A Comparison of Esophageal and Electrolarynx
Speech Using Audio and Audiovisual Recordings
An Honors Thesis (ID 499)
Mary L. Salzmann
Dr. William Kramer
-,
Ball State University
Muncie, Indiana
May 1987
Spring Quarter 1987
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TABLE OF CONTENTS
Page
I.
II.
III.
Introduction •
1
Review of Related Literature •
2
Esophageal speech •
2
Electrolarynx speech
3
Research
5
Quality of alaryngeal speech
9
Method •
• 12
Subjects
• 12
Instrumentation •
• 12
Procedures
. 12
Statistical design and analysis of data • • 13
IV.
Results
Charts
V.
VI.
· 14
· 16
Discussion •
· 17
References
• 18
INTRODUCTION
There
are several a1aryngea1 speech methods
available
speech,
to
the
puncture,
the
laryngectomized
e1ectro1arynx,
for example.
popu1ation--esophagea1
and
the
tracheoesophageal
These methods are used with
varying
To the
average
degrees of satisfaction
college-age student
presently
by the
who has
patients.
previous contact
with
1aryngectomees, however, the speech methods may be met
with
a wide range of reactions
had no
and preferences.
The purpose
of
this study is to survey the listener satisfaction of a group
of college-age students who have had no previous contact
with a1aryngea1
speech
ratings of esophageal
to determine
speech as
speech.
Comparisons will
obtained
from
compared to
also be
audiovisual
their
reactions
electro larynx
made between
presentation
and
and
the
data
audio
from
presentation only.
Several
comparing the
methods.
studies have been
performed to collect
acceptability of
specific a1aryngea1
speech
Of these, many of the subjects chosen to rate
a1aryngea1
speaker
Clinicians in
were
the field
speech-language
of speech-language
speech method
which will
study will concentrate
of
college
influence
on the
pathology
students
who
have
never
This
ratings of
a
encountered
esophageal speech or e1ectro1arynx speech, neither
or aurally.
may
a1aryngea1
their ratings.
reactions and
the
pathologists.
already have strong preferences for a particular
group
data
visually
REVIEW OF THE LITERATURE
The removal of a larynx leaves the patient without
form of speech
of a team
communication, necessitating the
of professionals to
The
condition.
primary
pathologist is to
help him adjust
goal
of
work with the
the
any
assistance
to his
new
speech-language
laryngectomee to help
him
develop functional speech by the use of an alaryngeal speech
method.
The term
"alaryngeal speech", first introduced
Kallen and later
popularized by
Diederich and
Youngstrom,
refers to any type of phonation used without a larynx,
as
esophageal
voice,
buccal
speech,
electronic larynges (Boone, 1977).
-
use of the electronic larynx
and
by
the
such
use
of
Esophageal voice and the
are the two alaryngeal
speech
methods focused on in this study.
Esophageal speech is produced
esophagus and producing sound
vibration of
Three
the upper
methods
of
inhalation, and
produces the best
inhalation.
air
by taking air into
the
by releasing air through
the
esophageal tract
intake
swallowing.
sound is a
may
The
be
method
(Aronson,
used--injection,
with
typically
combination of injection
-
4.
and
Effective esophageal speech is characterized by
the following:
1.
2.
3.
1980) .
Reliable phonation on demand.
Rapid air intake.
Short latency between air intake and
phonation.
Four to nine syllables per air charge.
5.
-.
Two to three seconds duration per air intake.
85-129 words per minute.
Fundamental frequency of 52-82 Hz •
An average intensity of 6-7 dB below normal.
Good intelligibility.
6.
7.
8.
9.
.
(Aronson, 1980).
Not all laryngectomees are
capable of developing
effective
esophageal speech due to physical or psychological
According to Salmon (1979)
1/3
of
the
esophageal
population
communication.
using
literature claims
(Schaefer
evidence supports that at
laryngectomized
laryngectomees
and
There
rates
fail
are
functional
success
Johns,
factors.
a
achieve
number
esophageal
98%
the
literature ranges from a "low of 30% poor results to a
high
57.4%
failure
rate."
