Ming-Tao Yang

The Development of Mismatch Responses to Mandarin Lexical Tones in Early Infancy

This study examined how maturation and the size of deviance affect the development of mismatch responses to Mandarin lexical tones by a multi-deviant oddball paradigm with both large deviant T1/T3 and small deviant T2/T3 pairs in newborns and 6-month-olds. The T1/T3 pair elicited a positive mismatch response (P-MMR) at birth but an adult-like mismatch negativity (MMN) at 6 months of age. For the T2/T3 pair, no significant MMR was seen in newborns, whereas a P-MMR was found when infants are 6 months old. Results suggest that the developmental trajectories of MMRs are dependent on the neural maturation and the discriminability of tonal changes.

Hyperactivity and Impulsivity in Children with Untreated Allergic Rhinitis: Corroborated by Rating Scale and Continuous Performance Test

BACKGROUND Allergic rhinitis (AR) is the most common chronic allergic disease in school-age children. An increased prevalence of attention deficit hyperactivity disorder (ADHD) in AR patients has been reported; however, inattention and hyperactivity in AR children have not been investigated using objective and scientific measurements. METHODS We used AR symptom score, ADHD symptom scale, and computerized continuous performance test (CPT) to study the attention and impulsivity in AR children, age-matched controls, and ADHD children (aged 6-15 years). Univariate and multivariate linear regression analyses were applied to identify risk factors for impulsivity and inattention in AR children. RESULTS Twenty-nine controls, 10 ADHD, and 105 AR children were enrolled. There were no differences in age and sex among the three groups. The scores of Hyperactivity/Impulsivity subscales of ADHD symptoms from both parents and teachers were significantly higher in the AR children. The CPT in AR children revealed higher commission errors, shorter reaction times, and more perseveration. Risk factors for inattention and impulsivity in AR children included younger age, male sex, higher AR symptom scores, persistent AR, moderate/severe AR, multiple atopic diseases, family history of atopy, and possible comorbidity with ADHD. CONCLUSION Care for AR children should not only involve treating their allergy, but also monitoring the possible comorbidities of impulsivity and inattention. In children with impulsivity, AR should be considered in addition to ADHD.

Targeted Delivery of Erythropoietin by Transcranial Focused Ultrasound for Neuroprotection against Ischemia/Reperfusion-Induced Neuronal Injury: A Long-Term and Short-Term Study

Erythropoietin (EPO) is a neuroprotective agent against cerebral ischemia/reperfusion (I/R)-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS) sonication with microbubbles (MBs) can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO) for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg) with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS) was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection.

Feature-specific transition from positive mismatch response to mismatch negativity in early infancy: Mismatch responses to vowels and initial consonants

This study investigated how phonological saliency, deviance size, and maturation affect mismatch responses (MMRs) in early infancy. MMRs to Mandarin vowels and initial consonants were measured using a multi-deviant oddball paradigm in adults, newborns, and 6-month-olds. The vowel condition consisted of Mandarin syllable da as the standard, du as the large deviant and di as small deviant. As for initial consonant condition, we took syllable ba as standard, ga as large deviant, and ba as small deviant. While adults showed typical mismatch negativities (MMNs), newborns demonstrated broad positive MMRs (P-MMRs) to both initial consonants and vowels. For 6-month-olds, deviance size affected the polarity of MMRs to vowels. The large deviant du/da contrast elicited an adult-like MMN, while the small deviant di/da contrast elicited a P-MMR. Initial consonant changes elicited only P-MMRs, regardless of deviance size. In summary, MMRs to vowels switched from P-MMR at birth to MMN at 6 months. However, the polarity transition was not found for MMRs to initial consonants. The developmental trajectories of MMRs to vowels and initial consonants further support the phonological saliency hypothesis.

Attention deficits revealed by passive auditory change detection for pure tones and lexical tones in ADHD children

