cc
I'm a researcher here at the >> Hi, everyone.
in the Department of Waisman Center and a professor
lab is the Learning to Talk lab. Communicative Disorders, and our
and word learning in children I'mwith cochlear implants.und
You're going to hear some of the
some of the other talks. same things that you heard in
with the glass half empty or the Like Ruth I'm going to start
call it good news versus bad glass half full, I'm going to
Cochlear implants are one of the news.
single processing. trials of modern engineering and
have much better speech and Chlanguage skills than we evers
could have imagined looking at
the same type of hearing children a generation ago with
aids. They are mainstreamed, they
speak beautifully, their
We never would have imagined language is excellent.
fast. We also have to acknowledge that
we're not there yet.
as a group, we know there's a Clot of individual variability,
but as a group they don't perform as well as their same
age peers with normal hearing.
intelligible. On every measure of academic
achievement, they don't do quite
Here I'm talking also to know that a lot of our kids with
cochlear implants live, like in Lake Woebegone, all children are
above average.
average score, we're not content We're not content if 100 is the
implants have scores at the that our chiaverage.th cochlear
We want them to be above average
their school or town. Of course here we have to think
of what comparison group we're
We don't want to compare apples gto oranges..
It depends who we compare them
If we compare children with cochlear implants, if we compare
their speech or language, if we compare them to children of the
same chronological age, they're not going to do as well.
It makes sense to compare them
same classrooms, but it's not fair to compare them to these
kids. For one thing, they've been
hearing for less time.
implant at age 1, when you go to Even if you had a cochlear
been hearing for four years, kindergarten at age 5, you've
hearing for five years. We could instead compare them to
children of the same hearing
We could take kids and say, okay, you're five, but you've
only been hearing for four
you do compared to kids of 4 years, so we're going to see how
When we do that, they often do years.
That makes sense. Even if you get your cochlear
implant at age 1, you don't start learning everything at age
1.
speak and learn words, but Maybe you start learning to
things from when you were born you've been learning lots of
The difference between the to age 1.
even if you don't know the words concepts of an apple and orange,
What we often do in our lab is apple and orange.
the same size vocabulary. cAnd when we compare them toh
children who have the same
similarities between children vocwith cochlear implants andost
children with normal hearing. The problem is that children
with cochlear implants tend to
delayed in vocabulary. be on the average of six months
Now, you know, as people have already said, it's obvious why
we have these differences.
isn't as good. You know, the auditory input
So they don't have as good 22 channels versus thousands.
haven't been hearing for as auditory inplong.nd they also
As people have been saying, we
these areas that are going on have even as we speak.es in
So what we're doing in our -- you know, we're not engineers,
we're not surgeons in my lab. So what we're doing is focusing
on two things.
speech and language development is different for children with
cochlear implants as we compare them to children with normal
hearing.
producing sounds and perceiving This is sounds. terms of
Also in terms of learning words.
individual differences in And we'rperformance.ested in
So if you remember back to
was a huge range of performance Rutin children with cochlearhere
implants. Some children are really what we
call stars. They perform as well or better
than children with normal hearing.
And what we'd like to do is think of -- try to understand as
well as we can what is going on with this -- with this
variability, so that we can potentially make all children
into stars, all children
with normal hearing. performing as well as children
the things we found, I want to So before I talk about a few of
talks about the interactions show you this diagram which
producing speech, and learning between perceiving speech,
So let's start here with speech perception.
This is going to be things like being able to hear the
difference between a ka and a ta, or a and ay, and this is
where we expect children with cochlear implants to have
problems. The auditory implant isn't as
good. And hearing the difference
between ka and ta is really hard.
The problem here is that this interacts with everything else.
So speech perception interacts
Being able to make the with speech production.
or an ah and ay. difference between a ka and ta
production is, the better your The better your speech
the better your speech speech perception will be, and
speech production will be. perception is, the better your
the more, the better you get at Wperception and production, the
better memories you're going to have with these individual
speech sounds.
you know, having memories for words, you really have two kinds
of memories.
