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- So we define autism as
a behavioral syndrome,

which means it's a co-occurrence

of certain behavioral phenomena.

There are two key phenomenon.

One are certain kinds
of social deficits.

Deficits in regards
to social interaction.

And the other domain
is a little bit of

a messier umbrella term.

We use the term ritualistic
repetitive behaviors.

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Autism is defined
by behaviors only.

So it's very different
from diabetes

that we have a very specific

biological test
about insulin levels,

or a sickle cell that we
know is due to a single gene.

And as a result, it's a bit
of a hodgepodge, frankly.

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It's defined clinically on
the basis of these behaviors

because currently
that's what we treat.

But what we've learned over
the last 10 or 15 years

particularly from genetics

is that there are
multiple autisms.

We have some people with autism

that have intellectual
disability.

What used to be termed
mental retardation.

We have some that
have high IQ's.

We have some that have
more severe ritualistic

and repetitive
behaviors, and some

that have milder ritualistic
and repetitive behaviors.

As we sort of look
under the hood,

when we look at the brain
or we look at genetics,

based on defining
people as having autism,

we find a bunch of
different stuff,

and that's essentially
a problem in our field

because we find too much.