Autism spectrum disorder is pretty common.
The World Health Organization estimates
that at least 1 in 100 people today have that diagnosis.
And some say it could be twice as many.
But while all autistic people are united under the same label,
it is a diverse group.
You could be a middle-aged white woman
who communicates through an iPad and pointing,
and who lives in a group home with round the clock care.
You could be an older African-American man
who’s married and works at a museum
where you get to wow people
with all of your knowledge on your favorite topic.
You could be a young Vietnamese girl
who walks on your tiptoes and plays the same game
by yourself during play time every day.
If you’re not autistic,
you might still see yourself in some of those descriptions.
And if you are, you might not identify with any of them.
That’s because autism isn’t one thing.
It’s a spectrum.
It affects a variety of people in a variety of ways.
But we haven’t always understood it that way.
Over the years,
researchers and the Diagnostic and Statistical Manual,
or DSM,
have updated who falls under that umbrella
and what kinds of diagnoses
and therapies might come with it.
So here’s what we know today about the entire spectrum of autism …
where it comes from, how to recognize it, and what comes after diagnosis.
(intro song) First of all,
autism hasn’t always been thought of as a spectrum.
The scientists and clinicians
who wrote the first reports back in the day
were not taking into consideration a lot of the people
who would be diagnosed as autistic today.
Which is why in the 1940s,
they described it as a quote; “rare disorder.”
It was a diagnosis given to people
who were especially sensitive to certain stimuli;
avoided hugs, eye-contact, and other social contact;
felt particularly drawn to routines;
repeated certain words and movements;
tended to get totally absorbed by an object;
and either didn’t use language at all
or didn’t appear to use language to communicate with other people.
And many autistic people today
can relate to at least some of the stuff on that list.
But there’s a lot to unpack
between those early descriptions and now.
In 1994, the fourth edition of the DSM came out and drew some new distinctions.
For people who weren’t intellectually disabled and aligned
with fewer of the communication criteria,
there was a new diagnosis, separate from autism:
Asperger’s disorder.
This new diagnosis
was already a bit controversial
because the children that Dr. Hans Asperger
wrote papers about in the 1940s
wouldn’t have qualified as having Asperger’s disorder
the way it was described in the DSM-4.
Not to mention the controversial circumstances
under which Asperger published his findings.
He began his scientific career in Nazi Germany,
so there’s a lot of debate
around the underlying goals of creating those diagnoses.
But Asperger’s wasn’t the only addition to the DSM-4.
A few other diagnoses with overlapping symptoms
also came onto the scene,
broadly referred to as pervasive developmental disorders.
And when it comes down to it,
whether you were diagnosed with Asperger’s
or a pervasive developmental disorder,
you probably had overlapping symptoms
with people diagnosed with autism.
So the next time the DSM was updated, in 2013,
all of those diagnoses were smooshed
into autism spectrum disorder.
And we continue to call it the autism spectrum today.
But everyone seems to have their own definition for what “spectrum” means.
Some researchers refer to it as a scale of functionality or severity,
based on things like the extent to which you depend on others
to complete daily activities.
And there’s a huge range of support
that people across the autism spectrum might receive.
But others, including some people in the autism community,
prefer to view the spectrum more neutrally, like the color spectrum.
In that framing, different people have different qualities,
but one shade of autism isn’t better or worse than another.
So while the debate continues
about what exactly the “spectrum” means,
the current accepted diagnosis is autism spectrum disorder.
And there are biological reasons to support thinking about it that way.
Even after a century of research,
we’re still in the very early days of understanding
where the symptoms of autism spectrum disorder come from.
But genes do seem to play a role.
One publication from 2019 surveyed the genes
of more than a thousand autistic people and their relatives.
And they found rare genetic underpinnings for autism
that have also been linked to stuff
that’s sometimes associated with autism,
like schizophrenia and ADHD.
It often comes down to things like deletions
and duplications of parts of your genetic code.
And that’s the kind of thing that can be inherited …
or not.
Now, I know that’s not a specific answer to the genetic question.
But that’s because, as far as we know,
autism isn’t like sickle cell disease
where you always get that diagnosis
if you inherit a particular gene.
It’s a more varied diagnosis with more varied sources.
In the 2019 study, most of the participants
had no clinically relevant genetic changes.
But about 10% of them had at least one, and they were not all the same one.
In total, this study found 209 genetic changes
that are likely to be involved in creating the autistic experience …
but only for those 10% of autistic people. .
If you’re one of those 10%,
you might want to know what causes your genes
to change like that.
It is not vaccines.
