responding to methylphenidate so the more sct you are the less likely you're going to do well on that medication so that sort of backs up the earlier studies there's a single study of atomoxetine with sct showing that it has selective preferential benefits to treating sct even controlling for its positive benefits on adhd so there's something about a norepinephrine reuptake inhibitor that might prove beneficial to the management of this disorder but again a couple of studies shouldn't be changing our practice to any great extent someone once said maybe we should try ocd type medications like fluvoxamine or that we use for ocd and tourettes uh not sure about that because i don't think this is ocd or ruminative but it could be what about anti-narcoleptics modafinil so on maybe but given that there's an adverse or negative response to methylphenidate meltophenidate is an anti-narcoleptic i'm not sure we're going to find anything there either what about psychosocial treatments we don't know there are three studies one of social skills training showing sct kids probably do a little better in social skills training whereas adhd children do not do well in social skills training and 25 of them get worse social skills training harms adhd children which is why we don't recommend it and that is because of what's called deviancy training aggressive children train up their peers so you don't want to be mixing highly aggressive children in with each other there are side effects to psychosocial treatments and that is one of the adverse events linked to social skills training however social skills training might work well for sct because it's an internalizing type disorder and social skills training has always worked well for anxiety particularly social anxiety more than it ever has for externalizing disorders like adhd we don't know about cognitive therapy it does not work for adhd until adulthood even then it must target executive deficits it works very well for anxiety and depression maybe we should go back and revisit cbt for sct we don't know there's a dissertation for you if you're looking for one i just gave you one linda fifner is the only one who's done behavioral studies of sct and she's found that they do as well or better than adhd children in behavior modification programs that target their symptoms this is just my slide to once again remind you i hate the name of this disorder i wish they would change it my staff and i have come up with this i don't care if you use it or not i would just like to see us move away from what is a demeaning pejorative an offensive label to patients who tell us that repeatedly whenever they they hear that term can't you guys come up with something better and i think we should so to summarize adhd is an executive disorder by another name highly impairing highly associated with disruption dysregulation and so on sct is not adhd is an externalizing disorder it looks like sct is more like an internalizing disorder so if we go down our checklist what's the evidence do we have different symptoms yes do they cohere yes are they distinct dimensions from other forms of psychopathology undoubtedly are there differences in demographics yes the differences in cognitive coral it's probably yes differences impairments probably the more we learn the more yes differences in comorbidity without a doubt that's one of the most reliable differences in the literature what about biological correlates we don't know what about course the first follow-up study was just published a month ago it's a nine-year follow-up of children in spain and it shows that sct is highly stable even more stable than adhd from childhood to adolescents and is a strong predictor of adolescent depression and anxiety even controlling for baseline depression and anxiety in childhood so it looks like it's possibly an internalizing not an externalizing disorder distinct etiology maybe but we don't know what about family history no studies what about treatment response don't have enough evidence to say but at the moment it's looking like treatments for adhd don't work well for sct and we need to go back and explore a new package of treatments for sct thank you [Applause] you're welcome [Applause] 25 years of research in an hour [Laughter] thank you russ you're welcome this is a very thought-provoking presentation and i think a lot of people um you know actually felt yes yes yes on a number of things that you said so time will tell i also think that some people got a bit disappointed at the end because there's so little to suggest but what should we do yes i know we do but we have to live with what we have absolutely right one of the things i was wondering about is the relationship you know we have used much more than most people in the field the concept of developmental coordination disorder oh yes and of course as i was listening to you i can't help but think about a number of cases that we in the past usually have talked with the parents about as this is add rather than you know adhd right and usually that group has more motor control problems than the typical child with adhd and in the past we've always looked at how much does dcd contribute to the poor outcome and they have much more depression yes much more anxiety and so again and even social problems yes yes and even i mean we're definitely going to be hopefully using the cdd yes term rather than distinguished i would like that but you know pick a different term the problem with cdd is it used to mean childhood disintegrative disorder i know and so that might be a problem i know it could be the acronyms are always a problem yeah they're always a problem but they're always also you know stimulating sure right so we're definitely going to be looking more into your model of sluggish cognitive tempo