Toward a new understanding of mental illness Thomas Insel

[Music]

so let’s start with some good news and

the good news has to do with what do we

know based on biomedical research that

actually has changed the outcomes for

many very serious diseases start with

leukemia acute lymphoblastic leukemia a

ll most common cancer of children when I

was a student the mortality rate was

about 95 percent today some 2530 years

later we’re talking about a mortality

rate that’s reduced by 85 percent 6000

children each year who would have

previously died of this disease are

cured if you want the really big numbers

look at these numbers for heart disease

heart disease used to be the biggest

killer particularly for men in their 40s

today we’ve seen a 63 percent reduction

in mortality from heart disease

remarkably 1.1 million deaths averted

every year aids incredibly big has just

been named in the past month a chronic

disease meaning that a 20 year old it

becomes infected with HIV as expected

not to live weeks months are a couple of

years as we said only a decade ago that

is thought to live decades probably to

die in his 60s or 70s from other causes

altogether these are just remarkable

remarkable changes in the outlook for

some of the biggest killers and one in

particular that you probably wouldn’t

know about stroke which has been along

with heart disease one of the biggest

killers in this country is a disease in

which now we know that if you can get

people into the emergency room within

three hours of the onset some 30% of

them will be able to leave the hospital

without any disability whatsoever

remarkable stories good news stories all

of which boiled down to understanding

something about the diseases that has

allowed us to detect early and intervene

early early detection early intervention

that’s the story for these successes

unfortunately the news is not all good

let’s talk about one other story which

has to do with suicide now this is of

course not a disease per se it’s a

condition or it’s a situation that leads

to mortality what you may not realize is

just how prevalent it is there are

thirty eight thousand suicides each year

in the United States that means one

about every 15 minutes third most common

cause of death amongst people between

the ages of 15 and 25 it’s kind of an

extraordinary story when you realize

that this is twice as common as homicide

and actually more common as a source of

death than traffic fatalities in this

country now when we talk about suicide

there is also a medical contribution

here because ninety percent of suicides

are related to a mental illness

depression bipolar disorder

schizophrenia anorexia borderline

personality there’s a long list of

disorders that contribute and as I

mentioned before often early in life but

it’s not just the mortality from these

disorders it’s also morbidity if you

look at disability as measured by the

World Health Organization with something

they call the disability adjusted life

years it’s kind of a metric that nobody

would think of except in economists

except it’s one way of trying to capture

what is lost in terms of disability from

medical causes and as you can see

virtually 30% of all disability from all

medical causes can be attributed to

mental disorders neuropsychiatric

syndromes you’re probably thinking that

doesn’t make any sense I mean cancer

seems far more serious heart disease

seems far more serious but you can see

actually they’re further down this list

and that’s because we’re talking here

about disability what drives the

disability for these disorders like

schizophrenia and bipolar and depression

why are they number one here well there

are probably three reasons one is that

they’re highly prevalent about one in

five people will suffer from one of

these disorders in the course of their

lifetime the second of course is that

for some people these become truly

disabling and it’s about four to five

percent perhaps one in twenty

but what really drives the

numbers this high morbidity and to some

extent the high mortality is the fact

that these start very early in life

50% will have onset by age 14 75% by age

a picture that is very different than

what one would see if you’re talking

about cancer or heart disease diabetes

hypertension most of the major illnesses

that we think about as being sources of

morbidity and mortality these are indeed

the chronic disorders of young people

now I started by telling you that there

were some good news stories this is

obviously not one of them this is the

part of it that is perhaps most

difficult and in a sense this is a kind

of confession for me my job is to

actually make sure that we make progress

on all of these disorders I work for the

federal government actually I work for

you you pay my salary and and maybe at

this point when you know what I do or

maybe what I failed to do you’ll think

that I probably ought to be fired and I

could certainly understand that but what

I want to suggest and the reason I’m

here is to tell you that I think we’re

about to be in a very different world as

we think about these these illnesses

what I’ve been talking to you about so

far is mental disorders diseases of the

mind that’s actually becoming a rather

unpopular term these days and people

feel that for whatever reason it’s

politically better to use the term

behavioral disorders and to talk about

these as disorders of behavior fair

enough they are disorders of behavior

and they are disorders of the mind but

what I want to suggest to you is that

both of those terms which have been in

play for a century or more are actually

now impediments to progress that what we

need conceptually to make progress here

is to rethink these disorders as brain

disorders now for some of you you’re

gonna say oh my goodness here we go

again we’re gonna hear about a

biochemical imbalance so we’re going to

hear about drugs or we’re going to hear

about some very simplistic notion that

will take our subjective experience and

