Takayuki Nakata- nakata@n-
junshin.ac.jp
Department of Psychology
Nagasaki Junshin Catholic University
235 Mitsuyama-machi
Nagasaki-shi, Nagasaki-ken, 852-8558, JAPAN
Sandra E. Trehub
Department of Psychology
University of Toronto at Mississauga
Yukihiko Kanda
Nagasaki Bell Hearing Center
Haruo Takahashi
Division of Otorhinolaryngology
Department of Translational Medical Science
Nagasaki University Graduate School of Biomedical Sciences
Popular version of paper 3aPP3
Presented Thursday morning, November 30, 2006
4th ASA/ASJ Joint Meeting, Honolulu, HI
Cochlear
implants are becoming the prostheses of choice for many deaf children and
adults. They enable deaf adults to perceive speech effectively in favorable (quiet)
environments, and they enable many congenitally deaf children to acquire
the speech and language of their community. Because the devices provide relatively
coarse pitch information, they not ideal for music. Thus, child implant
users, like adults, have difficulty recognizing familiar music from pitch
cues alone. Unlike adults, however, child implant users enjoy musical
activities, and many of them sing.
The present study is the first to examine the
singing of congenitally deaf children who use cochlear implants (CIs). Our principal goal
was to determine the extent to which young implant users preserve the relative
pitch and timing of the original songs. The participants were
12 congenitally deaf Japanese children who were five to 10 years of age and six normally hearing
Japanese children who were five to nine years of age. All children sang songs from memory, and
recordings of those songs were analyzed instrumentally to reveal their pitch
and timing characteristics.
Comparisons of the timing or relative note durations
in deaf and normal-hearing children's songs revealed considerable similarities. By contrast,
the pitch patterning of deaf children's songs was substantially different from
that of normal-hearing children. For example, the pitch range of deaf children's songs
was greatly compressed, about one third of the range used by normal-hearing impaired children.
Moreover, the pitch contours of deaf children's songs were unrelated to those
of the target song. For example, in reproducing a rising pitch, deaf children
were as likely to produce a falling as a rising pitch.
In short, deaf children reproduced the temporal patterning, or rhythm,
of familiar songs, but not the pitch patterning or melody. These findings
confirm deaf children's interest in songs and their long-term memory for
certain features of songs. Without frequent singing of the target songs at home
or elsewhere, child implant users would have been unable to remember the
details that they reproduced (e.g., words and rhythms). Moreover, their singing
exuded the energy and vitality that are characteristic of non-audibly impaired children's singing.
It seems that congenitally deaf implant users' experience of music is very
different from that of implant users who lost their hearing as adults.
In
short, the present findings indicate that congenitally deaf children who use cochlear
implants can sing familiar songs from memory. They successfully capture
the rhythmic patterns of songs as well as normally hearing children do. However,
their pitch patterning is grossly distorted. For congenitally deaf children
with cochlear implants, the power and pleasure of music likely stem from its
rhythm. From a Western perspective, this may seem unusual, but rhythm is
central to musical expression in many parts of the world (e.g., Indian
classical music, African drumming). In fact, rhythm plays a critical role in
music perception from the early months of life. As the present study indicates,
timing is central to the musical experience of congenitally deaf implant users
for whom melody is largely imperceptible.
Sound files:
Child A with cochlear implant singing original melody
Child B with cochlear implant singing original melody