Lecture Thirteen Fluency problems in aphasic and Down syndrome speakers

1
Lecture Thirteen - Fluency problems in aphasic
and Down syndrome speakers
Orienting Question Compare and contrast
stuttering, aphasic and Down syndrome speech
2
In the first part, look at stuttering and aphasia
together. Why?

• Stuttering is a problem in development
• No major organic cause
• Aphasia is a problem of senescence
• Has a clear organic cause

3
Answer - both affect function and content words
in different ways

• Function words
• pronouns, articles, prepositions, conjunctions
  and auxiliary verbs
• Content words
• nouns, main verbs, adverbs, and adjectives
• Stuttering
• Function words are repeated as wholes or there
  are pauses around them
• Content words are more likely to involve parts of
  words
• Aphasia
• Function words omitted or substituted
• Content words lose their inflectional endings

4
Short extract of stuttered and aphasic speech to
illustrate these things The dog which you gave
me is barking Stuttering The, the, the dog
which you gave me is b.b.b.barking Aphasia Dog
give bark
5

• A variety of explanations have been offered for
  both sets of
• observations, some suggest that they arise at the
  same linguistic level
• Stuttering
• Wijnens (1990) Development of the Formulator
  Hypothesis predicts that the
• development of serial order planning and
  incorporation of closed-class elements
• function words into the expressive grammar
  precipitates developmental patterns of
• disfluency. Bernstein Ratner, 1997
• 2. - Dayalu et al. (2002) Study on isolated words
  that showed higher stuttering rates
• on content than function words, suggests all
  disfluencies are mediated by word frequency
• Aphasia
• Grodzinsky cross linguistic pattern of problems
  in aphasic patients interpreted as
• grammatical effect
• 2. Stemberger (1985) attributes omissions,
  substitutions, phonological errors as due to
• word frequency

6
a. If the two disorders are affecting the same
mechanism, then got to account for how function
and content words are affected in the different
way we saw earlier b. Alternatively, it is
possible that though both are expressed on
function and content words, nevertheless this
reflects problems at different levels because
function and content words are processed
differently at several levels.
7
Example Aphasia affects syntax Function/content
differences arise because they play a different
grammatical role Stuttering affects lexical
level Function/content differences arise because
they play a different lexical role Even so
(case b) models need to permit both to occur Put
another way, explanations that relate the
problems seen in the two disorders re fluent
speech afford a strict test of theory
8
evidence to see what level function/content occur
for each disorder

• Semantics -used in Browns account
• no studies examined imagery/concreteness
• Syntax
• seen Wijnen view, a position Bernstein Ratner
  favors too
• in authoritative reviews, Nippold finds no
  support
• Morphology
• only two studies word end morphology
• Chloe Marshall and Rachel Diment
• neither find any effect of word endings on
  stuttering