or cdd but i think it would be good if other people were more into also looking at the dcd component and again just as with the rating scales for um these things that they predict much more in terms of real executive function than tests do so does some of the research that we've done on motor control problems in the kids you can have somebody do an extremely thorough motor examination and come up with oh yes there's this and that but not very much but when you actually use it in the form of a questionnaire right you get much more to the root of separation yes yeah yeah and so even though i'm one of the you know strongest opponents of people saying oh we just use rating scales and we don't do anything else we don't even clinically look at the patients i think that's totally wrong yes but i certainly agree with you when it comes to the um risk of using tests for anything other than really iq or achievement or the skills that are associated with the iq test um so that's good to hear because i the the pushback i get from my neuropsychology colleagues who make a living yeah giving test batteries is often rather strong although they cannot provide evidence to support their and also very often the test batteries are so long and takes so much time and if as you say and i think it's quite true that they don't really help you other than the whisk or the vice or whatever predict anything why use them and it just means a lot of services are being used up you know for the diagnosis of something four to six hours since yeah or or days or weeks or months sometimes at least no i agree and it's nice to hear that uh you're seeing the same thing but do you think uh on the basis of your own experience in the field that you shouldn't even try a stimulant in in a case with cdd or sluggish no not necessarily because even the cincinnati studies showed that they don't have an adverse reaction it's not like you've made them worse or done harm what you get is a poor response it's mediocre it's unimpressive the first study that we did showed that 20 of kids with sct responded to methylphenidate they responded at the starting light beginning dose there was no further improvement if you were going to get it you were going to get it there yeah and nowhere else adhd almost never responds at the starting dose and you have to push your dose up to moderate or larger doses to begin to get the effect so what happened at the end of our double-blind placebo-controlled trial in that study 93 of adhd children continued on a stimulant following the trial yeah 20 of sct children were kept on that stimulant so but that's a blinded study of the results do you think it would be a good idea to always at least consider atomoxetine i would use it as the first choice just because we have evidence of a unique effect that's been replicated as well whereas with methylphenidate it's rolling the dice you don't know whether it's going to work or not and i think it's i'd rather use a non-controlled than a controlled substance yeah or would it be a good idea to start with a very small dose of same ethyl phenidate just to see whether it has any effect at all and if it doesn't and you start pushing it up and you see no further positive effect you dry atomoxedin well it's a good suggestion i think to me though the answer to that probably has to do with efficiency and that is that stimulants can be tested immediately they're rapidly acting you're going to know within the first dose whether this is going to benefit this child and let's move on whereas atomoxetine we're talking about one to two weeks of careful titration before we start to see good therapeutic benefits so uh in that sense you'll know right away whether methylphenidate is going to be helpful it still doesn't rule out whether you should go back to atomoxetine or not and i i want to put in a plug again for the the psychosocial treatments anxiety is the best predictor of response to all psychosocial interventions the more anxious you are the better you do whether it's social skills whether it's behavioral uh in school at home whether it's family parent training anxiety is a very good predictor of which children seem to respond well given that these children look like internalizing type children um i think that we shouldn't just be looking at medications i like going back and let's study social skills let's study cbt let's study other interventions no i'm just bringing that up because currently of course there is a worldwide the trend that you were more positive to using medications at all yes in the past in this country it was like no no oh i know but now it's gone the other way i'm old enough and therefore i i just want to hear your opinion about which drug would be more useful to start with and i think you've already responded to that i think it has to do with efficiency yeah but we will hopefully see much more of all types of intervention research for this group which is different from what most people think about us adhd i hope so let me put in a plug to uh students and my junior colleagues if you're looking to make a name for yourself in an area of research and publish don't try adhd it's like going into physics 50 000 studies you have to know you're gonna have to choose a very specific area you could do anything on sct as i was telling your research team this morning it would be instantly publishable it would contribute to the literature you could make a name for yourself you could still study adhd as a control group uh and you would be doing us all a great service uh by publishing in that area as well i think we should end on that note so do i the future is sct or cdd or or whatever yeah something okay all right so much thank you what a pleasure thank you eva thank you as well thank you so much my pleasure [Applause]