(Schaefer
Traditionally, rehabilitation efforts
acquisition of esophageal speech.
been a change in attitude
cites
and
that
of
Duguay
of
speech;
25%
of between
1982) .
to
least
and
1982) .
Johns,
have centered on
More recently,
and the use of the
there
the
has
electrolarynx
has been employed as an aid in esophageal speech acquisition
programs.
Today the electronic
artificial larynx is
frequently
used to provide effective immediate voice production.
prosthesis is more
due to
the increasing
communication needs
such
-
widely accepted
as
esophageal
electrolarynx
was
emphasis
rather than
speech
developed
by speech
on meeting
pathologists
the
a particular
(Weiss,
by
1985).
the
This
Bell
patients'
speech
The
mode
first
Telephone
Laboratories in 1959
Electric Company.
and was marketed
The most
developed in 1985, is the
There are several
through the
recent version
Western
unit,
of this
1986).
Model C (Blom and Salmon,
brands of electronic
1.)
larynges:
The
Western Electric Electronic Larynx Model 5C is a
neck-type,
battery powered and sells
The
Neovox Electronic
Larynx by
neck-type,
battery
$250-300.
3.)
by Siemens
neck-type,
and 5.)
2.)
Aurex Corporation,
rechargeable),
is a
and
neck-type,
for $400-500.
Larynx
is
sells
sold
by
4.)
Park
battery
The Barts
Surgical
for
Swift, 1984).
The
powered
Vibrator
is
Luminaud
battery powered
most widely
a
$200-250.,
The Cooper-Rand Electronic Larynx sold by
for $150-200 is a tube-in-mouth type,
a
sold
Company
battery powered model which sells for
(Prater and
Aurex
Siemens Servox Electronic Larynx,
The
model which sells
the
powered
Corporation,
Electronic
for about $100.
model
used type
of
electrolarynx is a hand-held model which is placed firmly on
the neck on the
area which is the
patient.
model
The
has
transmits the vibrations
a
best for the
vibrating
individual
diaphragm
through the skin
which
of the neck
and
into the hypopharynx (Prater and Swift, 1984).
The selection
used depends
1984):
1.)
loss, 2.)
on the
of the alaryngeal
following factors
physical factors
the noise level
of motivation
be
(Prater and
Swift,
such as the degree of
tissue
of the environment in which
laryngectomized patient will
patients' level
speech method to
have to
communicate, 3.)
for learning
an
the
the
alaryngeal
-
speech method,
and
4.)
the
personal preference
of
the
patient.
According to Boone (1977), it is frequently stated
that "if
the new
before learning
laryngectomee uses
esophageal speech,
esophageal speech."
This
an artificial
he will
has been
larynx
never
disputed
develop
by
several
authors (Boone, 1977; Prater and Swift, 1984; and Salmon and
Goldstein, 1978); and, as Duguay states, "I have never heard
of any case or seen
use of
an
a published report indicating that
artificial
esophageal speech"
larynx negated
(Salmon and
the
the
acquisition
Goldstein, 1978).
It
of
has
been proven that the use of the electrolarynx has been
beneficial in the training of esophageal speech.
There
are several
esophageal speech
advantages and
and electrolarynx
advantage of providing immediate
an esophageal
training
laryngectomees
incapable
esophageal speech,
provides a higher
and 5.)
a
following
1.)
2.)
provides
time
upset
to
(Prater and
to
according to
and
produces an inhuman sound quality,
used as a crutch,
requires the
(1978),
method
are
4. )
speech,
esophageal
Swift,
disadvantages of artificial
Goldstein
in
other
learn,
Some of the possible
Salmon
the
functional
than esophageal
temporary alternative
of
immediate
producing
takes less
fatigued or
are
provides speech
of
intensity level
provides
speech when
-.