9
Marshall Study
Inflections Plural marking on nouns
(the cat, the cats) N Tense (I lie, you like, I
lied, you lied) V Agreement V Aspectual
V Generated phonol x morphol
simple/complex No effect end cluster, no effect
inflectional morphology
10
Prosody plenty of acoustic-phonetic work shows
prosody Implicated linguistic link Selkirks
prosodic words (PW) Single content word and
function words as satellites Points about
PW stuttering (stalling in particular) only on
initial function words Not syntax in all
cases Draw on PW later
11
Lexical Function and content words exhibit
different properties in their own right (and
even some evidence that subserved by different
CNS structures) Dayalu et al. (2002) get
different stuttering rates for words in
isolation Even for isolated words can start
uttering before plan complete Initial function
and content allow planning and execution taking
place at same time to be examined Their account
(word frequency) would not work for their
material very low frequency function words
included in their list
12
Lexical (continued) Neighbourhood density (or
words) Arnold et al. (2005) Example star has tar,
start, stir and spar as its neighbours Arnold et
al. (2005) used Dense gun, key, hat, pig,
sock Sparse heart, tree, start, fork,
spoon. Dense no consonants strings, sparse all
have consonant strings Is it number of word
neighbours or phonetic properties?
13
Lexical (continued) Age of acquisition Lexical
(here) not studied (has been controlled).
Surprising. (Ellis has looked at in
aphasics.) Phonetic has been examined see
below Grammatical category Work of Brown often
wrongly attributed as study of function/content
(Dayalu et al., 2002, Wingate 2003) Rank ordering
of difficulty by word type (will draw on these
data later)
14
Rank of difficulty of parts of speech based on
the median percent of stuttering for 32
individuals Data from Brown, S. (1937).
Participial adjectives Proper
nouns Gerunds Adjectives Adverbs Nouns Root
verbs (in verb phrase) Simple verbs Subordinating
conjunctions Relative pronouns Personal
pronouns Infinitives Coordinating
conjunctions Prepositions Auxiliary
verbs Possessive pronouns Articles Preposition
s linked to verbs
15
Semantic Aphasic subjects are better able to
name items higher in imageability/concreteness
as it is easier to access semantic information
of the target word that assists with word
retrieval (Ellis Young, 2002 Nickels, 1997).
Effects of imageability/concreteness have been
found in word repetition (Howard Franklin,
1988).
16
Syntax Grodzinsky, Swinney and Zurif (1985) give
the syntactic tree for the utterance the boy
looked for the cat, in bracket notation Lose
determiners and preposition for (function words),
and past tense on verb get boy look cat.
Contrasts with Kean (1977) and Caplans
analyses Kean (who seems to be arguing for a
phonological characterization with similarities
to our account of content word influences) is
dismissed as it cant handle non-concatenative
morphologies like semitic ones. This is a
particular thing I could ask Marias help
on. Caplan argues only retain NP VP etc. But
they argue VP (at least) is broken down into V
INFL (their data). Debate how to do, but few
doubt syntactic effect
17
Morphology Past tense (V) rarely retained, while
the present participle ing (V) and plural s (N
I suppose check) are retained. Refs de
Villiers 1974 and Gleason 1975. Prosody Not
looked at in detail (PW not used for instance)
though there is a study by Goodglass on sentence
position and stress which considers effect of
context on omission of grammatical morphemes
that I need to look at.
18
Lexical Garrett considers that the different
performance on function and content words by
aphasics arises because these word types are
processed in different ways The main processing
differences summarized by Tissot et al. (1973)
are 1. loss of function words, 2. predominance
of nouns in preference to verbs, 3. loss of verb
inflection, 4. loss of agreement of person,
number and gender.
19
Lexical (continued) Neighourhood density Not
looked at Age of acquisition Lexical Ellis
claims important (impression I get is that this
is marginalised?) Phonetic not read anything so
far (is Blumstein just perceptual work?)
20

• Lexical (continued)
• Grammatical category
• Loss of different types of function words.
  Analysis of omission
• rates of different types of function words are
  reported in
• Miceli et al., 1983 and Kolk et al., 1982 (in
  agreement).
• Order of omission
• determiners (if these are articles, 2nd from
  bottom
• of stuttering list),
• - auxiliaries (4th from bott),
• - prepositions (last),
• - pronouns (3rd)
• - connectives (coordinating conjunctions, 6th
  from bottom).
• Draw on easiest for PWS lost first by aphasics
  later

21
Summary Clear effects syntax and morphology.
Phonetic and motor not formally
examined Different involvement of function and
content words at several different levels in
both disorders - stuttering weight towards
bottom end, and aphasic top end, of linguistic
processes. Model will have to allow several
levels to interact
22
A proposed explanation Figure 1. Activation
buildup representing two function words and a
content word. Absolute Activation Threshold

