BackgroundSemantic fluency tasks are widely used to assess lexical - semantic retrieval in healthy aging and aphasia; however, growing evidence indicates that semantic organization is influenced by culturally grounded lexical experience. Prior cross-linguistic work suggests that Korean speakers rely on culture-specific semantic schemas - such as zodiac animals - during animal fluency, yet it remains unclear how such differences manifest in retrieval strategies or semantic network structure in aging and aphasia.AimsThe current study investigated cross-linguistic differences in clustering, switching, and semantic network structure during animal fluency in English- and Korean-speaking older adults (OA) and persons with aphasia (PWA).Methods & ProceduresParticipants included English- and Korean-speaking OA (n = 30) and PWA (n = 67). All participants completed a one-minute animal fluency task. Clustering and switching were computed using SNAFU, and group-level semantic networks were constructed using co-occurrence - based Semantic Network Analysis. Global graph metrics - average shortest path length (ASPL), clustering coefficient (CC), and modularity (Q) - were compared across language groups.Outcomes & ResultsBehaviorally, English- and Korean-OA produced comparable total number of correct responses; however, English-OA generated significantly larger cluster sizes than Korean-OA. In PWA, English speakers produced significantly more correct items and significantly more switches than Korean speakers. Semantic network analyses revealed that Korean-OA networks demonstrated significantly longer ASPL, significantly lower CC, and significantly higher Q relative to English-OA. In PWA, Korean speakers also exhibited significantly longer ASPL than English speakers, indicating reduced global connectivity. Together, these results demonstrate that significant cross-linguistic differences in semantic network structure are evident in healthy aging and remain observable in aphasia.

Abstract Accurate language assessment is essential in clinical and research contexts. However, most assessment tools and questionnaires have been developed within monolingual frameworks, overlooking the particularities of the vast multilingual population and, thus, often leading to misdiagnosis and inequitable care. Here, we examine the limitations of monolingual‐centric approaches to language testing in multilinguals with acquired and progressive neurogenic disorders and explore the implications of multilingualism across linguistic, cognitive, neural, clinical, and sociocultural domains. We also address the need for technological innovation and theoretical refinement to better accommodate linguistic diversity in healthcare. Ultimately, we advocate for a nuanced, equitable, and culturally sensitive model of language assessment that reflects the realities of multilingual populations by accounting for their diverse linguistic repertoires, cognitive trajectories, and neural profiles. This model integrates valid, adapted tools, inclusive normative data, and context‐appropriate testing practices, with particular attention to under‐represented and typologically diverse languages.

PURPOSE:This study examined the effects of aging on the comprehension of simple comparative sentences in a predicate-final language. Additionally, we explored individual variability among older adults by categorizing them based on chance-level performance. METHOD:A total of 221 participants completed a sentence-picture matching task involving simple comparative constructions, which were manipulated by word order (comparee-first, standard-first). Response accuracy and response time (RT) were analyzed across age groups (young, old) and performance group within older adults (above-chance, chance). RESULTS:For age group comparisons, significant effects of group and word order emerged in RT. Young adults responded significantly faster than older adults in both word orders, with a larger group difference observed for comparee-first than for standard-first constructions. For both age and performance group comparisons, a significant interaction between word order and working memory (WM) scores emerged in RT. Participants with higher WM scores showed faster responses to comparee-first constructions, suggesting that cognitive resources play a role in processing syntactically complex comparative structures. CONCLUSIONS:The current findings indicate that age-related differences in sentence processing can arise even in comparatively simple syntactic forms, revealing their sensitivity to cognitive aging. Importantly, the observed interplay between WM capacity and syntactic structure highlights the necessity of integrating both cognitive and linguistic dimensions in psycholinguistic models of sentence comprehension across the adult lifespan.

