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Action monitoring, the process for evaluating the appropriateness of one's own actions, is reported to be atypical in individuals with autism spectrum disorder (ASD).We examined the characteristics of action monitoring in 11 children with ASD and 12 children with typical development (TD), analyzing stimulus-locked and response-locked event-related potential components (i.e., N2; error-related negativity, ERN; and error positivity, Pe) related to execution of a flanker task.We found a smaller N2 amplitude in children with ASD than in those with TD. Children with ASD also had a larger amplitude of ERN for partial error responses (electromyographic activity corresponding to the inappropriate hand side before response execution) than did children with TD. Additionally, the ERN amplitude for the partial error response was correlated with the Autistic Mannerisms of the Social Responsiveness Scale. There were no significant differences in Pe amplitudes between children with ASD and those with TD.The results suggest that action monitoring in children with ASD is significantly different both before and after response execution. We hypothesized that the detail-focused processing style of ASD reduces the demands of action monitoring before response execution; however, autistic mannerisms evoke excessive concern regarding trivial mistakes after response execution.

Because of unique linguistic characteristics, the prevalence rate of developmental dyslexia is relatively low in the Japanese language. Paradoxically, Japanese children have serious difficulty analysing phonological processes when they have dyslexia. Neurobiological deficits in Japanese dyslexia remain unclear and need to be identified, and may lead to better understanding of the commonality and diversity in the disorder among different linguistic systems. The present study investigated brain activity that underlies deficits in phonological awareness in Japanese dyslexic children using functional magnetic resonance imaging. We developed and conducted a phonological manipulation task to extract phonological processing skills and to minimize the influence of auditory working memory on healthy adults, typically developing children, and dyslexic children. Current experiments revealed that several brain regions participated in manipulating the phonological information including left inferior and middle frontal gyrus, left superior temporal gyrus, and bilateral basal ganglia. Moreover, dyslexic children showed altered activity in two brain regions. They showed hyperactivity in the basal ganglia compared with the two other groups, which reflects inefficient phonological processing. Hypoactivity in the left superior temporal gyrus was also found, suggesting difficulty in composing and processing phonological information. The altered brain activity shares similarity with those of dyslexic children in countries speaking alphabetical languages, but disparity also occurs between these two populations. These are initial findings concerning the neurobiological impairments in dyslexic Japanese children.

Background: Magnocellular deficit theory is among the different hypotheses that have been proposed to explain the pathophysiology of developmental dyslexia (DD). Dysfunction of the magnocellular system in DD has been investigated using mainly visual evoked potentials (VEPs), particularly transient VEPs, although recently abnormal steady-state VEPs have also been reported. The brain regions responsible for the abnormal VEPs in DD have yet to be elucidated, however. In this study, we performed functional magnetic resonance imaging and electroencephalography (fMRI-EEG) simultaneously to elucidate the brain areas that were found in a previous study to be activated through stimulation of the magnocellular system, and then investigated the mechanism involved in the dysfunction seen in DD.Methods: Subjects were 20 healthy individuals (TYP group; 13 men, 7 women; mean ± standard deviation age, 26.3 ± 5.53 years) and 2 men with DD (aged 42 and 30 years). Images of brain activity were acquired with 3-Tesla MRI while the viewing the reversal of low-spatial frequency and low-contrast black-and-white sinusoidal gratings. EEG was recorded concurrently to obtain steady-state VEPs.Results: Stimulus frequency-dependent VEPs were observed in the posterior region of the brain in the TYP group; however, VEP amplitudes in both DD patients were clearly smaller than those in TYP. fMRI images revealed that both the primary and secondary visual cortices were activated by black-and- white sinusoidal gratings in the TYP group, whereas activity in the visual cortex overall was reduced in both DD patients.Conclusions: Present low spatial and high reversal frequency visual stimuli activated the primary visual cortex presumably through predominant activation of the magnocellular pathway. This finding indicates that some cases of adult patients of DD involve impairment of the visual magnocellular system.

