Background: There is a critical need for tests of auditory discrimination for young children
as this skill plays a fundamental role in the development of speaking, prereading,
reading, language, and more complex auditory processes. Frequency discrimination is
important with regard to basic sensory processing affecting phonological processing,
dyslexia, measurements of intelligence, auditory memory, Asperger syndrome, and specific
language impairment.
Purpose: This study was performed to determine the clinical feasibility of the Pitch Discrimination
Test (PDT) to screen the preschool child’s ability to discriminate some of the acoustic
demands of speech perception, primarily pitch discrimination, without linguistic content.
The PDT used brief speech frequency tones to gather normative data from preschool
children aged 3 to 5 yrs.
Research Design: A cross-sectional study was used to gather data regarding the pitch discrimination
abilities of a sample of typically developing preschool children, between 3 and 5
yrs of age. The PDT consists of ten trials using two pure tones of 100-msec duration
each, and was administered in an AA or AB forced-choice response format.
Study Sample: Data from 90 typically developing preschool children between the ages of 3 and 5
yrs were used to provide normative data.
Data Analysis: Nonparametric Mann–Whitney U-testing was used to examine the effects of age as a continuous variable on pitch
discrimination. The Kruskal–Wallis test was used to determine the significance of
age on performance on the PDT. Spearman rank was used to determine the correlation
of age and performance on the PDT.
Results: Pitch discrimination of brief tones improved significantly from age 3 yrs to age
4 yrs, as well as from age 3 yrs to the age 4- and 5-yrs group. Results indicated
that between ages 3 and 4 yrs, children’s auditory discrimination of pitch improved
on the PDT. The data showed that children can be screened for auditory discrimination
of pitch beginning with age 4 yrs.
Conclusions: The PDT proved to be a time efficient, feasible tool for a simple form of frequency
discrimination screening in the preschool population before the age where other diagnostic
tests of auditory processing disorders can be used.
Key Words
auditory processing disorder - discrimination - intelligence - language - reading
- speech perception