As usual, the dark corners of the internet
are wrong about this claim.
It has been refuted by many peer-reviewed studies
that strongly conclude there is no link between vaccines and autism.
But there are some epigenetic changes
that researchers have linked to the condition.
That’s the term for when your lived experience changes
the way your body uses your genes.
A particular environment or experience
can alter your DNA through a process called methylation.
One carbon and threea hydrogen atoms,
which chemists call a methyl group
get added onto part of your existing genetic code.
And this change can keep that genetic code from being read,
as if it’s been turned off.
Another study published in 2019
found differently methylated DNA
in the brains of autistic people who had donated their bodies
to science upon their deaths.
The investigators compared brain tissue
from people who had and had not been diagnosed
with autism spectrum disorder back when they were alive.
And they found 111 genetic sites that were differently methylated
between the two groups!
Of them, about 18% seem to actually matter.
Like, you can put a stop sign in the middle of a corn field
and it won’t change traffic patterns.
But if you put that stop sign on a busy street,
it’ll have more of an effect.
So 18% of these methyl stop signs were put in places
where they metaphorically stopped traffic for those genes.
One of those places is thought to be a kind of Autism Avenue,
where a lot of methyl groups were found to stop traffic
on a gene that has already been associated
with the autism spectrum.
Have we taken this metaphor far enough??
Probably. I’ll give it a rest.
Despite the vast spectrum of autism,
these researchers found
that different manifestations of the diagnosis
have the same DNA methylation patterns.
So across the spectrum,
certain genes associated with autism
may be altered and contribute to the experience.
These genes regulate all sorts of stuff like immune function,
sending information from one part of your brain to another,
and forming new neural connections.
So it’s no wonder that there are many layers
to the autism spectrum.
And if we go even farther down the rabbit hole,
some researchers have come up with ideas
for what inspires these methyl groups
to attach to autistic people’s DNA
more than other people’s in the first place.
One popular theory
is that the age of your father
when you’re born matters.
Some research suggests
that you’re more likely to be autistic
if you had an older male parent because sperm mutates
more with age.
In this context, “older” refers to people over 40 years old.
But that’s not to say that everyone over 40 will have autistic children
or that all autistic babies were born to people over 40.
There are just studies that suggest
it’s more common at the population level.
Another potential source of epigenetic changes associated
with the autism spectrum is the immune system.
Several reports from Europe and North America
say that people who developed in the womb of someone
with an autoimmune disease are
more likely to be diagnosed with autism,
with some specific diseases
increasing the likelihood by up to 80 percent.
But it ranges a lot depending on the autoimmune disease
and its onset timing.
For example, thyroid disease is particularly relevant,
while psoriasis and rheumatoid arthritis
are not significantly associated with the autism spectrum.
Scientists think that pregnant people with autoimmune diseases
make more antibodies than those without.
And they’ve found that people
who gave birth to autistic babies
made specific antibodies
that other pregnant people didn’t make.
Those antibodies target proteins in the baby’s brain,
which could make it inflamed and change the way it develops.
And, yes, brain development
is yet another potential source of autism.
But I’ll get into that later in the video.
The point is: there are a lot of possible origin stories for autism
and none of them apply to everyone on the spectrum.
And you better believe that scientists are still looking into it.
In the last few years,
the National Institutes of Health started pushing for autism research
and funded a veritable butt-load of projects along those lines.
But because of the whole spectrum of it all,
many avenues of research could be related to the disorder.
It’s very possible that a diagnosis this complex
is the result of several interconnected causes.
So we still don’t know exactly what gives you autistic traits.
But a lot more progress has been made in the area of diagnosis.
Today, we know the autism spectrum
doesn’t discriminate the way people once thought it did.
I mean,
the Centers for Disease Control and Prevention in the US
still report that white children are more likely
to be diagnosed with autism spectrum disorder
than other groups.
But it’s more complicated than that.
Some statistics might fool you
into thinking that autism is a white person’s diagnosis.
But that’s more reflective of other factors
than lower prevalence in some groups.
In fact, one study from 2014
found a higher rate of autism
in Black, Asian, and most Hispanic populations,
when the data was adjusted for things like socioeconomic status.
So it’s not just white boys.
But it’s also not just boys.
All sexes are represented in the autism spectrum.
Even Asperger himself had female patients.
And that was back in the early days
of quantifying and defining autism.
Today, we also know that the spectrum
includes people who are nonverbal
and people who are incredibly talkative.
An autism spectrum diagnosis means
you might communicate differently
than people who don’t have that diagnosis.