time
23
Figure 2. Activation buildup and decay
representing two function words and a content
word.
Absolute Activation Threshold
time
24
Figure 3. Activation and decay parameters for the
situation leading to stalling for a PW consisting
of a function word preceding a content word. The
solid lines represent the activation states for
the function word (left) and content word
(right) at the point where the speaker has just
finished uttering the function word. The dotted
lines indicate the activation for the content
word still has some way to go before it reaches
full activation. Stalling results in this case
because the function word has decayed but
activation is still greater than the activation
for the following content word and, consequently,
the function word is repeated.
Absolute Activation Threshold
time
25
Figure 4. Activation and decay parameters for the
situation leading to advancing for a PW
consisting of a function word preceding a
content word. The solid lines represent the
activation states for the function (left) and
content word (right) at the point where the
speaker has just finished uttering the function
word. The dotted lines indicate the activation
for the content word still has some way to go
before it reaches full activation. Advancing
results in this case because the function word
has decayed below the activation level of the
following content word and, consequently, the
content word is initiated even though it still
has some way to go before it reaches full
activation (indicated by the dotted line).
Absolute Activation Threshold
time
26
Down syndrome DS children are straightforward to
locate as they often attend special schools,
have other medical issues that need monitoring
and so on. The incidence of stuttering has
been reported to be up to around 50 (Devenny
Silverman, 1990 Preus, 1973). DS children are
reported to have a slow rate of development (as
a rule of thumb, development proceeds at about
half the rate of normally-developing children).
This means that the language development of DS
children can be studied at a later age of onset
and its development over a longer time course.
27
Demographics Approximately one in 1000 children
in the UK are born with DS (Steele, 1996). DS
onsets at birth and there is no chance of
recovery though medical and other health issues
can be effectively managed. Age profile There
is no information about onset and recovery of DS
children from stuttering. It seems to be assumed
that they will not show any recovery and
therapists see their role as helping the DS
child manage, rather than recover from their
stutter (Conture, 2001 Preus, 1990).
28
Genetics DS is a genetic condition caused by a
failure in the cell division process. In 1959
Jerome Lejeune tracked this down to chromosome 21
(the smallest chromosome). DS individuals have an
entire or partial extra copy of this chromosome.
There are three major types due to chromosomal
abnormality in cell division, translocation
(Robertsonian DS) and mosaicism. 95 of DS cases
involve problems in cell division. The disorder
is present in all races and risk increases with
maternal age. The environmental contribution is
not known and it is not known whether stuttering
in DS children follow the family history/
affected chromosome patterns seen in non-DS
children
29
Speech signs Three major issues a) whether
stuttering occurs in DS or not, b) whether the
form of stuttering is an age-appropriate form,
c) whether the DS children show other speech
signs that are not particular to stuttering.
30
Little data. Preus (1973, 1981) 47 DS speakers
out of 67. Whole-word, part-word repetitions and
prolongations were examined (corresponding
roughly to Ambrose and Yairis 1999, SLD
category), 46.8 were judged stuttering. If
whole-word dysfluencies were excluded (akin to
what Wingate, 2001 recommended) the frequency of
stuttering reduced to 34. Preus (1973)
considered that secondary symptoms such as body
movements, avoidance and postponement are signs
of awareness of stuttering and indicative of a
more advanced form. W hen only these signs were
included, 29.8 of the sample was still
considered to stutter which suggest that
stuttering in its advanced form can occur.
31
Bray (2003) conducted a small scale survey which
was sent to a group of about 180 therapists with
a special interest in stuttering in the UK.
Twenty-seven (15) responded by filling out a
questionnaire This provided informal indications
about the dysfluencies the therapists had seen
in DS children and the nature and success of
treatment they had offered to clients with DS of
all ages. The case load involved with clients
with DS was 1 for seven respondents, and most
(14) reported that DS made up around 9 on their
case load (http//www.stammering.org/downs_survey
.html).
32
The therapists in Bray (2003) provided
information about the identification of
dysfluencies by indicating which dysfluencies on
a list they saw most often in their clients.
Most therapists reported that the commonest
pattern of dysfluency was repetition of sounds
or syllables, next in order of occurrence were
hesitations and interjections, fixations and
blocks, struggle, prolongations of sounds or
silence, tension in muscles, broken words or
false starts, repetitions of phrases, and
embarrassment or concern. Most identified
dysfluencies are repetitions, blocks and struggle
behaviors all of which resemble stuttering. When
the data were classified into the SLD category
(Ambrose Yairi, 1999), Bray (2003) claimed
that nearly 90 of the identified features fell
into the SLD category.
33
Critique of Bray 1. Small-scale. 2. The
