What is narcolepsy?
Narcolepsy is a major sleep disorder that involves a defect in a neurochemical
pathway in the brain. The result of that is that people are excessively sleepy,
and they have disorders of REM sleep in particular.
And this is how you would describe a good portion of teenagers?
Well, in a sample that we looked at, we could describe half of them like
That sounds risky to me. Is that risky to you as a researcher?
That was the finding that got my attention and really made me think that, you
know, these early school start times -- and this was in a sample of kids who
were going to school, I think, first bell was 7:20 in the morning. They just
weren't adapting to it. They weren't accommodating to it, and it was producing
this awful effect.
Is it dangerous? I think it is, particularly with so many teenagers driving
themselves to school in the morning. They'll do anything to get a few more
minutes of sleep in the morning, so they don't take the bus if they possibly
can't. As soon as they get a car, they're in it, and they use it to get to
school and to get that extra 10, 15, 20 minutes of sleep in the morning. So
here are these sleepy teens on the road when they're maximally impaired.
So it's risky for driving. Are there other risks to it?
We think there are other risks, and we don't have all the data to know. But
it's clear that one of the big risks seems to be the effect on mood and the
ability for teenagers to regulate mood. We see across the country a new wave --
if not epidemic -- of depression in teenagers. We don't know yet one for one,
but there's this sneaking suspicion out there that one of the things that leads
into depression is this hyper-somnolence and this sort of change in overall
mood and affect that some of these teenagers undergo. And I think if you're
vulnerable to that pathway to depression, that is a serious risk of this huge
amount of sleep debt in teenagers.
Why is this happening at this particular time?
That's an interesting question: Why is it happening now? There seems to have
been a change that's happened kind of gradually over time in how schools are
regulating their starting times. When you combine that with kind of the social
zeitgeist now with all of the things that teenagers have available to them that
occur late at night, from televisions and telephones and computers in the
bedrooms to jobs that they take that go late into the night, their sleep has
been shoved into an ever-narrowing window. So it's partly societal, cultural,
and it's partly this sort of demand of the adult world. Then we have to fit in
the kids' biology into that system that we're left with. The puzzle isn't all
working out. ...
What we are finding also is a lot of kids just [don't go to] school. So all of
a sudden, the day will come when they just can't marshal their resources, as
slim as they are in the morning, to get up for school. They just say they're
not going to school today. More and more, we're seeing kids not [missing]
school because they're sick; it's just they're too tired. ...
Is the teens' biology different from younger children and adults?
What we know about teenagers is they still need as much sleep as they did when
they were pre-teens. So the need for sleep, in spite of our sort of common
notions that the older you are the less sleep you need, that doesn't seem to be
true across that span from, say, age 8, 9, 10 to age 20, and we don't know
quite beyond that. So that's point number one.
And then within that time frame, it appears as if there are changes in the way
the brain is regulating sleep and the timing of sleep. So one of the things
that our research is examining is this delay, or later bed times, later wake-up
times that occur in teenagers, and to what extent the brain is producing that
kind of delay. So that's the biology we think is changing during adolescent
What can be done about [this problem of teens not getting enough
This is a bigger problem than just adolescence. Our society in general has sort
of put sleep in the back seat, doesn't think about sleep anymore, and doesn't
really understand or acknowledge the importance of sleep. So for me, sort of
the battle is to have a more generally acknowledged positive priority on sleep.
I think we need to be teaching about sleep.
It's so interesting to me that you can go into classrooms with tiny little kids
and you can learn the food pyramid and you can learn the importance of not
smoking and of wearing helmets and so forth, and not ever hear word one about
sleep. Furthermore, you can see that all the way through school, into college,
into medical school... The amount of information that's being taught in formal
curricula about sleep is virtually nil. So I think that's going to have a big
I think that adolescents in particular need to know about sleep. Their parents,
teachers, school administrators, the school nurses need to know. And maybe we
need to start reexamining the issue of the school starting time, and really
turn back the clock a little bit to give these kids a break.
When school districts have bumped up their start time, what has been the
result of that?
The few school districts that have made starting time later for teenagers, some
of them are reporting very positive response, both from the teachers, parents,
the kids. It's just they talk about it as being a tangibly happier environment.
There is a group in Minneapolis that's tracking some schools in that area of
the country who've made the change, and they're finding mixed results.