Inattention (IA) has been a major problem in children with attention deficit/hyperactivity disorder (ADHD), accounting for their behavioral and cognitive dysfunctions. However, there are at least three processing steps underlying attentional control for auditory change detection, namely pre-attentive change detection, involuntary attention orienting, and attention reorienting for further evaluation. This study aimed to examine whether children with ADHD would show deficits in any of these subcomponents by using mismatch negativity (MMN), P3a, and late discriminative negativity (LDN) as event-related potential (ERP) markers, under the passive auditory oddball paradigm. Two types of stimuli—pure tones and Mandarin lexical tones—were used to examine if the deficits were general across linguistic and non-linguistic domains. Participants included 15 native Mandarin-speaking children with ADHD and 16 age-matched controls (across groups, age ranged between 6 and 15 years). Two passive auditory oddball paradigms (lexical tones and pure tones) were applied. The pure tone oddball paradigm included a standard stimulus (1000 Hz, 80%) and two deviant stimuli (1015 and 1090 Hz, 10% each). The Mandarin lexical tone oddball paradigm’s standard stimulus was /yi3/ (80%) and two deviant stimuli were /yi1/ and /yi2/ (10% each). The results showed no MMN difference, but did show attenuated P3a and enhanced LDN to the large deviants for both pure and lexical tone changes in the ADHD group. Correlation analysis showed that children with higher ADHD tendency, as indexed by parents’ and teachers’ ratings on ADHD symptoms, showed less positive P3a amplitudes when responding to large lexical tone deviants. Thus, children with ADHD showed impaired auditory change detection for both pure tones and lexical tones in both involuntary attention switching, and attention reorienting for further evaluation. These ERP markers may therefore be used for the evaluation of anti-ADHD drugs that aim to alleviate these dysfunctions.

Attention-deficit/hyperactivity disorder-related symptoms improved with allergic rhinitis treatment in children.

Background Increased prevalence of attention-deficit/hyperactivity disorder (ADHD) in children with allergic rhinitis (AR) has been reported. Our previous study showed that children with untreated AR had higher ADHD scores than did the controls. Objective This prospective follow-up study aimed to investigate whether elevated ADHD scores in children with AR could be decreased by AR treatment. Methods Sixty-eight children with AR (age range, 6-14 years) and who were drug naive were enrolled and evaluated by AR symptom score, ADHD symptom scores, and computerized continuous performance test, before and after AR therapy, which included nonpharmacologic intervention, oral antihistamines, and topical steroids. Thirty-one age-matched controls and 13 children with pure ADHD were also enrolled for comparison. The relationship between the AR and ADHD score change was analyzed by a partial correlation test, and univariate and multivariate linear regression models were applied to investigate possible predictors for the improvement of ADHD scores by AR treatment. Results AR symptom scores in children with AR decreased significantly after treatment (p < 0.001), and their ADHD scores also decreased significantly (p < 0.001). An improved AR symptom score was positively correlated with improved detectability (rp = 0.617, p = 0.001) and commission error (rp = 0.511, p = 0.011). Significant predictors for the improvement of ADHD scores included age, AR drugs, AR subtypes, and multiple atopic diseases (ps < 0.05). Conclusion Higher ADHD scores in children with AR compared with healthy controls decreased significantly with AR treatment. For children with AR and borderline ADHD symptoms, who do not meet full ADHD diagnostic criteria, we recommend initially treating their AR and monitoring improvement of ADHD symptoms.

The therapeutic implication of a novel SCN2A mutation associated early-onset epileptic encephalopathy with Rett-like features

Epileptic encephalopathies are highly heterogeneous and phenotypical disorders with different underlying genetic defects. Mutations in the SCN2A gene cause different epilepsy syndromes, including epilepsy of infancy with migrating focal seizures, Ohtahara syndrome, and West syndrome. We utilized a targeted next generation sequencing (NGS) approach on a girl with early-onset seizures and Rett-like features, including autistic behavior, limited hand function with chorea, and profound intellectual disability, to identify novel missense mutation (c.1270G>A; p.V424M) in the SCN2A gene, which encodes the αII-subunit of the voltage-gated Na+ channel (Nav1.2). The identified SCN2A mutation responsible for the development of the disease is confirmed to be de novo for the proband. Our findings broaden the clinical spectrum of SCN2A mutations, which resembles clinical phenotypes of SCN1A mutations by manifesting as fever sensitive seizures, and highlights that SCN2A mutations are an important cause of early-onset epileptic encephalopathies with movement disorders. In addition, the use of levetiracetam to treat SCN2A epileptic encephalopathy, when Na+ channel-blocking anticonvulsants are ineffective, is also recommended.

Schwartz-Jampel syndrome: Report of one case

We report a case of Schwartz-Jampel syndrome in a 2-year-9-month-old Taiwanese girl and her clinical response to treatment. She had a history of generalized muscle stiffness and hypertrophy since birth. Clinical and electromyographic myotonia were noted. Other clinical features included short stature, unusual facial appearance, ophthalmoplegia, elbow joint contractures, and developmental hip dysplasia. Muscle stiffness and myotonia improved after infusion of lidocaine. She then received oral mexiletine and the symptoms significantly improved.