And individuals across the spectrum run the communication gamut.
A research article published in 2020 tested this concept
using a modified version of the telephone game.
That like, party game
where one person
tells something to the next person
and they have to relay the same message to the next person,
and on and on.
Finally, the last person in the line speaks up
and tells the room that
“Atlantis spies on you from space”
when the original message was
“I’d like to pie you in the face.”
So it’s a test of how well we can relay information.
And in this study, groups of autistic people,
non-autistic people,
and mixed groups were asked to play the same game.
The results demonstrated that a group of autistic people communicates information
just as effectively as a group of non-autistic people.
But communication breaks down earlier in the mixed groups.
Now, if you go on for long enough,
all three have equally bad information retention.
That’s kind of how the telephone game works.
The important part
is that autistic people have similar skill levels in communication
compared to non-autistic people,
and there’s a mutual lack of understanding
when we’re trying to communicate
with people outside of our group.
This is a huge finding that flies
in the face of years of clinicians and researchers
claiming that autistic people have a communication deficit.
According to this study,
it’s a communication difference.
But, of course,
that perspective is representative
of only a specific sliver of the spectrum.
The participants in this study were verbal,
with an average IQ,
no anxiety disorders,
and diagnosed with autism spectrum disorder as adults.
If you’re mostly nonverbal,
your game of telephone
would be different and might yield different results.
In fact, your entire life may look different
from the lives of the people the 2020 study
recruited to play the telephone game.
The autism spectrum includes people who can live independently
and people who rely more on others for their daily activities.
And in each of these facets of identity,
from sex to communication to independence,
there are autistic people everywhere in between the extremes.
Like, you might have met someone on the spectrum
who’s really skilled at calculations or music.
Maybe you mentioned your birthday
and they were able to tell you immediately
what day of the week that was.
This is what people are referring to when they talk about “superpowers.”
But the term that academics use is “savant syndrome.”
About half of all recorded savants
are on the spectrum,
which is why they’re often associated with each other.
But only one tenth of the people diagnosed with autism are savants.
So this definitely isn’t a trait that comes as a package deal
with all of the other lived experiences of the spectrum.
Being on the spectrum doesn’t inherently mean you are a savant.
And you can be a savant without being on the spectrum.
Also, there isn’t a set IQ range that savants stay within.
Some savants have a high IQ and some have a lower one.
Importantly,
the IQ test only measures specific facets of intelligence.
If you’re a savant,
you’re incredibly intelligent in ways that others fall short,
regardless of that one assessment.
For example,
the researcher who first described savants
talked about someone who could recite
the entire six volumes of
“The Decline And Fall of the Roman Empire”
forwards or backwards from memory.
So that’s a quality that some people on the spectrum have,
it’s also a quality that you can have
even if you’re not autistic.
And many savants who aren’t on the spectrum
still share experiences with some people who are.
Like not speaking as a young child,
which also happens in Einstein’s syndrome,
or reading at an early age,
which is also known as hyperlexia.
This overlap can create confusion.
If you aren’t autistic but have these other conditions,
you could easily get diagnosed as being on the spectrum.
Then, you might get interventions that aren’t super effective for you.
And you’d develop in ways that are typical for what you actually have.
Children with Einstein’s syndrome,
for example, can start out nonverbal
and then develop speech later on.
That kind of significant communication change with age
isn’t characteristic of autism spectrum disorder.
Being autistic is a lifelong thing.
It won’t go away with age.
But for some autistic individuals,
certain symptoms become less pronounced as you get older.
I say “some” because it depends on the circumstance.
People who are intellectually disabled and nonverbal
tend to have more pronounced symptoms
that don’t change as much over time.
In a large study with more than 240 people on the spectrum,
half of the verbal participants had some symptom improvement.
But even among the people
who showed reduced symptoms over time,
they didn’t grow out of autism.
They continued to meet the standards
for diagnosis and had low social reciprocity.
The back and forths of your conversation
don’t quite look the same
even if you’re no longer hyper focused on one topic.
For those who show change over time,
it might be related to your aging brain,
specifically a group of brain cells called mirror neurons.
These are cells that activate
when you do something
and see someone else doing the same thing.
A study published in 2011
found that children and adolescents on the spectrum
don’t activate a part of their brain called the inferior frontal gyrus much.
And that’s where these mirror neurons are.
But some autistic adults activate
their inferior frontal gyrus and mirror neurons more,
to the point where they’re statistically
the same as adults who aren’t on the spectrum.
So that might explain
why some autistic people have improved communication skills with age.