Obviously we know the difference You have word meanings.
bird in and something you eat on between something you keep a
memory for a word, we don't just a birthday, but when we have a
we also have the memory of its have the memory of its meaning,
We also know that cake is different than cage because one
ends in k, and one ends in ja.
speech sounds, the better you'll The better memories you have no
words. do at learning and remembering
even farther up. We could have this diagram go
reading and writing, things Up important for academicike
achievement.
think that's most important for being a good reader are knowing
lots of words, and being able to
sounds. You see this one weak link in
speech perception can lead to problems, difficulties all the
way up. This is what we're interested
in. I can show you a couple results
that we have that show
between children with cochlear similarities and differences
normal hearing. So this is from work that a
graduate student did, and what
children produce sounds. she was interested in was how
sa and cha, like sip and chip, and she
recorded them from children with
with normal hearing of the cochlear implants, and children
She was measuring the acoustics in the sounds, and one of
the big differences has to do with the frequencies between
the sounds of sa and cha. Sa has a higher frequency
than cha. You see the results here for
children with cochlear implants and children with normal
hearing.
along the vertical axis. This measure of frequency is
in the white bars, Sa frequency results are shown
are shown in the gray bars. There were all productions that
listeners heard, and said that
You can see for both groups, sounds like a good sound.
sa than for cha, but you can see there's a higher frequency for
more distinguished in the children with normal hearing
than the children with cochlear implants.
There's a more robust contrast. There's a bigger contrast
between the two sounds in the children with normal hearing.
Maybe it's things like this,
differences that lead to the maybe it's these subtle
implants being just a little speech of children with cochlear
The other thing that is interesting here, the -- these
black lines are the average, but
every individual child in these we've alsocircles. data for
You see, first of all, there's
groups. These are 2 and 3-year-olds.
You can also see there's at least one child with a cochlear
implant who is performing just
with normal hearing. as well as the best children
stars. That shows you there are these
be. ThatIn this next slide we'ree to
comparing children with cochlear
the same size vocabulary. And this experiment had to do
with learning novel words.
actually a word, but it might be If I said a word you to, this is
pulchritude. an novel word to you,
is encode it enough that you The first thing you'd have to do
Whether you know this word or not, you would be good as
repeating it. It's like attitude, latitude.
It's not hard to remember and say pulchritude.
This is something we've known no
vocabulary the better you can repeat a new word, and that is
something that is very important
We did a similar experiment, not for word learning.
up words, and we got exactly with pulchritude, but with made
We got the receptive vocabulary, that result.
along this axis, how accurate hthey were in repeating noveld
words along this axis.
vocabulary increases, they're You see fmore accurate. as their
What is really cool about this
children with cochlear implants slide, we in black.he data for
The data for children with
see the exact same relationship. normal hearing in red, and you
size they're just as good as Once they get that vocabulary
That's a very exciting result. repeating novel words.
is that when we match children The a little bit of concern here
with cochlear implants were on for vocabulary size to children
younger. the average about six months
size they're functioning, Wthey're learning new words atry
least to the point of repeating them in just the same way that
children with normal hearing
So that's exciting. This result is for adults.
And this is from work of Matt Wynn, who is in the audience.
His picture is here so you can
He's a post-doc, who's working find him later.
This is work he did with other with Ruth and me.
Maryland when he was a graduate colleagues astudent.iversity of
He was interested in the same sounds, sa and cha, in
perception of those sounds, and telling them apart both in
adults with normal hearing and
He gave them two conditions. adults with cochlear implants.
and female voices, and he gave The listeners heard both male
He gave them one condition where them two conditions.
female voice, and a male face with a male voice, and in the
other condition they just heard the voices, and didn't see the
faces.
cochlear implants were more sensitive to the visual cues.
They paid more attention to the faces than the adults with
normal hearing. In a way this makes sense.