Objectives: This study investigated age-related differences in behavioral performance and prefrontal hemodynamic responses during noun, verb, and letter verbal fluency tasks (VFTs), with a particular focus on identifying task types and neural regions that are most sensitive to aging. Methods: Ten young adults and eleven cognitively healthy older adults completed noun, verb, and letter fluency tasks while prefrontal cortical activity was measured using functional near-infrared spectroscopy (fNIRS). Behavioral performance was quantified as the number of words generated. Hemodynamic responses (ΔHbO) were analyzed using permutation-based mixed-effects ANOVA. Stepwise discriminant analysis with permutation testing and bootstrapping was used to determine which fluency task best differentiated age groups. Correlations between behavioral performance and prefrontal activation were examined separately for each group. Results: Older adults generated fewer words than young adults across all fluency tasks, with noun fluency yielding higher output than verb and letter fluency in both groups. Discriminant analysis identified verb fluency as the strongest behavioral marker differentiating older and young adults. At the neural level, ventrolateral prefrontal cortex (VLPFC) activation was greater than anterior prefrontal activation across groups, but older adults exhibited significantly reduced ΔHbO responses in the VLPFC. Additionally, verb fluency performance was positively correlated with right VLPFC activation in the older group only. Conclusion: These findings indicate that verb fluency is particularly sensitive to age-related changes in lexical retrieval and that reduced engagement of the ventrolateral prefrontal cortex characterizes verbal fluency performance in healthy aging.

Objectives: This study aimed to examine the effects of emotional valence (positive or negative) in contextual sentences on non-word learning in older adults. Specifically, it sought to determine whether emotional context could sensitively reflect cognitive differences between older adults with Mild Cognitive Impairment (MCI) and cognitively healthy controls. The study further explored the potential of emotion-based learning tasks as tools for early detection and intervention in cognitive decline. Methods: Thirty-one Korean-speaking older adults (15 with MCI, 16 cognitively healthy controls) participated in the study. Participants were asked to infer the meanings of non-words embedded in emotionally valenced sentences and to judge whether the non-words matched the meanings of actual words. Accuracy and reaction time were recorded as primary measures of performance. Results: The MCI group showed overall lower accuracy and slower responses compared to the control group.The control group demonstrated higher accuracy in positive contexts, while the MCI group showed minimal performance differences across emotional contexts. In the control group, greater accuracy was associated with faster reaction times, suggesting efficient cognitive processing. In contrast, in the MCI group, working memory was significantly related to task performance only in negative contexts. Accuracy in positive contexts was the key variable distinguishing the two groups. Conclusion: Positive emotional context appears to facilitate non-word learning and serves as a sensitive marker for early cognitive decline. These findings highlight the potential of emotion-based language tasks for early screening and intervention in aging populations.

Objectives: Discourse assessments are widely used in clinical settings to identify cognitive and linguistic impairments associated with normal aging and neurogenic communication disorders. Because richer spontaneous speech facilitates more reliable discourse analysis, effective methods for eliciting naturalistic language are needed. As the social roles of robots expand, their potential as tools for language and cognitive assessment has gained increasing attention. This study examined whether a conversational robot elicits greater discourse production and conversational engagement in older adults compared to a tablet and explored the clinical usability of robots as tools for discourse-based assessment. Methods: Fourteen healthy older adults participated in unstructured conversations on three daily topics with both a robot and a tablet. The robot incorporated non-verbal backchannel behaviors, such as nodding and facial expressions, and interacted with older adults using the ChatGPT model, while the tablet offered only verbal communication. Five linguistic measures were analyzed, including turn-taking frequency, total and mean utterances, and total and mean speech duration. Following each condition, participants completed a selfreport survey assessing usability and interaction experience. Results: Results showed that older adults produced significantly more total and mean utterances when interacting with the robot. Additionally, participants reported a greater sense of encouragement to engage with the robot. Conclusion: These findings suggest that the robot’s physical embodiment and interactive behaviors enhance conversational engagement, making it a clinically promising tool for eliciting spontaneous speech and collecting discourse data for language and cognitive assessment in aging populations.