Though recent studies have elucidated the earliest mechanisms of processing in multisensory integration, our understanding of how multisensory integration of more sustained and complicated stimuli is implemented in higher-level association cortices is lacking. In this study, we used magnetoencephalography (MEG) to determine how neural oscillations alter local and global connectivity during multisensory integration processing. We acquired MEG data from 15 healthy volunteers performing an audio-visual speech matching task. We selected regions of interest (ROIs) using whole brain time-frequency analyses (power spectrum density and wavelet transform), then applied phase amplitude coupling (PAC) and imaginary coherence measurements to them. We identified prominent delta band power in the temporal pole (TP), and a remarkable PAC between delta band phase and beta band amplitude. Furthermore, imaginary coherence analysis demonstrated that the temporal pole and well-known multisensory areas (e.g., posterior parietal cortex and post-central areas) are coordinated through delta-phase coherence. Thus, our results suggest that modulation of connectivity within the local network, and of that between the local and global network, is important for audio-visual speech integration. In short, these neural oscillatory mechanisms within and between higher-level association cortices provide new insights into the brain mechanism underlying audio-visual integration.

It is assumed that children with autism spectrum disorders (ASD) have specificities for self-face recognition, which is known to be a basic cognitive ability for social development. In the present study, we investigated neurological substrates and potentially influential factors for self-face recognition of ASD patients using near-infrared spectroscopy (NIRS). The subjects were 11 healthy adult men, 13 normally developing boys, and 10 boys with ASD. Their hemodynamic activities in the frontal area and their scanning strategies (eye-movement) were examined during self-face recognition. Other factors such as ASD severities and self-consciousness were also evaluated by parents and patients, respectively. Oxygenated hemoglobin levels were higher in the regions corresponding to the right inferior frontal gyrus than in those corresponding to the left inferior frontal gyrus. In two groups of children these activities reflected ASD severities, such that the more serious ASD characteristics corresponded with lower activity levels. Moreover, higher levels of public self-consciousness intensified the activities, which were not influenced by the scanning strategies. These findings suggest that dysfunction in the right inferior frontal gyrus areas responsible for self-face recognition is one of the crucial neural substrates underlying ASD characteristics, which could potentially be used to evaluate psychological aspects such as public self-consciousness.

Phonological awareness is essential for reading, and is common to all language systems, including alphabetic languages and Japanese. This cognitive factor develops during childhood, and is thought to be associated with shifts in brain activity. However, the nature of this neurobiological developmental shift is unclear for speakers of Japanese, which is not an alphabetical language. The present study aimed to reveal a shift in brain functions for processing phonological information in native-born Japanese children. We conducted a phonological awareness task and examined hemodynamic activity in 103 children aged 7 to 12 years. While younger children made mistakes and needed more time to sort phonological information in reverse order, older children completed the task quickly and accurately. Additionally, younger children exhibited increased activity in the bilateral dorsolateral prefrontal cortex, which may be evidence of immature phonological processing skills. Older children exhibited dominant activity in the left compared with the right dorsolateral prefrontal cortex, suggesting that they had already acquired phonological processing skills. We also found significant effects of age and lateralized activity on behavioral performance. During earlier stages of development, the degree of left lateralization appears to have a smaller effect on behavioral performance. Conversely, in later stages of development, the degree of left lateralization appears to have a stronger influence on behavioral performance. These initial findings regarding a neurobiological developmental shift in Japanese speakers suggest that common brain regions play a critical role in the development of phonological processing skills among different languages systems, such as Japanese and alphabetical languages.

Developmental dyslexia (DD) is a neurodevelopmental disorder that is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. The magnocellular deficit theory is one of several hypotheses that have been proposed to explain the pathophysiology of DD. In this study, we investigated magnocellular system dysfunction in Japanese dyslexic children.Subjects were 19 dyslexic children (DD group) and 19 aged-matched healthy children (TD group). They were aged between 7 and 16 years. Reversed patterns of black and white sinusoidal gratings generated at a low spatial frequency, high reversal frequency of 7.5 Hz, and low contrasts were used specifically to stimulate the magnocellular system. We recorded visual evoked potentials (VEP) from the occipital area and examined their relationship with reading and naming tasks, such as the time to read hiragana characters, rapid automatized naming of pictured objects, and phonological manipulation.Compared to the TD group, the DD group showed a significantly lower peak amplitude of VEPs through the complex demodulation method. Structural equation modeling showed that VEP peak amplitudes were related to the rapid automatized naming of pictured objects, and better rapid automatized naming resulted in higher reading skills. There was no correlation between VEP findings and the capacity for phonological manipulation.VEPs in response to the magnocellular system are useful for understanding the pathophysiology of DD. Single phonological deficit may not be sufficient to cause DD.