3. )
Besides
effective speech while
larynges:
speech after laryngeal surgery,
for
speech.
program, the
benefits of artificial
disadvantages
1984).
larynges,
that
it
is a sign of defeat,
is
use of a hand, is
expensive
is
to maintain,
bulky,
calls attention
to
lack
the
of
ability to speak normally, and makes casual remarks
awkward
to produce.
As
in artificial
advantages
disadvantages
and
me tho d .
larynx speech,
are
There
various
excessive swallowing of air,
training time,
esophageal
speech
unnecessary stoma
noise,
distracting noise, and
facial
not as effective
requires
in noisy
more
environments,
and involves latency between air intake and phonation
causes pauses
speech
are
electronic
in
speech.
closely
The
related
laryngeal
advantages
to
the
speech--it
does
instrument or the use of
of
behaviors
Esophageal speech
1977).
is
several
undesirable
these include
esophageal speech;
grimaces (Boone,
the
to
there are
either hand,
of
which
esophageal
disadvantages
not
of
require
sounds more
an
natural,
and does not cost anything.
Many studies have investigated the preferences
esophageal
and
electronic
contradictory results.
in 1955,
laryngeal
speech
between
revealing
In an early study conducted by Hyman
college students
judged audiotape
recordings
esophageal speakers, artificial larynx speakers, and
speakers.
normal
The data revealed that artificial larynx speakers
were preferred in comparison to esophageal speakers
and Goldstein,
Shames, Font,
--..
of
1978).
and
In later
Matthews, 1963;
studies
Bennett
(Salmon
(Crouse,
and
1962;
Weinberg,
1973; and Kalb, 1977), esophageal speakers were preferred in
comparison to
Goldstein, 1978).
varied.
In
laryngeal
artificial
conditions
The
the Crouse study
used and the
speakers
two groups of
of the
(Salmon
latter
studies
audiovisual presentation
speakers were rated
a group
was
by both
group of trained speech pathologists and a group of
speech pathologists and
and
a
trained
of nonprofessionals;
both
groups preferred esophageal speech over artificial laryngeal
speech.
Esophageal
speakers
were
rated
superior
to
artificial laryngeal speakers on one word intelligibility in
the
Shames,
Font,
significant
and
difference
intelligibility.
and
study, which used
speech,
a group
no
sentence
the
Goldstein
of
artificial
of naive
results
(1978),
esophageal
and the
a
proficient
In
this
reading of
preference
speech.
in 1977
and
laryngeal
listeners.
showed
esophageal over artificial laryngeal
intelligibility
in
employing
audiotape samples
passage,
Salmon and
however,
noted
of esophageal,
normal
laryngectomees and
standard
was
study;
In 1973, Bennett and Weinberg compared the
acceptability ratings
speech,
Matthews
Kalb
of
According
compared
artificial
a
to
the
laryngeal
speech produced by different speakers as well as by the same
speaker,
producing
interesting
results.
Using
30
naive
listeners to determine word intelligibility, Kalb discovered
that there was no significant difference between
esophageal
speech and artificial laryngeal speech when each method
produced by the same speaker;
however, when the two
methods were used by different speakers,
was
speech
esophageal speakers
were
rated
more
intelligible
than
artificial
speakers (Salmon and Goldstein, 1978).
study may
have been
influenced by
laryngeal
The results of
the various
this
levels
of
proficiency of the individual speakers.
A study performed in 1963 by McCroskey and Mulligan may
indicate perceptual differences between trained professional
listeners and naive listeners.
more
intelligible
professional
than
and
Esophageal speech was
artificial
student
laryngeal
listeners;
in
rated
speech
by
naive
contrast,
listeners indicated a higher intelligibility rating for
artificial larynx
speakers
than the
esophageal
the
speakers.
