Why is it difficult for children and adults to follow a person's eye gaze in polynomial social relationships with compound audio-visual stimuli: An eye-tracking study.

Acquiring triadic social interactions could facilitate language and communication skills in early infancy. However, studies have rarely investigated polynomial relationships, defined as relationships among the self, two or more people, and objects. During the development from a child to an adult, the responsiveness to a preferred stimulus modality changes from visual to auditory dominance. Nevertheless, how people observe compound visual stimuli in polynomial social relationships and why it is difficult to ignore auditory cues remain unclear. Moreover, there is a need to identify differences between children's and adults' observing latencies in the time to the first fixation when detecting a stimulus. This study examined whether participants (24 adults and 19 children) demonstrated similar gaze patterns under triadic and polyadic conditions. The participants observed a target visual stimulus looked at by a face stimulus while we presented spoken names, either congruent or incongruent with the target visual stimulus. The results indicated that when the number of people in social relationships increased, children and adults decreased fixations on the target face and the stimulus and showed a shorter mean fixation duration on the face. Moreover, children had longer latencies and more fixation errors for the target stimulus, which might reflect children's difficulties in communicating with others. We expect that understanding children's communication transition from triadic to polynomial social relationships with audio-visual stimulus congruencies would facilitate understanding language development and social communication patterns.

Segment-Unit Reading Comprehension Training for Japanese Students with Autism Spectrum Disorder and Learning Disabilities.

Students with autism spectrum disorder (ASD) and learning disabilities (LDs) often experience reading difficulties. In particular, reading long passages can cause comprehension problems. We examined whether 8 Japanese students with ASD, 7 students with LDs, and 13 typically developing (TD) students improved their reading comprehension through two types of repeated reading training: whole-sentence-unit reading (WSUR) training and segment-unit reading (SUR) training. Participants undergoing WSUR training read whole sentences repeatedly. In SUR training, they repeatedly read a segment of a sentence in its correct spatial location. Results indicated that students with ASD and LDs showed greater improvement in reading comprehension after SUR training than after WSUR training, whereas both procedures were equally effective for TD students. Moreover, students with ASD showed only negligible reading comprehension improvements, whereas students with LDs showed intermediate improvements after WSUR training. These results suggest that sequentially presenting word segments can improve the reading comprehension of students with ASD and specific LDs.

Applied Machine Learning Method to Predict Children With ADHD Using Prefrontal Cortex Activity: A Multicenter Study in Japan.

Objective: To establish valid, objective biomarkers for ADHD using machine learning. Method: Machine learning was used to predict disorder severity from new brain function data, using a support vector machine (SVM). A multicenter approach was used to collect data for machine learning training, including behavioral and physiological indicators, age, and reverse Stroop task (RST) data from 108 children with ADHD and 108 typically developing (TD) children. Near-infrared spectroscopy (NIRS) was used to quantify change in prefrontal cortex oxygenated hemoglobin during RST. Verification data were from 62 children with ADHD and 37 TD children from six facilities in Japan. Results: The SVM general performance results showed sensitivity of 88.71%, specificity of 83.78%, and an overall discrimination rate of 86.25%. Conclusion: A SVM using an objective index from RST may be useful as an auxiliary biomarker for diagnosis for children with ADHD.

Association of inattention with slow-spindle density in sleep EEG of children with attention deficit-hyperactivity disorder.

OBJECTIVE: We evaluated the power of slow sleep spindles during sleep stage 2 to clarify their relationship with executive function, especially with attention, in children with attention deficit-hyperactivity disorder (ADHD). METHODS: Subjects were 21 children with ADHD and 18 aged-matched, typically developing children (TDC). ADHD subjects were divided into groups of only ADHD and ADHD + autism spectrum disorder (ASD). We employed the Continuous Performance Test (CPT) to measure attention. We focused on sleep spindle frequencies (12-14 Hz) in sleep stage 2 and performed a power spectral analysis using fast Fourier transform techniques and compared sleep spindles with the variability of reaction time in CPT. RESULTS: In the CPT, reaction variabilities in ADHD and ADHD + ASD significantly differed from those in TDC. Twelve-hertz spindles were mainly distributed in the frontal pole and frontal area and 14-Hz spindles in the central area. The ratio of 12-Hz frontal spindle power was higher in ADHD than in TDC, especially in ADHD + ASD. Significant correlation between the ratio of 12-Hz spindles and reaction time variability was observed. CONCLUSIONS: Twelve-hertz frontal spindle EEG activity may have positive associations with sustained attention function. Slow frontal spindles may be useful as a biomarker of inattention in children with ADHD.

