Objectives: This study aimed to examine the discriminative ability of the Korean-Specific Expanded Controlled Oral Word Association Test (KSE-COWAT), which reflects linguistic characteristics of the Korean language, and to investigate its neurophysiological validity by measuring prefrontal cortex activation using functional near-infrared spectroscopy (fNIRS). Methods: Participants were 49 individuals with subjective cognitive decline (SCD) with normal cognitive function, and 50 individuals with mild cognitive impairment (MCI). Results: (1) In the Initial-syllable, final-syllable, onomatopoeia, Ideophone, orthographic constraint, and orthographic letter fluency tasks, the MCI group produced significantly fewer correct responses than the SCD group. (2) During the verb inflection fluency task, the MCI group showed significantly greater activation than the SCD group. (3) Significant prefrontal activation was observed in the left orbitofrontal cortex (OFC) during the phonemic fluency task, the left dorsolateral prefrontal cortex (DLPFC) during the Two-syllable orthographic fluency task, and the bilateral OFC during the orthographic letter fluency task. Conclusion: The findings of this study suggest that the language and executive functions required vary according to the characteristics of the language task, which may consequently affect the discriminative ability between individuals with SCD and those with MCI. In addition, the findings suggest that prefrontal cortical activation increases as a compensatory mechanism during the process of cognitive decline. Furthermore, the combined use of the KSECOWAT and fNIRS may serve as a useful approach for the early identification of cognitive decline and the development of intervention plans.
Objectives: This study investigated the effects of lexical factors and noise load on lexical access in typically developing (TD) children and children with speech sound disorders (SSD) to compare their underlying phonological characteristics. Methods: Twenty-four TD children and 21 children with SSD completed a lexical access task under four conditions crossing word frequency (high/low) and average neighborhood frequency (high/low). Accuracy rates, error type rates, first and final syllable onset times, and correlations between task performance and language and speech accuracy abilities were analyzed. Results: Children with SSD showed significantly lower accuracy than TD children, though both groups exhibited higher accuracy under high word frequency and high average neighborhood frequency conditions. Regarding error patterns, the SSD group showed significantly more initial syllable errors under high average neighborhood frequency conditions and more whole-word errors under low average neighborhood frequency conditions. Conversely, the TD group showed more lexicalization errors under high average neighborhood frequency and more final syllable errors under low average neighborhood frequency. Final syllable onset time was earlier with higher word frequency, but this effect was significant only under high average neighborhood frequency conditions. Correlation analyses revealed that expressive language scores and revised consonant accuracy had significant positive relationships with accuracy across all conditions. Conclusion: These findings indicate that children with SSD possess unstable underlying phonological representations, leading to limitations in cognitive resource allocation during neighborhood competition under noise loads, resulting in frequent lexical access failures.
Objectives: This study investigated the effects of the ‘Metaphon Phonics’ program, integrating minimal pairs, Metaphon, and phonics, for first- and second-grade children with speech sound disorders (SSD) accompanied by reading difficulties (RD). The program emphasized the percent consonants correct (PCC) of late-developing phonemes prone to persistent errors and incorporated both word- and ejeol-level decoding activities. Furthermore, telepractice was applied to overcome geographic barriers and improve access to speech-language pathology services. Methods: A 10-session online intervention was conducted for 14 children with SSD accompanied by RD in the Chungbuk area. The participants were assigned to levels 1 or 2 to receive customized programs based on their initial decoding abilities. To evaluate the program’s effects, pre- and post-intervention, late-developing phoneme PCC and step-by-step decoding assessment scores were compared. Results: The late-developing phoneme PCC and decoding scores for all participants improved significantly, demonstrating a large effect size. These results indicate that improvement in both domains was achieved despite the relatively short intervention period and the characteristics of the online environment. Conclusion: This study demonstrated that integrating phoneme discrimination through minimal pairs, speech sound awareness through Metaphon tasks, and grapheme-phoneme mapping through phonics can maximize the mutual facilitation of spoken and written language in a short period. These findings are significant as they provide an efficient intervention approach for children with SSD accompanied by RD and confirm that online platforms offer sufficient clinical efficacy, overcoming the limitations of face-to-face intervention.
Objectives: This study aimed to investigate the perceptual speech characteristics of healthy older adults by comparing speech intelligibility, listening ease, and speech acceptability across speakers in their 60s, 70s, and 80s. Furthermore, the study examined the relative influence of voice quality and prosody on overall speech acceptability to provide an evidence-based foundation for age-tailored clinical interventions. Methods: Ninety healthy older speakers, equally divided into three age groups (60s, 70s, and 80s), participated by making recordings while reading a standardized reading paragraph. Twenty general adult listeners evaluated the recordings. Speech intelligibility was calculated as the percentage of correctly transcribed words. Listening ease and speech acceptability—including sub-dimensions of voice and prosody—were rated on a 5-point Likert scale. Data were analyzed using MANOVA, Pearson correlation, and stepwise multiple regression. Results: While speech intelligibility and listening ease did not differ significantly across age groups, speech acceptability significantly decreased as age increased. Intelligibility correlated with listening ease but showed no significant relationship with acceptability. Notably, the primary predictors of acceptability shifted by age: prosody for the 60s; both voice and prosody for the 70s; and voice quality exclusively for the 80s. Conclusion: The findings suggest that intelligibility and acceptability are distinct perceptual dimensions in aging speech. Clinical assessments should incorporate multidimensional measures beyond simple intelligibility. Interventions should employ age-specific strategies, focusing on prosodic naturalness for the ‘young-old’ and prioritizing voice quality for the ‘oldest-old’ to enhance social communicative competence.
Objectives: This study aimed to compare narrative comprehension abilities between typically developing children and children with specific language impairment (SLI) according to narrative production conditions, an individual factor influencing narrative processing. In addition, the relationships between narrative comprehension and working memory were examined. Methods: Narrative comprehension and working memory were assessed in typically developing children and children with SLI under two narrative production conditions: story generation and story retelling. The collected data were analyzed using a twoway mixed analysis of variance (ANOVA) and Pearson product-moment correlation analyses. Results: Typically developing children performed significantly better than than children with SLI in both literal and inferential comprehension. Significant interaction effects between group and narrative production condition were found for both types of comprehension, with larger group differences observed in the story retelling condition. Working memory was significantly associated with narrative comprehension, and the patterns of association differed according to comprehension type and group. Conclusion: The findings suggest that children with SLI experience greater difficulty during story retelling due to limitations in working memory resources. In contrast, the story generation process may facilitate subsequent narrative comprehension by activating story schemas and supporting the organization of narrative information. These results highlight the important role of working memory in narrative comprehension and suggest that story generation may be a useful intervention strategy for improving narrative comprehension in children with SLI.