It's interesting. My interpretation of some of their most recent results [is
that] they're not really seeing big bursts of higher grades in school. They're
seeing more kids in the classroom. So fewer of these kids are not being able to
get up and make it to school. That means you have a bigger sample altogether,
and I think that's affecting some of their results on grades.
But there have been some other districts where it's just sort of blown up in
the face of the schools when they've tried to delay. If the schools don't do
some education in advance of making this change, it can negative outcomes. ...
Parents have structures, daycare and childcare for the little ones being
provided by the older ones. It just can get out of control unless there's some
groundwork laid, some preparation. And again, we come back to this issue of
In your writing, you talk about a "forbidden zone" of sleep. What do you
mean by that?
It's interesting. When we talk about how sleep is controlled by the brain, we
really are talking about two systems. One is the system that fills the tank at
night, and the other is the biological clock system. It sets up a sort of cycle
of when it's easy to fall asleep and when it's hard to fall asleep. Those times
when it's hard to fall asleep we call "forbidden zones" for sleep.
We see in many adolescents that this forbidden zone is in the evening hours. So
they actually feel great at night and, for many of them, that makes it harder
for them to even consider trying to go to bed earlier. So they'll say goodnight
to Mom and Dad and they'll go into their rooms and read or play video games or
talk on the phone. And they're perfectly content and happy doing that, because
they're also at a phase where it's easy for them to become aroused and
stimulated by these activities. So it really does turn into a Catch--22. When
people just say, "Well, all they have to do is go to bed earlier," well, they
really can't go to sleep earlier necessarily.
What can be done on an individual basis?
Kids who are struggling with this need to assess what's going on in their lives
and what changes and what is important and how to do it. You can't just all of
a sudden turn back the clock and make a big change overnight. The brain and the
body and the timing systems don't work that way. So gradual changes can be
Our brain learns when it's night and when it should be sleeping by the
information it gets through our eyes, and that's light. It seems as if
teenagers limit the amount of light they get at nighttime and maximize the
amount of light they get in the morning hours. That helps to turn the clock
back a little bit earlier for them and enables them to go to sleep earlier.
Some teenagers might benefit from an after-school nap; that actually can help a
lot. But it doesn't help this morning empty tank. A nap in the afternoon
doesn't fill the morning's tank.
What about this teenage pattern of going to sleep quite late, getting up
early in the morning for the week, and then sleeping very late on the weekends?
Are they catching up?
We get "binge sleeping," as we call it. It actually does help to catch up, and
it helps to replenish the stores of sleep. But it has a negative impact,
because it's giving the brain a different message about when nighttime is. So
kids who sleep, say, 11 p.m. to 6 a.m. on school days, and then on weekends
stay up until 2 a.m. or 3 a.m. and sleep until 2 p.m. or 3 p.m., they're
replenishing their sleep stores.
But now they're telling the brain, "Well, nighttime is really 2 a.m. to 2 p.m."
That's just a terrible message for the brain to start having on Monday morning,
when it's trying to get back on the school schedule. So again, we're sort of in
this very tough situation of what you do under those circumstances.
What I think would help is if teenagers could do whatever they can on school
nights to get eight-and-a-half hours in bed, sleeping. They're still going to
get a sleep debt, but it's not going to be this massive sleep debt. And then on
weekend nights, if they sleep in and get nine, ten, ten-and-a-half hours, it's
not giving the clock this huge wrong messages, and it is enough to replenish
the sleep storage depot. ...
We saw an experiment where you put on lights at certain times of the night
that the light would not normally come on. Can you explain to us what you were
doing with that?
We're trying to find out if one of the things that may be changing in the
brains of adolescents is when the clock in their brain is sensitive to light.
What we think may be happening, and we have a little bit of evidence now, is
that the little kids, before they reach puberty, are very sensitive to light in
the morning. And that's why they can fall asleep easily at night and they wake
up in the morning with joy in their hearts and songs on their lips.
The older kids, we think, may be less sensitive to light in the morning and
more sensitive to light in the evening. And that may be what's pushing their
clocks to a later timing system, because evening light is a signal for the
clock that, "Oh, it's not night yet, so we better move later." So when we're
doing those tests. That's the question that we're trying to answer.
And you answer it by testing melatonin levels?
Right. ... Melatonin is the brain's hormone of darkness, so the brain turns on
melatonin production when it's the nighttime of the brain. You can shut that
off by shining a light through the eyes. And the question is, how much light
does it take to shut down melatonin? That gives us some sense of how the
brain's clock is reacting to light. ...
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