ruth litovsky university of wisconsin madison, wi usa
DESCRIPTION
Ruth Litovsky University of Wisconsin Madison, WI USA. Brain Plasticity and Development in Children and Adults with Cochlear Implants. [email protected] http:/ /www.waisman.wisc.edu. Waisman DWE June 23 2013. How are CI users doing?. - PowerPoint PPT PresentationTRANSCRIPT
Ruth LitovskyUniversity of
WisconsinMadison, WI USA
Brain Plasticity and Development in Children and Adults with
Cochlear Implants
[email protected]://www.waisman.wisc.eduWaisman DWE June 23 2013
How are CI users doing?
The CI converts acoustic input into electrical stimulation of the auditory nerve to provide: Speech/Language Music Sound localization Quality of life Etc…
How are CI users doing?World-wide ~ 250,000 recipients Speech/Language Music Sound localization Quality of life Etc…
How are CI users doing? Is the glass “half full” or “half
empty” ?The field has come a long
way….Many CI users have excellent speech production and receptive language skills.But, other CI users struggle to
attain speech and language, especially without “speech reading” (auditory only)
Language comprehension Language expression
Niparko et al. (2010)
Our recent research shows that:1) Language perception: most children are within 1 SD of mean2) Language production: >50% children +/- 1SD; some are below
Language comprehension Language expression
Who are the children we study? Bilateral cochlear implants High maternal education SES is generally high Children have high IQ and memory testing
scores Not typical of CI population, but likely provide
information on “best possible outcomes”
Bilateral Cochlear Implants Bilateral CIs provided to
growing number of patients. Goal: Improve hearing in noise,
sound localization, quality of life.
Age of bilateral activation in many clinics is 12 months or younger.
But are we providing them with the best possible input that will maximize outcomes?
-50 º
-40 º
-30 º-20 º
-10 º 10 º20 º
30 º
40 º
50 º
0 º
Studies in adults: Sound localization in Noise
Sound localization error is lower using 2 CIs compared with 1
Bilateral CIUnilateral CI
Jones et al. (Litovsky lab)
Unilateral: 77.7°
Norm
al: 6.7°
Mean RMS Localization Errors
Bilateral: 25.3°
Localization with CIs is much poorer than normal hearing listeners
Bilateral CI
Normal hearing
Unilateral CI
Unilateral: 77.7°
Norm
al: 6.7°
Mean RMS Localization Errors
Jones et al. (under preparation)
Sound Localization in 5-12 yr. olds
NH-Study1NH-Study2
BiCI (BI)BiCI (Uni)
RM
S e
rror
(deg
rees
)
0
10
20
30
40
50
60
Litovsky and Godar (2010)
Grieco-Calub and Litovsky (2010)
Bilateral
Unilateral
RMS error: Sound Localization in 5-12 yr. olds
Normal Hearing BiCI
Review; Litovsky (2011)
GAP NH vs. CI
Testing “toddlers”: (2-3 years old)Left/Right Discrimination
Orienting to sound
Grieco-Calub, Litovsky, Werner (2008)Grieco-Calub & Litovsky (2012)
Right – Left Discrimination (MAA)
Grieco-Calub, Litovsky, Werner (2008)Grieco-Calub & Litovsky (2012)
Normal Hearing
BilateralCIs
< 12 months
> 12 months
Experience withBilateral CIs
10 unableTo perform the task
10 With Uni CIs Unable to performthe task
?????
Toddlers: Reaching for sound(Ecologically / motivating task)
StimulusWhen I hide I say…
Litovsky et al. (2012, in press)
Results All toddlers tested with the “Reaching for
sound” test were able to discriminate Left vs. Right.
However, their ability to localize was poorer than normal-hearing toddlers.
? Do they simply not have a well developed map of space?
? Are the processors not providing them with ideal cues for localizing?
Some factors affecting performance
Behind-the-ear (BTE) location of microphones
Signal processing compromises acoustic cues
Location of electrode within the cochlea
Difference in the insertion of electrodes between ears
Neural pathway degradation
Brain “Plasticity” In order for cochlear implants to be able to work, the
brain has to adapt to new information, to convert electrical signals to meaningful everyday sounds (speech, music, etc.).
Plasticity is the brain’s ability to change, re-organize, respond to new information.
Experience, plasticity……
Deaf Unilateral Bilateral
Chronological age at CI1Length of Bilateral
Experience
Hearing age
Birth(deaf)
1st CI 2nd CI
Later-onset deafnessSpatial map emerges
or re-emerges
“Plasticity” Depends on history,
etiology. Depends where in the
brain we look. More plasticity at “higher”
centers. More hard-wired at lower centers (training may be critical).
Important to get the peripheral information to be as good as it can be.
Other sources of limitations: Today’s CIs are Bilateral
Because…. The CIs in the two ears function independently. No guarantee that stimuli will activate devices such that ITDs or ILDs are preserved with fidelity
Goal: to provide Binaural hearing
Next Step: Reverse Engineering Using Research Processors
Using a Personal Digital Assistant (PDA) to load binaural software and interface with a binaural “card” for hardware (in collaboration with UT Dallas).
Research processors provided by CI manufacturers to control inputs to the two ears “at the bench”
Final note: Bottom-up & Top-down What about other sources of
variability?CognitiveExecutive functionMemory Incidental learningHow does brain plasticity
interact with these?