PURPOSE:This cross-linguistic study investigates how healthy aging affects sentence comprehension across three typologically distinct languages-English (head-initial), Korean, and Japanese (both head-final). It explores how syntactic word order and semantic plausibility interact with aging and whether these effects differ across languages with varying structural characteristics. METHOD:A total of 290 adults participated: 103 English speakers (49 younger, 54 older), 98 Korean speakers (50 younger, 48 older), and 89 Japanese speakers (43 younger, 46 older). All participants completed a sentence-picture matching task using auditorily presented stimuli. The sentences were systematically manipulated for semantic plausibility (plausible vs. less plausible) and word order, contrasting instrument-first (instrument-theme) and theme-first (theme-instrument) structures. RESULT:Aging effects were observed across all languages, with older adults performing worse than younger adults. Across language groups, participants showed better performance for instrument-first sentences than for theme-first sentences. Semantic plausibility interacted significantly with age across all languages in both accuracy and response times, indicating that older adults were disproportionately affected by reduced plausibility. In contrast, word order effects were largely similar across age groups, although a significant Age Group × Word Order interaction was observed in response times for the Japanese participants only. CONCLUSIONS:This study demonstrates that systematic manipulations of simple sentence structures can effectively expose age-related and cross-linguistic differences in sentence processing. The findings illuminate both universal patterns of cognitive aging and language-specific parsing mechanisms, informing the design of sensitive and typologically flexible tools for assessing cognitive-linguistic decline.

PURPOSE:This study examined the structural comparability of the English and Korean versions of the Boston Naming Test (E-BNT and K-BNT) and evaluated whether structural similarity translates into comparable performance patterns in individuals with aphasia. METHOD:In Study 1, we analyzed two psycholinguistic features-lexical frequency and syllable length-across the E-BNT and K-BNT. In Study 2, 38 monolingual individuals with aphasia (19 English- and 19 Korean-speaking), matched on demographic and severity variables, completed the test. Overall accuracy and cluster-based item performance were compared across groups. RESULTS:Study 1 revealed no significant differences in lexical frequency between versions, although the K-BNT contained longer syllabic forms. In both versions, lexical frequency was strongly associated with item order, supporting a preserved graded difficulty structure. Study 2 showed comparable overall naming accuracy across groups but a significant Language × Cluster interaction. In English, lower frequency clusters showed progressively stronger associations with aphasia severity. In Korean, severity associations were observed for mid- and high-difficulty clusters, including culturally salient items, but did not follow the same monotonic gradient. CONCLUSIONS:The findings support broad structural comparability between the E-BNT and K-BNT while demonstrating that item-level contributions to severity may differ across languages. These results inform cautious cross-linguistic research comparisons and underscore the importance of considering cultural and linguistic factors, particularly in bilingual contexts. SUPPLEMENTAL MATERIAL:https://doi.org/10.23641/asha.32351364.

Hearing and vision impairments are modifiable risk factors for cognitive decline, yet their longitudinal contributions to mild cognitive impairment (MCI) and dementia remain unclear. This study examined differential associations of baseline sensory function and longitudinal sensory trajectories with cognitive status at Wave 9. Nine waves of data (2006-2022) from the Korean Longitudinal Study of Aging were analyzed, including 11,146 participants aged 45 years and older. Parallel process latent growth modeling was used to examine associations between baseline hearing and vision, their rates of change over time, and cognitive status at the final wave (cognitively normal, MCI, dementia). More rapid hearing decline was significantly associated with a higher likelihood of being classified in the dementia group. Poorer baseline vision was associated with a higher likelihood of being classified in the MCI group. In contrast, baseline hearing and longitudinal vision decline were not significantly associated with MCI or dementia classification, respectively. These findings indicate that longitudinal hearing decline shows a stronger association with dementia classification than visual impairment, whereas poorer baseline visual function may be more strongly associated with earlier-stage cognitive status.

