Atypical brain lateralization for speech processing at the sublexical level in autistic children revealed by fNIRS.

Autistic children often exhibit atypical brain lateralization of language processing, but it is unclear what aspects of language contribute to this phenomenon. This study employed functional near-infrared spectroscopy to measure hemispheric lateralization by estimating hemodynamic responses associated with processing linguistic and non-linguistic auditory stimuli. The study involved a group of autistic children (N = 20, mean age = 5.8 years) and a comparison group of nonautistic peers (N = 20, mean age = 6.5 years). The children were presented with stimuli with systematically decreasing linguistic relevance: naturalistic native speech, meaningless native speech with scrambled word order, nonnative speech, and music. The results revealed that both groups showed left lateralization in the temporal lobe when listening to naturalistic native speech. However, the distinction emerged between autism and nonautistic in terms of processing the linguistic hierarchy. Specifically, the nonautistic comparison group demonstrated a systematic reduction in left lateralization as linguistic relevance decreased. In contrast, the autism group displayed no such pattern and showed no lateralization when listening to scrambled native speech accompanied by enhanced response in the right hemisphere. These results provide evidence of atypical neural specialization for spoken language in preschool- and school-age autistic children and shed new light on the underlying linguistic correlates contributing to such atypicality at the sublexical level.

Absence of associations with prefrontal cortex and cerebellum may link to early language and social deficits in preschool children with ASD.

Introduction: Autism spectrum disorder (ASD) is a complex developmental disorder, characterized by language and social deficits that begin to appear in the first years of life. Research in preschool children with ASD has consistently reported increased global brain volume and abnormal cortical patterns, and the brain structure abnormalities have also been found to be clinically and behaviorally relevant. However, little is known regarding the associations between brain structure abnormalities and early language and social deficits in preschool children with ASD. Methods: In this study, we collected magnetic resonance imaging (MRI) data from a cohort of Chinese preschool children with and without ASD (24 ASD/20 non-ASD) aged 12-52 months, explored group differences in brain gray matter (GM) volume, and examined associations between regional GM volume and early language and social abilities in these two groups, separately. Results: We observed significantly greater global GM volume in children with ASD as compared to those without ASD, but there were no regional GM volume differences between these two groups. For children without ASD, GM volume in bilateral prefrontal cortex and cerebellum was significantly correlated with language scores; GM volume in bilateral prefrontal cortex was significantly correlated with social scores. No significant correlations were found in children with ASD. Discussion: Our data demonstrate correlations of regional GM volume with early language and social abilities in preschool children without ASD, and the absence of these associations appear to underlie language and social deficits in children with ASD. These findings provide novel evidence for the neuroanatomical basis associated with language and social abilities in preschool children with and without ASD, which promotes a better understanding of early deficits in language and social functions in ASD.

Effectiveness of cloud-based rehabilitation in children with developmental language disorder during the COVID-19 pandemic: A prospective cohort study.

During the coronavirus disease 2019 pandemic, we considered the case of a child with developmental language disorder (DLD) who could not go to the hospital on time to receive timely rehabilitation treatment due to disrupted hospital operations. The application of cloud-based rehabilitation platforms has provided significant advantages and convenience for children with DLD in-home remote rehabilitation. Among them, the JingYun Rehab Cloud Platform is the most widely used in mainland China. It is an interactive telerehabilitation system developed by Weixin Huang that delivers personalized home rehabilitation for special education children. In this study, we used the JingYun Rehab Cloud Platform to investigate the extent to which cloud-based rehabilitation is effective for children with DLD in terms of language and cognitive outcomes. This was a prospective cohort study including all children who were evaluated and diagnosed with DLD through Sign-Significant Relations and were followed up at the rehabilitation clinic of our institute. We followed 162 children with DLD for 3 months, including 84 children with DLD who participated in remote cloud-based rehabilitation on the JingYun Rehab Cloud Platform and 78 children with DLD as the control group who underwent home-based rehabilitation. Language abilities of both groups were assessed using the Chinese version of the Peabody Picture Vocabulary Test-Revised. Several measures of training performance (language, memory, and cognition tasks) were assessed before and after cloud-based rehabilitation in the remote cloud-based rehabilitation group. Children with DLD in the cloud-based rehabilitation group performed significantly better in language abilities, as assessed by the Peabody Picture Vocabulary Test-Revised, than children with DLD in the control group. Furthermore, for children who participated in remote cloud-based rehabilitation, the frequency of training sessions was proportional to their performance on language, memory, and cognition tasks. This study demonstrated the effectiveness of cloud-based rehabilitation on the JingYun Rehab Cloud Platform in treating children with DLD.

Perception of the /t/-/k/ contrast by Mandarin-speaking children with Speech Sound Disorders.

Mandarin-speaking children with speech sound disorders (SSD) often show difficulties in producing alveolar and velar plosives contrasts (e.g., /t/ vs. /k/). But it remains unclear whether such phonological disorder correlates with the perception of the contrast between alveolar and velar plosives. The present study assessed whether Mandarin-speaking children with SSD who substituted [t] for /k/ in production could perceptually distinguish between /t/ and /k/, and compared their results with those from typically developing children (TDC) and typically adults (TA). We adopted a categorical perception paradigm with a /ta/-/ka/ continuum. The continuum included nine stimuli, which were synthesized from a naturally-produced /ta/. The SSD, TDC, and TA groups completed both identification and discrimination tasks that required perceptual judgment of individual stimulus and pairs of stimuli from the continuum. The results showed that the TDC and TA groups showed typical patterns of categorical perception in the continuum. But the SSD group only reached or was slightly above the chance level in the identification task and did not show significant difference among pairs of stimuli in the discrimination task. Their performance was significantly different from that of the TDC and TA groups and lacked typical patterns of categorical perception. The results suggested that their perception of /t/ vs. /k/ may be impaired. Considering the SSD group's speech errors, this perception defect may be a cause for their tendency of substituting [t] for /k/ in production.

microRNA-665 is down-regulated in gastric cancer and inhibits proliferation, invasion, and EMT by targeting PPP2R2A.