Now, the brain scans in this study
can’t tell us whether that brain change
directly leads to the social change.
There’s just a correlation.
But the bottom line is that autism,
like a diamond, is forever.
And it’s usually noticeable starting around age two.
So let’s say you’ve noticed autistic traits in yourself or your child.
Here’s how you’d confirm
that you’re on the spectrum
rather than experiencing some other condition.
First, you’d go through a screening.
This is the first assessment that usually happens
through your primary care physician
during a regular check-up.
Depending on how old you are,
there are different versions of the preliminary screen.
Guardians of children 18-24 months old
usually fill out the Modified Checklist for Autism in Toddlers,
or the M-CHAT.
This is the most commonly used questionnaire
in Europe and the US.
One question asks if a child follows a pointing finger
to the object the finger is directed toward.
Another asks if they get upset by everyday noises.
Another question asks if the child is interested in other children.
The questions range from gauging interest to response to activity.
And if the answers to at least three of the 20 questions
align with a spectrum diagnosis,
then the child may be autistic.
Adolescents can be assessed utilizing similar instruments,
such as the Gilliam Autism Rating Scale or GARS.
Again, this kind of assessment
is filled out by caregivers or teachers,
and looks for things like repetitive behaviors or emotional responses.
An autism diagnosis for adults
tends to begin with a self-report assessment
such as the Autism Spectrum Quotient .
These forms ask people to rate their agreement with statements
such as "I find it difficult to work out people's intentions"
and "I prefer to do things the same way over and over again."
The big difference here is that
it's not a parent or caregiver filling out this assessment,
but the autistic person themselves.
Although sometimes,
a clinician will help them interpret the questions.
And if you’re nonverbal,
you might take the Universal Test of Nonverbal Intelligence,
which is administered and answered nonverbally.
It tests things like spatial memory, reasoning,
and the ability to complete mazes.
Depending on how you score, these assessments
can help connect you with resources
like in-home support, group homes,
and training for jobs.
Once you’re diagnosed with autism spectrum disorder,
you can start interventions that can change your life for the better.
If you’re nonverbal,
you may be able to learn to use a keyboard,
iPad graphics system, gestures,
or sign language to communicate.
If you have low muscle tone,
a common symptom,
you can get physical therapy
to build up your strength, coordination, and balance.
And many people on the spectrum
receive some kind of behavioral therapy.
The whole idea is to figure out the function
of a harmful behavior,
like banging your head against a wall,
and replace it with something
that more safely achieves that function,
such as pressing your head into a pillow to get some sensory input.
Historically, the first step, where you remove a behavior,
was done through measures
that many people consider unacceptable now,
like using shocks, or spray bottles,
or even immobilization.
Today, you’re more likely to have a distraction removed
or be told that you didn’t perform the desired task correctly.
But the treatment still faces a lot of criticism.
Some people who have undergone applied behavior analysis
found it extremely unpleasant
or felt as though they were having their identity stripped away.
And it’s not a small commitment, either.
The guy who came up with applied behavioral analysis
found that people
who followed the protocol for 40 hours per week
had the best results.
That’s a full US work week’s worth of training.
But a 2018 study found
that children who received just 10 hours of training per week
for 28 weeks
sometimes showed larger behavioral change
than those who did more sessions.
So maybe the full time job of training one kid
isn’t always necessary.
But it might also depend on when you start.
The 2018 study found
that the younger children were when they started interventions,
the more improvement they showed.
As in, younger than 28 months old!
So there really is something to the idea
that earlier intervention is more effective.
Ultimately,
there are a variety of tools for the variety of symptoms
that come with autism spectrum disorder.
But I can’t stand here and tell you
that they’re all perfect.
Behavioral therapy can encourage new coping mechanisms
as alternatives to self-harm or property destruction.
But that kind of intervention
doesn’t make stimuli go away or become less overwhelming.
Which is one reason that research is still ongoing.
For all of its flaws,
applied behavioral analysis is regarded
as the only effective evidence-based intervention
for someone on the spectrum.
And in reality, none of these options will cure autism.
This has become a supercharged topic
as many people have developed
an appreciation for neurodivergence
and have come to think of autism
less as a disease and more as a difference.
But there are drugs that can help manage symptoms like trouble sleeping or focusing.
Ultimately, for many people,
the diagnosis is less about finding therapies
and more about providing an explanation for your experience of the world.
At the end of the day,
it can be a great way to find community.
It may be decades before we understand
all aspects of the autism spectrum.
But if the coming decades
show as much progress as the last ones have,
we’ll know a lot more about it than we do today.
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we could not do what we do
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