PURPOSE:This study examined cross-linguistic and cross-cultural influences on picture-based narrative performance in Korean and English speakers with and without aphasia. We evaluated whether pro-drop-adjusted main concept (MC) scoring accounts for linguistic effects, identified picture-driven cultural effects on discourse, and examined associations between aphasia severity and performance. METHOD:Narratives were elicited with two AphasiaBank stimuli-Cat Rescue and Refused Umbrella-from 54 neurotypical adults (27 Korean neurotypical adults [K-NA], 27 English neurotypical adults [E-NA]) and 34 persons with aphasia (17 Korean persons with aphasia [K-PWA], 17 English persons with aphasia [E-PWA]). In addition to the original MC scoring criteria, we adapted the framework by developing a pro-drop adjustment that credited omitted but contextually recoverable arguments. Language and picture effects were examined under both MC criteria, whereas clinical group effects were evaluated using the adjusted criteria. Additional analyses identified MCs distinguishing language groups and examined associations with Aphasia Quotient (AQ). RESULTS:With original scoring, neurotypicals showed language (K-NA < E-NA) and picture effects (Cat Rescue < Refused Umbrella). After pro-drop adjustment, group differences were observed only for Cat Rescue and persisted when PWA were included. The main storyline MC item of Cat Rescue distinguished language groups in both NA and PWA. Picture-specific MC scores differentially predicted AQ: Cat Rescue in K-PWA and Refused Umbrella in E-PWA. CONCLUSIONS:The findings highlight picture-salient cultural effects in Cat Rescue, even after linguistic adjustments. Limited familiarity with the scene likely hindered Korean speakers' ability to generate core narrative elements. Both linguistic and cultural factors should be considered when selecting picture stimuli for discourse assessment across diverse contexts. SUPPLEMENTAL MATERIAL:https://doi.org/10.23641/asha.31974204.

Objectives: Semantic clustering is a memory strategy that enhances recall performance. The Ratio of Semantic Clustering (RSC) quantifies the use of this strategy, with a decline in RSC indicating episodic memory impairment. This study examines differences in recall accuracy and RSC in young adults, older adults, and individuals with Alzheimer's disease (AD) in immediate (IMM) and delayed (DEL) recall conditions. Methods: Eighty participants (30 young adults, 42 older adults, and 8 individuals with AD) completed the Seoul Verbal Learning Test (SVLT), which consists of IMM and DEL recall tasks. Ancova was conducted to compare the accuracy and RSC across SVLT types (IMM, DEL). Pearson correlation analyses were performed for each group to examine the relationship between accuracy and RSC across recall conditions. Results: Individuals with AD showed lower recall accuracy in delayed recall compared to immediate recall. In contrast, young adults demonstrated increased recall accuracy and RSC in delayed recall, indicating greater use of semantic clustering strategies. Moreover, young adults exhibited strong positive correlations between recall accuracy and RSC across all recall tasks, whereas older adults showed significant correlations only in delayed recall. Conclusion: These findings suggest that strategic memory processes are relatively well-preserved in young adults, whereas the reduced use of semantic clustering in older adults and individuals with AD may indicate cognitive decline.

This study examined the effects of Verb-Semantic Feature Analysis (Verb-SFA) on verb naming, noun retrieval, sentence comprehension, and discourse production in individuals with Dementia of the Alzheimer's Type (DAT). Given the lexical-semantic degradation characteristic of DAT and the central role of verbs in Korean, a verb-final language, this study evaluated whether Verb-SFA facilitates treatment, near-transfer, and far-transfer effects. Three male participants, aged 60 or older with 16 years of education, completed 17 sessions: pre-treatment (4 sessions), treatment (10 sessions), and post-treatment (3 sessions). Treatment effects were assessed using 45-item probe sets derived from the Korean Item Selection Naming Test. Results showed significant improvement in naming accuracy for treated verbs, with a robust interaction between treatment sessions and treated items. No significant near-transfer effects were found for untreated verbs in the probe set or on the Action Naming Test. However, significant near-transfer effects were observed for noun retrieval on the Korean-Boston Naming Test, although verbal fluency tasks showed no improvement. Far-transfer effects emerged in sentence comprehension, suggesting strengthened verb-semantic processing supports higher-level linguistic abilities. No measurable gains were observed in discourse production. Overall, Verb-SFA treatment enhanced verb naming and sentence comprehension in individuals with DAT.