Esophageal speech was ranked by 60% of the listeners as
least pleasant of
three methods of
study of message-to-competition
1982).
the
alaryngeal speech in
ratios (Clark and
a
Stemple,
Data from the Green and Hults study (1982) indicated
that of the following
speech methods--Tokyo pneumatic
the Servox electrolarynx,
laryngeal
speech--poor
preferred
on
aid,
poor esophageal speech, and normal
esophageal
voice
speech
quality,
was
the
pitch,
intelligibility, and rate by naive judges.
least
loudness,
As indicated
by
the previously stated results, a review of the literature on
comparisons between esophageal speech and artificial
speech indicates
two
methods.
differences in
As
stated
by
preferences between
Clark
and
to
differing
speaking
these
Stemple,
differences may be attributed to "differences among
relating
larynx
proficiencies
alaryngeal talkers, differing listening environments
these
studies
of
the
and/or
conditions, and different perceptions of the speech
as the result of differing preference-judgment
samples
instructions
provided (Clark and Stemple, 1982).
The
laryngectomee's perception of his speech is
influenced
the
by
situation.
listener's
When a
impression
in
to continue in other environments.
tries and
cannot be
frustration and
a
(Duguay, 1986).
understood,
is
on the part of the
practice speech
restaurant or
experiences
As Duguay states,
he
is apt
consequent diminished
Success
social
he is encouraged
to
achieved by
"if he
experience
desire
to
the use
appropriate speech aid for the individual and
-
the
laryngectomized individual
success with his new voice with a listener,
often
talk"
of
the
encouragement
clinician and his significant others
in different
in a
environments,
grocery store.
such as
Practicing
in
to
a
esophageal
and/or electrolarynx speech in various social situations
or
settings requires the laryngectomee
to
to adapt his speech
the environment.
The
laryngectomee must make adjustments for
communication due to differences
his new voice and
have
been
that of a
noted
in
effective
between the dimensions
laryngeal speaker.
intensity,
of
Contrasts
quality,
rate,
intelligibility, and frequency by several researchers.
The
average intensity
dB,
which is up
level of
to about
(Perry, 198.3).
esophageal voice
20-25 dB lower
is 40-50
than laryngeal
voice
The esophageal intensity range is only about
Intensity is
20dB, compared to 45 dB in the normal speaker.
related to
intelligibility;
"The apparent
voice is also a
function of the speaker's
(Duguay, 1986).
It has
of intensity improves
(Shanks,
tha quality of
vocal
esophageal voice are rough,
bubbly (Weinberg, 1986).
reduction
the alaryngeal
strain,
to
tense, wet,
and
Weinberg and Bennett (1973)
that the most frequent complaint of listeners of
speech
is
abnormal
difference among
quality
voice
the average
good
have a
the rate of
This
has not
population
at a
or
rate
speakers
significantly
intelligibility
1983).
to decrease
one to two octaves
been
correlated
the pitch of
for the
lower (Shanks, 1986).
with
intelligibility
alaryngeal or laryngeal speakers (Hyman, 1986).
in
speech.
average
Although
the frequency of alaryngeal speech is typically lower,
has not
the
stated
intensity
for the average male,
lower and
of
As
intelligibility of alaryngeal
one octave
of
assumption
esophageal
yet been
(Salmon,
suggested
In the area of frequency,
female,
reads
this translates to the
laryngectomized
esophageal voice is
and
whereas
acceptability
order to improve the
laryngeal
of 150-165 words per minute,
correlated with
has been
the
Another
average
speaking situation,
lower rate.
esophageal
1986).
speech.
esophageal speaker
a normal
earlier, it
of
state
The
80-130 words per minute;
that in
(Hyman,
attributes
alaryngeal speaker is in
adult reads at a rate
voice
attributed
qualities
hoarse,
a
intelligibility"
also been noted that the
Some
1986).
loudness of
in
this
either
These
contribute
speech.
differences in
to
In
the
attributes and
listener's
perception
a social interaction
other
of
factors
alaryngeal
study conducted by
Blood
and Blood, it was conclude that laryngeal individuals prefer
to
interact
with
handicap rather
laryngectomees
than
those
who
who
do
acknowledge
not.
The
perceived the acknowledging individual to be more
their
subjects
pleasant,
calm, active, likable, well-adjusted, stronger, tougher, and
hardworking on a bipolar
1982).