Recently, microRNA-665 (miR-665) has been reported to function as both tumour suppressor and oncogene in several cancer types, including gastric cancer, hepatocellular cancer, and lung cancer. However, the biological function of miR-665 and its precise mechanisms in gastric cancer (GC) have not been well clarified. The aim of this study was to study the roles of miR-665/PPP2R2A axis in GC. The levels of PPP2R2A and miR-665 were detected by quantitative PCR assay in GC tissues and cell lines. Moreover, the biological roles of miR-665 and PPP2R2A in GC cells were assessed by cell proliferation, invasion, and epithelial-mesenchymal transition (EMT). The mRNA and protein levels of PPP2R2A were determined by using quantitative PCR and Western blotting assays. Luciferase assays were used to confirm that PPP2R2A was one target of miR-665. In this study, the miR-665 level was dramatically reduced in GC tissues and cell lines, and the PPP2R2A expression was significantly enhanced. What is more, the PPP2R2A expression was negatively related to the miR-665 level in GC tissues. Furthermore, up-regulation of miR-665 obviously restrained GC cells proliferation, invasion, and EMT. We confirmed that miR-665 could directly target PPP2R2A by luciferase reporter assay. Besides, knockdown of PPP2R2A also could markedly inhibit the proliferation, invasion and EMT of GC cells. Finally, overexpression of miR-665 in GC cells partially reversed the promoted effects of PPP2R2A up-regulation. Overexpression of miR-665 restrained GC cells proliferation, invasion and EMT via regulation of PPP2R2A. SIGNIFICANCE OF THE STUDY: miR-665 has been reported to function as oncogene or tumour suppressor in different cancers. However, the precise roles of miR-665 in GC have not been elucidated. Our study for the first time demonstrated that miR-665 level was significantly down-regulated in GC. Additionally, miR-665 overexpression inhibited cell growth, invasion, and EMT of GC. Moreover, our data suggested a significant negative correlation between miR-665 and PPP2R2A expression in GC. MiR-665 suppressed GC cell proliferation, invasion, and EMT by directly targeting PPP2R2A, which suggested important roles for miR-665/PPP2R2A axis in the GC pathogenesis and its potential application in cancer therapy.

Electrophysiological evidence of language switching for bidialectals: an event-related potential study.

Language switching is an important issue in the study of bilinguals. However, how the nontarget language affects the production of the target language under the language switch condition is still unclear, especially for bilinguals who speak two dialects (bidialectals). In the present study, we investigate this issue by a picture-naming task and using an event-related potential (ERP) technique. Two groups of proficient bidialectals, Mandarin (L1)-Cantonese (L2) and Cantonese (L1)-Mandarin (L2), participated in the study. They were required to name pictures with Mandarin or Cantonese under language switching conditions and language nonswitching conditions. The results showed that participants of both groups showed significant longer reaction time, larger P200, and smaller N400 under language switching conditions than that under language nonswitching conditions, which reflects the language switching costs. Moreover, participants of the two groups showed different P200 and N400 between Mandarin-Cantonese (MC) switching conditions and Cantonese-Mandarin (CM) switching conditions. Specifically, MC bidialectals showed larger P200 under the CM condition than that under the MC condition, whereas CM bidialectals showed an opposite P200 pattern (CM conditionCM condition). These findings supported the language-unspecific selection theory. Overall, our study is the first to provide electrophysiological evidence of language switching between two dialects.

Repetition Priming Effects in Proficient Mandarin-Cantonese and Cantonese-Mandarin Bidialectals: An Event-Related Potential Study.

The present study adopted a repetition priming paradigm to investigate the bidialectal (bilingual) representation of speakers with different native dialects by event-related potential (ERP) technique. Proficient Mandarin-Cantonese and Cantonese-Mandarin bidialectals participated in the study. They were required to judge whether a word was a biological word or not, when the words (target word) were represented under four types of repetition priming conditions: Mandarin (prime)-Mandarin (target), Mandarin (prime)-Cantonese (target), Cantonese (prime)-Cantonese (target) and Cantonese (prime)-Mandarin (target). Results of reaction time and accuracy primarily indicated larger repetition priming effects in Mandarin-Mandarin and Cantonese-Cantonese (within-language) conditions than that in Mandarin-Cantonese and Cantonese-Mandarin (between-language) conditions. But more importantly, P200 and N400 mean amplitudes revealed distinct repetition priming effects between two types of participants. Specifically, both P200 and N400 indicated that the repetition priming effect in Mandarin-Mandarin condition was larger than that in Cantonese-Cantonese condition for Mandarin-Cantonese participants, whereas it was opposite for Cantonese-Mandarin participants. In addition, P200 also suggested opposite patterns of repetition priming effects in between-language priming conditions for two groups of participants. The repetition priming effect in Mandarin-Cantonese condition was larger than that in Cantonese-Mandarin condition for Mandarin-Cantonese participants, while for Cantonese-Mandarin participants, it was opposite (Mandarin-Cantonese < Cantonese-Mandarin). The results implied a clear asymmetric representation of two dialects for proficient bidialectals. They were further discussed in light of native dialect and language use frequency.