With advancements in Large Language Models, conversational companion robots are increasingly recognized for their potential in supporting and caring for older adults. This study examines older adults’ experiences and functional preferences for a conversational robot designed to enable personalized interactions across multiple sessions. The robot engages users in open-ended conversations by recalling previous dialogues, integrating personal information, and facilitating memory-stimulating conversations. Thirty healthy older adults participated in three one-hour interaction sessions with the robot, followed by post-interaction surveys. Results showed that participants found the interactions engaging and meaningful, expressing high satisfaction with the robot’s ability to remember them and sustain personalized conversations. Among the robot’s functions, health monitoring and retrospective memory support were identified as highly valued by older adults. These findings provide insights for developing more adaptive and socially engaging robots, emphasizing the importance of personalized memory retention and user-tailored interactions in enhancing social support and cognitive engagement for older adults.

Objectives: This study aimed to examine whether lifelong bilingual experience contributes to cognitive reserve in older adults. It focused on differences in working memory and semantic processing abilities between Korean-Japanese bilinguals and Korean monolinguals, considering the influence of typological similarity between the two languages. Methods: Thirty older adults (15 Korean-Japanese bilinguals, 15 Korean monolinguals), all native Korean speakers over 60 years of age, participated in the study. Working memory was assessed using digit span forward and backward tasks. Semantic processing was measured through a semantic relatedness judgment task (SRT), which consisted of word pairs constructed from Sino-Korean words. Stimuli were shown in two formats: Hangul script only, and mixed Hangul-Hanja script. Each pair was either semantically related or unrelated. Participants judged whether the two words were meaningfully related and their accuracy and response times were recorded. Results: Bilingual participants outperformed monolinguals in both working memory tasks. In the SRT, they also showed higher accuracy and faster responses across all conditions. While both groups experienced more difficulty with mixedscript and semantically unrelated pairs, bilinguals consistently demonstrated better performance. Conclusion: The findings suggest that bilingualism involving structurally and lexically similar languages, such as Korean and Japanese, may enhance cognitive reserve and facilitate more efficient language processing in aging. This highlights the cognitive benefits of bilingual experience and its relevance in the context of age-related cognitive decline.

PURPOSE:The current study examined the impact of cross-linguistic and cultural differences on an animal fluency task between Korean- and English-speaking persons with aphasia (PWA) and neurologically intact older adults (OAs). Specifically, we investigated the influence of zodiac animals on word retrieval, given their cultural familiarity in East Asia, hypothesizing that Korean speakers have a higher likelihood of producing zodiac animals compared to English speakers. METHOD:Sixty-seven PWA (30 English-speaking, 37 Korean-speaking) and 30 OAs (15 per language group) completed an animal fluency task. Analyses focused on three approaches: total correct responses, culturally specific responses (zodiac animals and ratio of zodiac animals), and an item-level comparison of language-general and language-specific items to identify animal items that could differentiate between the language groups. RESULTS:Korean speakers, both with and without aphasia, produced a greater proportion of zodiac animals compared to English speakers. Conversely, English speakers demonstrated greater semantic diversity in animal responses than Korean speakers. CONCLUSIONS:Both PWA and OA groups demonstrated differential patterns in producing zodiac animals, depending on their language and the culture. These findings shed light on the importance of considering cultural and linguistic diversity during aphasia assessment of word retrieval difficulties. SUPPLEMENTAL MATERIAL:https://doi.org/10.23641/asha.28942022.