-
Blood,
In 1971, Hoops and Noll studied the effect of visual
aspects of
conclude
adjective scale (Blood and
esophageal speech
that
judgments
of
on listener
esophageal
perceptions
speech
based
and
on
audiovisual presentation differed significantly from ratings
based on auditory
Kushner, 1980).
by others in
or visual information
The laryngectomee's fear of being
social situations can
alaryngeal speech.
Youngstrom 50%
only (Hubbard
In a
of 72
patients
rejected
hamper his learning
study conducted
by Diedrich
who responded
stated
there were continuing social situations where they
intense embarassment over their speech.
and
of
and
that
suffered
Some of the factors
which help laryngectomees overcome these anxieties are their
sheer determination to
have no other
speak, their
choice, and
conclusions that
their resignation
best of it" (Diedrich, 1966).
to "make
they
the
METHODOLOGY
Subjects
Sixty
naive college-age listeners will be selected
subjects for the
study.
These students
will be
as
randomly
selected from a class (or classes) at Ball State University.
The students will have not had previous social contact
laryngectomized individuals.
with
Two speakers will be used--and
excellent esophageal speaker and an excellent
electro larynx
speaker.
Instrumentation
The proficiency of the two speakers will be judged by a
highly qualified speech-language professional.
Two
methods
of presentation will be used--audiotape and videotape.
The
students will rate the esophageal and electrolarynx speakers
using the Osgood
Semantic Differential.
bipolar adjectives,
they will
using a seven-point scale.
Using the set
rate each speaker
separately
Each presentation will
of the speaker counting from I
to 20,
of
consist
saying the months
of
the year, and reciting a short passage.
Procedure
Thirty
presented with
of
a
the randomly
selected students
2-minute audiotape
presentation
will
of
be
the
electrolarynx speaker and the esophageal speaker.
The other
thiry students will be
videotape
~
presented with a 2-minute
.-
presentation of the electrolarynx speaker and the esophageal
speaker.
The split half
the sequence
example,
for
subjects will
and
the
order
technique will be used to
effect in
audiovisual
view
the
experiment.
presentation,
the electro larynx
control
15
speaker
of
first;
For
the
the
other 15 subjects will view the esophageal speaker first.
Statistical Design and Analysis of Data
The statistical design to be employed will be the Anova
2x2 Test of Variance.
variables-the
This design will compare two sets
of
method
speech
(electrolarynx
esophageal) and the method of presentation (audiovisual
audio only)
-
--
as rated
by
naive college
student
using the Osgood Semantic Differential task.
of
and
and
listeners
RESULTS
Due
to
limited
presentation of
the
altered slightly.
two groups
of
varied using
time
audiotape and
the
method
audiovisual
tapes
Both tapes of each speaker were shown
students.
the
available,
The
"split-half"
order of
presentation
technique
to
control
of
was
to
was
for
sequence and order effects.
The
2-Way
Analysis of
Variance results
showed
an
initial F ratio of 12.55, which is significant at the
.01 level.
source of
Subsequent investigation
variation to
be the
showed
type of
the
primary
alaryngeal
speech
used, not the modality of recording (audio vs. visual).
~
The alpha for the degrees of freedom of (1,
the .01 level.
Results show
63) was
7.04 at
an F ratio of 33.97, which
is
significant at this level.
Overall
listener
satisfaction
was
computed
in
percentages.
The following are the calculated means of each
group:
(1. )
Audio only, esophageal speaker--69,
only,
electrolarynx
esophageal
speaker--79,
speaker--70,
(4.)
(2.) Audio
(3•)
Audiovisual,
Audiovisual,
electrolarynx
speaker--85.
A t-test
speech used.
was used to compare
the type of
On a t-test comparing the two types
audiovisually, the
t-test
statistic
was 4.56.
alaryngeal
presented
This
is
significant at the .01 level (alpha=2.701) with the
of freedom (1,
42).
This shows
a significant
degrees
difference
between the two types of speech using the audiovisual
modality of recording.