Helical magnetic structures and its responses to external magnetic fields in Yb(Ni$_x$Cu$_{1-x}$)$_3$Al$_9$, with a chiral crystal structure of the space group $R32$, have been investigated by resonant X-ray diffraction. It is shown that the crystal chirality is reflected to the helicity of the magnetic structure by a one to one relationship, indicating that there exists an antisymmetric exchange interaction mediated via the conduction electrons. When a magnetic field is applied perpendicular to the helical axis ($c$ axis), the second harmonic peak of $(0, 0, 2q)$ develops with increasing the field. The third harmonic peak of $(0, 0, 3q)$ has also been observed for the $x$=0.06 sample. This result provides a strong evidence for the formation of a chiral magnetic soliton lattice state, a periodic array of the chiral twist of spins, which has been suggested by the characteristic magnetization curve. The helical ordering of magnetic octupole moments, accompanying with the magnetic dipole order, has also been detected., Comment: 13 pages, 18 figures, accepted for publication in J. Phys. Soc. Jpn

Background : Psychometric properties of The Japanese version of Swanson, Nolan, and Pelham IV scale (SNAP-IV)-Teacher Form were examined in this study. Method : Community samples of 1296 children (Grade 1–9, boys 52.9%) were collected from public elementary/middle schools in suburban areas. Teachers rated their children’s behavior using Japanese version of SNAP-IV-Teacher Form and Strength and Difficulties Questionnaire (SDQ). Results : A three-factor structure model, which was equivalent with AD/HD symptoms subscales (inattention, hyperactivity/impulsivity) and oppositional-defiant disorder symptoms subscale was obtained and confirmed in an explorative/confirmative factorial analysis (Goodness-of-Fit Index = 0.913, Comparative Fit Index = 0.959, root mean square error of approximation = 0.056). The current version of the SNAP-IV-Teacher Form demonstrated good test–retest reliability (intra-class correlation = 0.752–0.822), high internal consistency (Cronbach’s α = 0.933–0.952), significant correlations with relevant subscales of Japanese version of SDQ, and typical effects of age and gender on those subscales. Conclusion : The current study indicates that the Japanese version of SNAP-IV-Teacher Form is a reliable and valid instrument for rating symptoms related to AD/HD and ODD.

This study examined the effects of a rich, emotionally-satisfying childbirth experience (CBE) of mothers on the behavior of school-age children using longitudinal data measured from immediately to 7 years and 6 months after birth. The results of structural equation modeling revealed the following: 1) giving birth in a midwifery center enhances emotional satisfaction with CBE, 2) a rich CBE of mothers was associated with parental warmth, 3) parental warmth during early childhood increased prosocial behavior and reduced behavioral problems in school-age children, and 4) temperamentally difficulty in early childhood were linked to later behavioral problems in school-age children. Thus, a rich CBE and parental warmth were suggested to be factors contributing to the good behavior of school-age children.

The current study sought to develop a new behavioral analysis methods to evaluate the effects of social skills training (SST). SST is known to be an effective method to improve the social skills of children with behavioral problems. However, current evaluation methods involve behavioral rating scales that are heavily dependent on evaluators' particular experiences they have had. To quantitatively examine the behavioral effects of SST, we examined subjects' head-movements related to social behavior, using a two-dimensional motion capture system (Kissei Comtec, Japan). Four children (three male, one female, 7-8 years of age) with pervasive developmental disorder (PDD) or attention deficit/hyperactivity disorder (AD/HD) participated in 16 sessions of SST. Before and after SST, head-coordinates on a two-dimensional plane were calculated using their behavior during a pair task, measured by four digital cameras. After SST, the number of communication behaviors was increased compared to before SST. In addition, children looked longer at another child within 30 degrees of the central visual field. Time-series analysis of the visual field during the detection of another child revealed significant auto-correlation from about -1.12 second. before to the beginning of communication behavior (p0.05). The results suggested that our method can provide a quantitative index of characteristics related to skilled social behaviors. We conclude that a two-dimensional motion capture system would be useful for visualization of the interventional effects of SST, which would supplement assessments by the conventional observational strategies.