If the auditory signal isn't as good you should be trying to use
other cues that you might not have to have if you have normal
hearing.
were paying attention to a cue So what they were doing, they
hearing listener redundant, or that might be in a normal
listener with cochlear implants because the auditory input is
degraded. So with these results, I say the
million dollars question is how can these results inform
clinical progress.
answers yet, but one thing I I wouldn't say we have a lot of
particularly looking at Matt's think we have to do,
do auditory verbal therapy. rIn auditory verbal therapy thee
focus is I'm getting the child
they're hearing to the extent that we don't even provide them
with facial cues. There certainly are advantages
to that in that we really want
auditory input that they haven't kids to concentrate on the
implant is activated. haBut it could be that we'rer
carrying it a bit too far in not
integrate visual cues. also teaching children to
one condition for children in Mauditory verbal therapy wheren
sometimes they're getting the auditory cues only, and
sometimes getting the auditory
Because we know, we suspect that and the visual cues.
implant user, you're going to have to use all the cues that
you have at your disposal,
degraded. I want to switch gears a little
bit now and talk about another
our children be stars. approach that might help all of
something that is a little And here I want to talk about
word learning, and that is further away from speech and
Executive function is what executive function.
processes involved in the psregulation of three things.ive
One of these things is working
Working memory is a little memory.
Working memory has both stored
space and processing space. And working memory capacity is
limited, as I'm sure we've all
The example I like to give is how you can drive and talk at
the same time until the driving gets bad.
All of a sudden you're in a lot of traffic or it starts pouring
down rain, and you say to the person sitting next you to, I
can't talk anymore, I have to concentrate on driving.
Cognitive flexibility is being
another. able to switch from one task to
know that is something that Any ofdevelops gradually.hildren
That's why we give our children warning about transitions.
Five more minutes, and it's going to be time to get ready
for bed.
what it sounds like. Inhibitory control is exactly
impulses. Instead of grabbing the last
cookie on the plate, look around
saying, does anyone else want at everyothat cookie?he table
We know all these things
and working memory, develop ingradually from childhood toty,
adulthood.
this is that executive function Wseems to be involved in speech
perception and in word learning.
adults who have better executive So in our lab we've seen that
this by standardized tasks, pay more attention to redundant cues
and speech perception.
of sa versus cha, the primary cue in English, the difference
between cha and sa
There's other cues. iThey're not as important in.
English, but they're there. Another important cue is the
frequency at the beginning of the vowel.
What we find is that people who have poor executive function as
measured by tasks tend to pay attention only to that primary
cue, whereas people with better executive function pay attention
to both the primary cue and the secondary cues.
Other people, David Pisoni
that children and adults who at Indiana University has shown
measured by standardized tasks have better executive function
are better able to recognize or sometimes by questionnaires
If you ask someone to listen to a passage, and press a button
every time they hear the word cup, people with better
executive function who have cochlear implants will be faster
and more accurate at that task. So this suggests that possibly
teaching -- you know, having
better executive function might presult in better outcomes with
cochlear implants in terms of children and possibly adults.
Now what is exciting about that,
original talk that Teresa ifPalumbo gave, the Center forhe
Improving Health and Minds, which is right here at the
Waisman Center has developed a
executive function. It's similar, I don't know if
anyone hear has done as an adult
The program is very similar to a mindfulness stress reduction.
reduction program, except it's mindfulness based stress
preschoolers. It starts with children lying on
their back, and they watch
stomach as they're taking belly breaths then they're asked
to hold up a finger when they hear a bell stop ringing,
and so on.
about, I don't know, half an It's a six week program for
to be effective in improving hour a day, and it's been shown
preschoolers and early school executage kids.ion in
It'd be really exciting to do such a program with children
with cochlear implants, and see if that does translate into
better speech perception or word
So I'd like to thank my wonderful collaborators for
their generous support we've had
and I can take questions. [applause]