A t-test was also used
electrolarynx
presentation.
speakers
A
to compare the esophageal
within
t-test statistic of
the
audiotape
3.50 was
42).
only
calculated.
This is significant at the .01 level (alpha=2.701) with
degrees of freedom (1,
and
the
CHARTS
Source
d.F.
S.S.
M.S.
3
3685.48
1228.496
Listener
21
2307.15
109.86
Error
63
6168.26
Total
87
12160.89
A
Method
B
alpha for d.F. of (3, 63)
F
12. 547 1
97.908
2.75 (.05 level)
4.11 (.01 level)
Source
A
Audio vs
d.F.
S. S.
M.S.
1
219.55
219.55
2.24
1
3325.91
3325.91
33.97
1
140.01
140.01
1. 43
63
6168.26
F
Visual
B
Electro
v s. Es
Interaction
Error
alpha for d.F of (1, 63)
97.908
3.99 (.05 level)
7.04 (.01 level)
CONSENT FORM
You are invited to participate in a research project
concerning speech techniques used by laryngectomees,
individuals who have had their larynges removed due to the
effects of cancer.
This project investigates college
students' reactions to various types of alaryngeal speech
(speech without use of the larynx).
Your participation in this project will require you to
listen to an audiotape and/or to view an audiovisual tape of
two laryngectomees.
The tapes are less than five minutes in
length.
Following the presentation, you will complete a
questionnaire asking you to rate the speaker(s) according to
several attributes.
The presentation and questionnaire will
take you approximately fifteen minutes of your time.
You do not need to write your name on the
questionnaire.
All data collected in this study will be
kept anonymous.
There are no risks or ill effects from
participating in this project.
You are free to withdraw
from participation at any time.
You are also welcome to ask
any questions of the investigator before signing the Consent
Form and participating in the study.
INFORMED CONSENT STATEMENT
I,
, agree to participate in this
research project on alaryngeal communication.
This study
was clearly explained to me and any questions were answered
to my satisfaction.
Participant's Signature
-,
DIRECTIONS
Thank you for participating in this research project.
You will be guided through these simple instructions for
your participation.
For each laryngectomee that you see and/or hear on tape
you will be asked to fill out a questionairre.
The
questionairre consists of thirty items.
Each item is a pair
of attributes that each person may possess to a certain
degree.
The pairs are separated by a continuum of seven
blanks.
Think of these seven blanks as a continuous line
from one end of the extreme to the other.
You are asked to
place a check mark on the blank from 1 to 7 which most
closely matches your impression of this laryngectomee.
For each pair of items you should have a check mark
somewhere between blank 1 and blank 7.
Please complete the
entire questionnaire.
Respond with your first instincts, as
they usually most accurately reflect your impression of the
speaker.
Your help on this project is greatly appreciated.
If you have any questions, please feel free to ask the
investigator.
-.
DISCUSSION
With this group
of naive
listeners,
the
individual
using electrolarynx speech was viewed with an overall higher
level of satisfaction than the esophageal speaker.
This
supported by the results of the 2-Way Analysis of
Variance,
t-tests, and the calculated means of each group.
be
several
reasons
loudness level,
vision,
and
for
this;
microphone
tape
age,
general
placement
recorder
There
field
(listener).
significant difference was found between the two
of recording (audio only vs.
speakers,
the
primary
audiovisual).
source
of
related to the actual speakers.
may
appearance,
observer
placement,
of
No
modalities
With these
variation
is
was
two
directly
Calculations indicate
this
variation may be due to the type of speech used.
In order
to limit speaker variations, it is
suggested
that one speaker be used who is proficient in both types
alaryngeal
speech.
This
would
eliminate
of
personal
differences between speakers which may be evident from audio
and/or audiovisual recordings.
listeners
may
Research in
also
add
this area
An increase in the number of
credibility
using a
to
these
more diverse
findings.
age group
of
listeners may give an accurate representation of the average
social impression
significant
of
the
information
pathologists,
related fields.
and
general public.
for
alaryngeal
professionals
in
This
speakers,
medicine
and
may
be
speech
other
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