The present study aimed to review previous research conducted on face recognition in patients with autism spectrum disorders (ASD). Face recognition is a key question in the ASD research field because it can provide clues for elucidating the neural substrates responsible for the social impairment of these patients. Historically, behavioral studies have reported low performance and/or unique strategies of face recognition among ASD patients. However, the performance and strategy of ASD patients is comparable to those of the control group, depending on the experimental situation or developmental stage, suggesting that face recognition of ASD patients is not entirely impaired. Recent brain function studies, including event-related potential and functional magnetic resonance imaging studies, have investigated the cognitive process of face recognition in ASD patients, and revealed impaired function in the brain's neural network comprising the fusiform gyrus and amygdala. This impaired function is potentially involved in the diminished preference for faces, and in the atypical development of face recognition, eliciting symptoms of unstable behavioral characteristics in these patients. Additionally, face recognition in ASD patients is examined from a different perspective, namely self-face recognition, and facial emotion recognition. While the former topic is intimately linked to basic social abilities such as self-other discrimination, the latter is closely associated with mentalizing. Further research on face recognition in ASD patients should investigate the connection between behavioral and neurological specifics in these patients, by considering developmental changes and the spectrum clinical condition of ASD.

To reveal the neural substrate of communication difficulties in children with autism spectrum disorders (ASDs), we investigated the P300 component of event-related potentials (ERPs) as represented by the average of electroencephalography findings time-locked to events and behavior. Because the P300 amplitude influences attentional resource allocation during discrimination, the component elicited during perception of known and unknown faces should indicate familiarity processing.Nine typically developing children (TD) and nine children with ASDs participated in this study (Experiment 1). The P300 amplitude in TD children was significantly larger during familiar face perception than during unfamiliar face perception (p0.01). However, there was no evidence of familiarity effect in children with ASDs. In three children with ASDs, we also assessed the P300 amplitude during perception of a therapist's face one month before (baseline), a few days before and after social skills training (SST) sessions (Experiment 2). To evaluate the effect of familiarity on facial identity processing, we analyzed the therapist/unknown ratio of P300 amplitudes related to the face discrimination task as an index. The ratio was larger after SST sessions than before, but there was no difference in the ratio between baseline and before SST assessments.The P300 might be influenced by attentional resource allocation depending on the stage of learning face identification in children with ASDs. We speculate that this approach to evaluating brain responses during facial identity recognition could be used as a tool to clarify children's communication difficulties.

Two hundred and seven Japanese elementary school children aged from 6 (Grade 1) to 12 (Grade 6) years old were tested for their abilities to name numbers and pictured objects along with reading Hiragana characters and words. These children all showed typical development and their classroom teachers judged that they were not having any problems with reading or writing. The children were randomly divided into two groups, the first group was assigned to two naming tasks;the rapid automatized naming (RAN) of "numbers" and "pictured objects," the second group was assigned to two rapid alternative stimulus (RAS) naming tasks using numbers and pictured objects. All children were asked to perform two reading tasks that were written in Hiragana script: single mora reading task and four syllable word reading task. The total articulation time for naming and reading and performance in terms of accuracy were measured for each task. Developmental changes in these variables were evaluated. The articulation time was significantly longer for the first graders, and it gradually shortened as they moved through to the upper grades in all tasks. The articulation time reached a plateau in the 5th grade for the number naming, while gradual change continued after drastic change in the lower grades for the pictured object naming. The articulation times for the single mora reading and RAN of numbers correlated strongly. The articulation time for the RAS naming was significantly longer compared to that for the RAN, though there were very few errors. The RAS naming showed the highest correlation with the four syllable word reading. This study demonstrated that the performance in rapid automatized naming of numbers and pictures were closely related with performance on reading tasks. Thus Japanese children with reading disorders such as developmental dyslexia should also be evaluated for rapid automatized naming.