Objectives: Mild Cognitive Impairment (MCI) is a high-risk condition that may progress to Alzheimer's disease, making early screening and clinical intervention essential. Verbal fluency tests are widely used as a simple and effective tool to differentiate MCI from normal aging. This study aimed to compare the performance of three types of verbal fluency tests (semantic, letter and action fluency) between MCI and normal control adults. Finally, we sought to determine which type of verbal fluency test most effectively distinguishes MCI from normal aging. Methods: A total of 52 participants (26 with MCI, 26 controls) participated in this study. Group differences in verbal fluency performance were analyzed, and correlations between verbal fluency and cognitive screening tests were examined. Binary logistic regression analysis was conducted to evaluate the independent discriminative power of verbal fluency. Results: The MCI group exhibited significantly lower performance than the normal controls in the semantic and action fluency tests. Additionally, significant positive correlations were observed between verbal fluency and cognitive function tests in both groups. Among the verbal fluency tests, action fluency was identified as the most sensitive and independent predictor for distinguishing MCI from normal aging. Conclusion: These findings indicate that the action fluency test is a highly sensitive tool for distinguishing MCI from normal aging. The results highlight the potential for the action fluency test to serve as a critical assessment tool in evaluating language and cognitive function in individuals with MCI. This study provides important theoretical and clinical implications for the early detection of MCI and the development of targeted screening methods.

Recent studies have indicated the potential of transcutaneous auricular vagus nerve stimulation (taVNS) as an intervention for cognitive decline. In this study, we systematically analyzed the effects of taVNS on cognitive enhancement from the perspective of brain networks, by combining functional near-infrared spectroscopy (fNIRS) signal analysis with virtual brain simulations. Behavioral experiments with older adults demonstrated that participants with low baseline performance experienced significant improvements in working memory performance following taVNS, while those with high baseline performance tended to decline. This pattern was closely associated with functional connectivity (FC) in the prefrontal cortex (PFC) concurrently measured during the behavioral tasks, i.e., task performance correlated with FC in the PFC, particularly in the medial PFC (mPFC). Moreover, the changes in performance due to taVNS, which varied based on baseline performance, exhibited a notable alignment with the FC changes in the mPFC. These findings were further explored through virtual brain simulations. The simulation results demonstrated that the brain's functional state could vary depending on the network coupling parameter-capable of reflecting loss of structural brain connectivity associated with aging-and that the modulation effects induced by taVNS may also differ based on those functional states. Current results indicate that the efficacy of taVNS interventions for cognitive enhancement may vary according to the pre-intervention structural and functional states of individual brains. Therefore, the development of personalized optimization strategies for taVNS intervention is crucial, and digital brain research holds significant promise in advancing this field.

Age-related hearing loss (ARHL) is associated with an increased risk of dementia, highlighting the need for early interventions to support cognitive functioning. Despite promising evidence supporting transcutaneous auricular vagus nerve stimulation (taVNS) for mitigating cognitive impairment, its impact on working memory (WM) in older adults with ARHL is unexplored. This study is the first attempt to investigate taVNS effects on WM in the older adults with hearing impairment (HI) and with typical hearing (TH). WM capacity was assessed using n-back tasks, varying by WM domains (verbal and visuo-spatial) and complexity levels (1-back and 2-back). Participants underwent a two-session, within-subjects, randomized crossover, single-blind sham-controlled protocol, receiving 20 min of continuous stimulation in the active session, whereas only 30 s at the start and end in the sham session. The HI group performed significantly worse than the TH group on the 2-back tasks. Within the HI group, taVNS significantly enhanced performance across all WM domains and complexity levels compared to the sham condition. These findings suggest that taVNS enhances WM in hearing-impaired older adults, underscoring its potential as a clinical intervention for addressing WM challenges associated with ARHL.