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www.speechpathologyaustralia.org.au
JCPSLP
Volume 15, Number 1 2013
23
Acknowledgments
Thank you to all of the participants in the study and their
families. I additionally thank Jessica Barlow for all of her
guidance, mentoring, and support, as well as Sonja Pruitt,
Eric Bakovi ´c, Rachel Mayberry, and Vic Ferreira for their
comments on earlier aspects of this work. This research
was supported in part by a National Institute on Deafness
and Other Communication Disorders training grant, an
American Speech-Language-Hearing Foundation New
Century Scholars Program Doctoral Scholarship, and the
Sheila and Jeffrey Lipinsky Family Doctoral Scholarship.
References
Andrews, N., & Fey, M. (1986). Analysis of the speech of
phonologically impaired children in two sampling conditions.
Language, Speech, and Hearing Services in Schools
,
17
,
187–198.
Arnold, H. S., Conture, E.G., & Ohde, R. N. (2005).
Phonological neighborhood density in the picture naming
whether ND may simply cease to influence production at
the phonological level at a certain age due to more
influential factors (e.g., phonotactic probability).
Experimental studies should also be conducted with
different clinical populations such as children with word-
finding impairment in order to examine any performance
differences.
Conclusion
In conclusion, this study found that preschool children
retrieved the lexical-semantic representations of words with
high ND more accurately than those with low ND. This
revealed a facilitative nature of the lexicon in terms of
semantic
accuracy. A similar result was found regarding
phonological
accuracy; words with high ND were
articulated with a greater degree of accuracy than those
with low ND. As such, the degree of phonological similarity
in the lexicon appears to impact preschoolers’ production
accuracy both at the lexical and phonological level.
Appendix A. Experimental stimuli
Low neighbourhood density words Neighbourhood density
High neighbourhood density words
Neighbourhood density
wagon
1
drum
11
guitar
1
water
11
brother
3
feather
12
chicken
3
ladder
13
finger
3
shower
13
flower
4
cloud
14
judge
4
lemon
14
twins
5
teeth
14
queen
7
green
16
brush
8
plate
17
space
8
jeep
20
father
8
vase
21
knife
9
zoo
36
three
9
toes
41
snail
9
nail
42
Appendix B. Experimental stimuli control
Variable
Means (SD): low neighbourhood
Means (SD): high neighbourhood Statistic
density stimuli
density stimuli
Word frequency
1
106.67 (174.26)
58.40 (117.41)
t
(28) = 0.89,
p
= 0.38,
d
= 0.32
Positional segment frequency
0.22 (0.07)
0.22 (0.06)
t
(28) = 0.16,
p
= 0.87,
d
= 0
Biphone frequency
0.004 (0.004)
0.003 (0.003)
t
(28) = 0.96,
p
= 0.35,
d
= 0.28
Number of phonemes
4.07 (0.65)
3.60 (0.74)
t
(28) = 1.77,
p
= 0.08, d = 0.67
Number of syllables
1.47 (0.52)
1.33 (0.49)
t
(28) = 0.73,
p
= 0.47,
d
= 0.27
Imageability
612.40 (43.35)
608.33 (79.06)
t
(17) = 0.14,
p
= 0.89,
d
= 0.06
Familiarity
365.50 (101.02)
377.44 (148.45)
t
(17) = 0.21,
p
= 0.84,
d
= 0.09
Visual complexity
51.35 (26.85)
41.61 (25.35)
t
(28) = 1.02,
p
= 0.32,
d
= 0.37
Age-of-acquisition
3.94 (2.18)
4.04 (1.46)
t
(15) = 0.11,
p
= 0.90,
d
= 0.05
1
Note
. While the means for word frequency appear different, upon further inspection it was determined that one word with low ND had a very
high word frequency value; when this word was omitted, the average word frequency for words with low ND was 59.73, and the average word
frequency for words with high ND was 58.40, helping to explain the lack of significant difference reported here.