We investigated the clinical symptoms of children with developmental dyslexia (DD) and evaluated the relationship between these symptoms and their Hiragana reading abilities. In order to detect the clinical symptoms of DD, we newly developed a clinical-symptoms-checklist (CL), which consisted of a total of 30 yes/no questions regarding symptoms linked to reading (15 questions) and writing (15 questions). Subjects were 98 Japanese school grade (1 to 9) children, aged 6 to 15 years old, with normal intelligence confirmed by the Wechsler Intelligence Test for Children (WISC-Ill) and they were divided into 2 groups according to their diagnosis. Twenty four children diagnosed as developmental dyslexia consisted the DD group, and the remaining 74 children were grouped in the non-DD group. CL showed significant construct validity (p0.05) and inner consistency (reading: a =0.82, writing: a =0.72) after deleting two questions from the originals. The number of questions checked in the CL reading subcategory significantly correlated with the Hiragana reading ability of articulation time in all Hiragana reading tasks (p0.001). More severe clinical symptoms and lower reading ability were observed in the DD group compared to the non-DD group. Receiver Operating Characteristics (ROC) analysis indicated that these two groups could be discriminated by the CL and the results of the reading task, and both sensitivity and specificity rate were approximately 80%. It was suggested that 7 or more positive checks in the CL and 2 or more abnormal scores in the reading tasks might discriminate DD from other conditions which cause difficulties in reading and writing in Japanese children.

BACKGROUND: During face identification in humans, facial information is sampled (seeing) and handled (processing) in ways that are influenced by the kind of facial image type, such as a self-image or an image of another face. However, the relationship between seeing and information processing is seldom considered. In this study, we aimed to reveal this relationship using simultaneous eye-tracking measurements and near-infrared spectroscopy (NIRS) in face identification tasks. METHODOLOGY/PRINCIPAL FINDINGS: 22 healthy adult subjects (8 males and 14 females) were shown facial morphing movies in which an initial facial image gradually changed into another facial image (that is, the subject's own face was changed to a familiar face). The fixation patterns on facial features were recorded, along with changes in oxyhemoglobin (oxyHb) levels in the frontal lobe, while the subjects identified several faces. In the self-face condition (self-face as the initial image), hemodynamic activity around the right inferior frontal gyrus (IFG) was significantly greater than in the familiar-face condition. On the other hand, the scanning strategy was similar in almost all conditions with more fixations on the eyes and nose than on other areas. Fixation time on the eye area did not correlate with changes in oxyHb levels, and none of the scanning strategy indices could estimate the hemodynamic changes. CONCLUSIONS/SIGNIFICANCE: We conclude that hemodynamic activity, i.e., the means of processing facial information, is not always modulated by the face-scanning strategy, i.e., the way of seeing, and that the right IFG plays important roles in both self-other facial discrimination and self-evaluation.

In order to clarify the origin of the graded magnetic properties by the substrate rotational speed for electroless CoNiP films, electrochemical characteristics such as mixed potential and polarization behaviors were investigated. The results of mixed potential analysis revealed that the cathodic and anodic partial reactions in this system were diffusion‐ and reaction‐controlled state, respectively. It was shown that the mixed potential of the CoNiP deposition with the substrate rotational speed was dominated mainly by the deposition reaction of Co. The results of the polarization curves for each metal ion clarified that the Co deposition is in the diffusion‐controlled state, whereas such a tendency did not appear for the deposition of Ni. This suggests that such a difference in deposition behaviors between Co and Ni with respect to the rotational speed of the substrate results in the formation of graded film properties. © 2000 The Electrochemical Society. All rights reserved.

Gradient control of magnetic properties in electroless-deposited CoNiP films was attempted and microstructural origin of the graded properties was investigated. Control of the single and dual gradient in magnetic properties, such as coercivity, Hc, in the direction of the film thickness was achieved by controlling the rotational speed of substrates during the deposition. The results of cross-sectional scanning electron microscopy and transmission electron microscopy investigations clarified that the size of the crystallites changed according to the speed of the rotation, forming the graded microstructure in the film thickness direction, which resulted in the graded properties.