response rate of the special interest group was
low at 15 so the results might not be
representative even of the select group. 3.
There was no mention as to what sorts of
questions were included in the questionnaire,
whether there were definitions for the specific
types of stuttering behaviors so that all biases
about terminology could be eliminated and so on.
4. The data provided appear to be from memory
about cases. Therapists find difficulty agreeing
about stuttering (Kully Boberg, 1988), so, at
least, permanent recordings are needed to ensure
that there is no dispute about the judgment.
34
There are two suggestions in the literature which
imply that DS children show speech signs other
than stuttering. One is the loss of function
words which, we note, is often related to loss
of word-final inflectional endings. The other is
derived from a report by Preus (1981). Preus
stated that of 47 children with DS, 34 had
symptoms of stuttering while 31 had
dysfluencies similar to cluttering. The features
of cluttering include minimal awareness and
reaction to the dysfluency, intelligibility
difficulties and rapid speech rate. Besides
these few reports, there are many websites which
comment on dysfluency characteristics of DS
children that are related to stuttering. One
should be cautious about these as the opinions
given have not been scientifically scrutinized
and, so, may reflect the personal views of the
webmaster.
35
Development of language The production
vocabularies of DS children seem to be relatively
spared, at least compared to typically-developing
peers matched for mean length of utterance
(Miller, 1992). In a number of papers, Chapman
has emphasized the importance of the so-called
reception-production gap by examining the effect
of hearing loss on language development.
Chapman, Schwartz and Kay-Raining Bird (1991)
documented DS childrens poor comprehension
abilities. Chapman, Schwartz and Kay-Raining Bird
(1998) reported that age accounted for about
80, whilst hearing loss accounted for only about
7 of the variance in adolescents grammar
comprehension scores. Vicari, Caselli and
Tonucci (2000) examined lexical and
morphosyntactic development in 15 DS children
and 15 mental age-matched controls. They reported
no difference in lexical development, but
significantly poorer ability by the DS children
in terms of morphosyntactic processing. Eadie,
Fey, Douglas and Parsons (2002) performed a
similar study that compared DS, controls (this
time matched on mean length of utterance) and
SLI children. Problems were reported for both
the DS and SLI children for word-final
inflections. Chapman (1997) in her review
article, considered developmental theories of
the morphological deficit and how they might
apply to DS speech. Telegraphic speech refers
to loss of function word loss. DS speakers have
been reported to lose function words (Chapman,
1995 Fowler, 1995). Loss of function words and
inflectional endings go together in another
disorder, agrammatic aphasic speech (see Howell,
in press, for a recent discussion).
36
Language usage Memory deficits have been better
documented in DS children. Marcell and Weeks
(1988), for example, found verbal short term
deficits. These potentially have significant
implications for assessment of language
comprehension and production, particularly when
standardized procedures are used for testing
that require processing specific stimuli and the
stimuli are required to be memorized long enough
so the participant can provide an appropriate
responses. Clearly memory deficits may also be
contributing to behaviors that may be labeled as
inattention, or result in inconsistent response
patterns in other tasks too.
37
Audition DS children have small sinuses, narrow
canals in the middle ear and an increased risk of
respiratory infection. These are physical
characteristics all of which could lead to a
higher than average incidence of conductive
hearing loss (Lorenz, 1998). In line with this,
sixty to eighty percent of children with DS have
hearing deficits. Individuals with DS may have
sensorineural loss, conductive loss related to
otitis media, or both. DS children, unlike CWS,
have hearing losses as measured with standard
audiometric techniques (losses can also be
revealed using auditory brain stem responses and
otoacoustic emissions). Forty to 85 of DS
individuals have impaired hearing (Dahle
McCollister, 1986 Davies, 1996) and the
impairment is severe in 10 to 15 of these cases
(Davies, 1996 Marcell, 1995 Marcell Cohen,
1992). The standard audiometric techniques show
up conductive losses (which could derive from
OME). Sensorineural losses are also apparent in
20 o cases according to Lorenz (1998). OME could
make a contribution to the sensorineural loss
(Stephenson Haggard, 1992) though the losses
are so severe it is unlikely that this alone is
the cause. Some authors have claimed that up to
50 of DS children suffer from a conductive
hearing loss, due to OME (Lorenz, 1998).
38
Affective development Little evidence available
39
Summary of the major areas where differences have
been revealed between CWS (centre column) and DS
children (right-hand column). Attributes are
listed in the left-most column.
40
(No Transcript)
41
(No Transcript)
42
Summary and conclusions Aphasics and DS children
both show telegraphic speech. The explanations
offered for telegraphic speech in aphasics would
not apply to DS speakers. An alternative
explanation has been offered Other comparisons
between stuttering, DS and aphasia have been
offered
43
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