turn it into MA

molecules or maybe into some sort of

very flat unit dimensional understanding

of what it is to have depression or

schizophrenia when we talk about the

brain it is anything but uni-dimensional

or simplistic or reductionistic it

depends of course of what scale or what

scope you want to think about but this

is an organ of surreal complexity and we

are just beginning to understand how to

even study it whether you’re thinking

about the hundred billion neurons that

are in the cortex or the hundred

trillion synapses they make up all the

connections we have just begun to try to

figure out how do we take this very

complex machine that does extraordinary

kinds of information processing and and

use our own minds to understand this

very complex brain that supports it

supports our own minds it’s a it’s

actually a kind of cruel trick of

evolution that we simply don’t have a

brain that seems to be wired well enough

to understand itself in a sense it

actually makes you feel that when you’re

in the safe zone of studying behavior or

cognition something you can observe that

in a way feels more simplistic and

reductionistic than trying to engage

this very complex mysterious organ that

we’re beginning to try to understand now

already in the case of the brain

disorders that I’ve been talking to you

about depression obsessive compulsive

disorder post-traumatic stress disorder

well we don’t have a an in-depth

understanding of how they are abnormally

processed or what the brain is doing in

these illnesses we have been able to

already identify some of the

connectional differences or some of the

ways in which the circuitry is different

for people who have these disorders we

call this the human connectome and you

can think about the connectome sort of

as the wiring diagram of the brain

you’ll hear more about this in a few

minutes the important piece here is that

as you begin to look at people who have

these disorders the one in five of us

who struggle in some way you find that

there’s a lot of very

in the way that the brain is wired but

there are some predictable patterns and

those patterns are risk factors for

developing one of these disorders it’s a

little different than the way we think

about brain disorders like Huntington’s

or Parkinson’s or Alzheimer’s disease

where you have a bombed-out part of your

cortex if you were talking about traffic

jams or sometimes detours or sometimes

problems with just the way that things

are connected and the way that the brain

functions you could if you want compare

this to on the one hand a myocardial

infarction a heart attack where you have

dead tissue in the heart versus neighbor

is Mia where that organ simply isn’t

functioning because of the communication

problems within it either one would kill

you and only one of them will you find a

major lesion as we think about this

maybe it’s better to actually go a

little deeper into one particular

disorder and that would be schizophrenia

yes I think that’s a good case for

helping to understand why thinking of

this as a brain disorder matters these

are scans from Judy Rapoport and her

colleagues at the National Institute of

Mental Health in which they studied

children with very early onset

schizophrenia and you can see already in

the top there’s areas that are red or

orange yellow are places where there’s

less gray matter and as they followed

them over five years comparing them to

age match controls you can see that

particularly in areas like the dorsal

lateral prefrontal cortex or the

superior temporal gyrus there’s a

profound loss of gray matter it’s

important if you try to model this you

can think about normal development as a

loss of cortical mass loss of cortical

gray matter and what’s happening in

schizophrenia is that you overshoot that

mark and at some point when you

overshoot you cross a threshold and it’s

that threshold where we talk we say this

is a person who has this disease because

they have the behavioral symptoms of

hallucinations and delusions that’s

something we can observe but look at

this closely and you can see that

actually they’ve crossed a different

threshold that crossed a brain threshold

much earlier that perhaps not at age 22

or 20 but even by age 15 or 16 you can

begin to see that trajectory for

development is quite different at the

level of the brain not at the level of

behavior why does this matter well first

because for brain disorders behavior is

the last

thing to change we know that for

Alzheimer’s for Parkinson’s for

Huntington’s there are changes in the

brain a decade or more

before you see the first signs of a

behavioral change the tools that we have

now allow us to detect these brain

changes much earlier long before the

symptoms emerge but most important go

back to where we started the good news

stories in medicine are early detection

early intervention if we waited until

the heart attack we would be sacrificing

1.1 million lives every year in this

country to heart disease that is

precisely what we do today when we

decide that everybody with one of these

brain disorders brain circuit disorders

has a behavioral disorder we wait until

the behavior becomes manifest

that’s not early detection that’s not

early intervention now to be clear we’re

not quite ready to do this we don’t have

all the facts we don’t actually even

know what the tools will be nor what to

precisely look for in every case to be

able to get there before the behavior

emerges as different but this tells us

how we need to think about it and where

we need to go are we going to be there

soon I think that this is something that

will happen over the course of the next

few years but I’d like to finish with a

quote about trying to predict how this

will happen by somebody who’s thought a

lot about changes in concepts and

changes in technology we always

overestimate the change that will occur

in the next two years and underestimate

the change that will occur in the next

10 Bill Gates thanks very much

[Applause]