During the preschool period, children’s vocabulary expands rapidly while acquiring a variety of words. At this time, the ability to retrieve the words is an important variable when predicting language processing and learning ability in the following...
During the preschool period, children’s vocabulary expands rapidly while acquiring a variety of words. At this time, the ability to retrieve the words is an important variable when predicting language processing and learning ability in the following school age. Thus, it is important to explore elements that affect vocabulary retrieval for these groups. 'Syllable neighborhood density' and 'phonotactic probability' were proposed as the factors. ‘Neighborhood density’ means the number of words sharing a same phonological element. In Korea, it is mainly measured by the number of words with the same first syllable. The term 'phonotactic probability' refers to the probability that a sequence of sounds will occur in a lexical item. In syllable neighborhood density, it can affect the lexical stage that deals with the entire lexical representation, and in phonotactic probability, it can affect the sublexical stage that deals with the phonological representation. Domestic studies on these two elements are very rare, and even those studies are dominated by studies on adults. Therefore, the need for research on children is further emphasized.
Thus, this study attempted to examine the effect of syllable neighborhood size and phonotactic probability considering the word retrieval for children aged 5 and 6. 15 5-year-olds and 17 6-year-olds participated, and they were instructed to name a picture. The naming questions were produced based on the vocabulary list of the first level of vocabulary for Korean education by grade and the study of basic vocabulary selection for infants and young children. The two data as samples, a total of 1,747 vocabulary were calculated for each value of the syllable neighborhood density and phonotactic probability. Next, based on the median value, total of 4 conditions consist of pairs of the syllable neighborhood density high/low×phonotactic probability high/low conditions. The number of total items were 56, and 14 items for each condition. The task was conducted by looking at the pictures and quickly naming them.
The result of the study is as follows. There were no significant effects of syllable neighborhood density in the reaction time. However, the high phonotactic probability, in other words, the common phonotactic condition, showed a significantly faster response than the rare phonotactic condition. In the positive response score analysis, there were no significant effect of individual elements, but there was a significant interaction effect between the syllable neighborhood density and the phonotactic probability. This showed the highest positive response score when interacting with fewer neighbors×common phonotactic probability and many neighbors×rare phonotactic probability, respectively. Lastly, when analyzing the correlation between vocabulary and each of the 4 conditions, a significant positive correlation was found with 3 conditions and expressive vocabulary. Individually, a significant positive correlation appeared with the expressive vocabulary in the condition of many neighbors and common phonotactic condition.
As a discussion of these results, the advantages of common phonotactic in reaction time can be confirmed. Moreover, it can be inferred that there are no significant effects of syllable neighborhood density for children who do not yet possess sufficient number of lexical representations compared to adults. Furthermore, it can be suggested that the necessity of considering the interaction between neighborhood density and phonotactic probability, and the possibility that abundant vocabulary can act as promotion, especially in the condition of many neighbors and common phonotactic. Therefore, by utilizing these results, it can contribute to a more systematic composition of difficulty when making questionaries for the picture naming tests and selecting treatment vocabulary.