Misurelli and Litovsky, in prep.
Conclusions1. We are looking to close the gap between
bilateral CI users and NH binaural listeners. 2. Optimizing localization in bilaterally
implanted children may require experience with binaural cues.
3. Cognition and top-down processes may play an important role.
Thanks to the Binaural Lab
Work funded by NIH-NIDCD R01-DC003083 & R01-DC008365
Waisman Center
Univ. of WisconsinMadison
Exp. 1: Discriminating Right vs. Left Child only sees 2 holes in curtain:
+/- 60+/-45+/-30+/-15
Test at each pair to determine if child can: discriminate Left vs. Right bilaterally vs. unilaterally
Litovsky et al. (2012, in press)
Even though they can discriminate L-R, BiCI toddlers find it harder than NH toddlers
NH BiCI
# Tr
ials
to R
each
Crit
erio
n
0
20
40
60
80
100
Children1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
# Tr
ials
to R
each
Crit
erio
n
0
20
40
60
80(A)
(B)
BiCINormal Hearing
*
Children1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Pro
porti
on V
alid
Tria
ls
0
20
40
60
80
100
NH BiCI
Pro
porti
on V
alid
Tria
ls
0
20
40
60
80
100
(A)
(B)
BiCINormal Hearing
*
Litovsky et al. (2013)
Exp. 2: Localizing (9 alternative forced choice)Children with Normal Hearing
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
atio
n (
)
Pc = 88.46%
RMS = 5.1
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 88.46%RMS = 5.1= 3 responses
= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 100%
RMS = 0
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 100%RMS = 0
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 14.81%
RMS = 35.59
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 14.81%RMS = 35.59
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation
( )
Pc = 96.3%
RMS = 2.89
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 96.3%RMS = 2.89= 4 responses
= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation
( )
Pc = 83.33%
RMS = 8.66
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 83.33%
RMS = 8.66
= 4 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation
( )
Pc = 96.3%
RMS = 2.89
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 96.3%
RMS = 2.89= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 74.07%
RMS = 10.41
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 74.07%
RMS = 10.41
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Res
pons
e Lo
catio
n (
)
Pc = 92.59%
RMS = 4.08
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 92.59%RMS = 4.08
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 66.67%
RMS = 10
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 66.67%RMS = 10
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 92.59%
RMS = 14.43
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 92.59%RMS = 14.43
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 33.33%
RMS = 33.17
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 33.33%RMS = 33.17
= 2 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 83.33%
RMS = 13.69
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 83.33%
RMS = 13.69= 6 responses= 1 response
COO COR COS COT
COV COW COX CPF
CPH CPK
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 88.46%
RMS = 5.1
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 88.46%RMS = 5.1= 3 responses
= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
atio
n (
)
Pc = 100%
RMS = 0
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 100%
RMS = 0
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 14.81%
RMS = 35.59
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 14.81%RMS = 35.59
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation
( )
Pc = 96.3%
RMS = 2.89
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 96.3%
RMS = 2.89= 4 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 83.33%
RMS = 8.66
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 83.33%
RMS = 8.66
= 4 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 96.3%
RMS = 2.89
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 96.3%
RMS = 2.89= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation (
)
Pc = 74.07%
RMS = 10.41
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 74.07%
RMS = 10.41
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Res
pons
e Lo
catio
n (
)
Pc = 92.59%
RMS = 4.08
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 92.59%RMS = 4.08
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
ation
( )
Pc = 66.67%
RMS = 10
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 66.67%RMS = 10
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 92.59%
RMS = 14.43
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 92.59%RMS = 14.43
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 33.33%
RMS = 33.17
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 33.33%
RMS = 33.17
= 2 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
ation
( )
Pc = 83.33%
RMS = 13.69
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 83.33%
RMS = 13.69= 6 responses= 1 response
CPH CPK
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Res
pons
e Lo
catio
n ( )
Pc = 21.82%
RMS = 52.39
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 21.82%RMS = 52.39
= 4 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n ( )
Pc = 37.04%
RMS = 40.52
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n (
)
Pc = 37.04%RMS = 40.52
= 2 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Res
pons
e Lo
catio
n ( )
Pc = 11.11%
RMS = 42.62
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 11.11%RMS = 42.62
= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Res
pons
e Lo
catio
n (
)
Pc = 38.1%
RMS = 42.17
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 38.1%RMS = 42.17
= 4 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Res
pons
e Lo
catio
n (
)
Pc = 19.44%
RMS = 37.17
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 19.44%
RMS = 37.17= 3 responses= 1 response
-60 -45 -30 -15 0 15 30 45 60
-60
-45
-30
-15
0
15
30
45
60
Target Location ()
Resp
onse
Loc
atio
n (
)
Pc = 15.56%
RMS = 43.13
-60 -45 -30 -15 0 15 30 45 60-60
-45
-30
-15
0
15
30
45
60
Target Location ( )
Resp
onse
Loc
atio
n (
)
Pc = 15.56%RMS = 43.13= 3 responses
= 1 response
CIEP CIEQ CIER
CIEY CIEZ CIBF
Exp. 2: Localizing (9 alternative forced choice)Children with Normal Hearing