Age-related differences in frontal lobe function in children with ADHD.

BACKGROUND: The neural correlates of executive function disorders are thought to be predominantly localized within the prefrontal cortex (PFC). However, no study to date has investigated changes in this system across different age groups in children with attention deficit hyperactivity disorder (ADHD). Thus, this study aimed to explore changes in PFC function in children with ADHD. METHODS: Study participants included typically developing (TD) children (n = 140) and children with ADHD (n = 67) of primary school age. Behavioral executive functions and their neural basis were evaluated between the TD children and children with ADHD and also across different age periods (younger and older children). To examine executive function, inhibitory control was assessed using the reverse Stroop task, and PFC near-infrared spectroscopic measurements were used to investigate the neural mechanisms involved. RESULTS: Both ADHD symptoms and the ability to inhibit color interference improved with age. Compared to TD children, children with ADHD demonstrated decreased activation of the right and middle PFC across all age groups. Interestingly, the left PFC appeared to play a compensatory role. CONCLUSION: Children with ADHD exhibited changes in PFC function that varied with age. Longitudinal studies are required to assess the potential of using PFC function as an early biomarker of ADHD.

Modeling Training of Child's Echoic Conversational Response for Students with Autism Spectrum Disorder: To Be a Good Listener.

Students with autism spectrum disorder (ASD) often have difficulties in responding to conversation with verbal language. These students often repeat what they hear, and their echoic behavior has a potentially communicative function. We define the echoic behavior when an individual repeats a peer's topic word with appropriate prosody within 3 s as the child's echoic conversational response. In this study, we examined the acquisition of the child's echoic conversational response skills and whether these skills could provide and generalize natural conversation for 4 students with ASD. During the training, students were instructed to imitate the topic word that the experimenter had used in the latest conversation. Students learned the child's echoic conversational response skills and improved their conversation skills. They even showed a slight generalization for nontraining materials through trainings and improvements in responding with new verbal responses. These findings suggested that expanding speakers' repertoires for students with ASD might facilitate improvement of natural conversation skills.

Predictive factors of success in neurofeedback training for children with ADHD.

INTRODUCTION: Neurofeedback (NF) training aims the enhancement of self-regulation over brain activities. While it is largely recognized as an effective treatment for attention deficit hyperactivity disorder (ADHD), the existence of non-learners has also been reported. The present study explored pre-training assessment indices that could predict learners prior to NF training. METHODS: Twenty-two children with ADHD participated in slow cortical potential (SCP) NF training and completed pre- and post-training assessments. Participants were classified into learners or non-learners based on their progress in the SCP regulation, and pre-training indices that differentiate the two groups were examined by decision tree analysis. RESULTS AND DISCUSSION: The learner rate in NF training was 45.5%. Learners were predicted by pre-training cognitive and neurophysiological measures regarding Stroop tasks, which suggested relatively intact executive function as their characteristics. Given that NF training is not universally effective for children with ADHD, further studies are necessary to establish application criteria.

Sentence Reading Comprehension by Means of Training in Segment-Unit Reading for Japanese Children with Intellectual Disabilities.

Children with intellectual disabilities (ID) often have difficulty in sentence reading and comprehension. Previous studies have shown that training in segment-unit reading (SUR) facilitates the acquisition of sentence reading comprehension skills for Japanese students with ID. However, it remains unknown whether SUR training is also effective for individuals unable to read sentences and can generalize to untrained sentences. In this study, we examined the improvement and generalization of sentence reading accuracy and comprehension for two children with ID through SUR training with listening comprehensible sentences. During training, the segments were sequentially presented in their correct spatial locations, and participants read them aloud. After the training, participants' reading accuracy and comprehension improved for both trained and untrained sentences. The results suggest that presenting the components of stimuli sequentially in their correct spatial locations is key to facilitating the development of sentence reading accuracy and comprehension for individuals with ID.

Clinical utility of an array comparative genomic hybridization analysis for Williams syndrome.

To reveal the relation between intellectual disability and the deleted intervals in Williams syndrome, we performed an array comparative genomic hybridization analysis and standardized developmental testing for 11 patients diagnosed as having Williams syndrome based on fluorescent in situ hybridization testing. One patient had a large 4.2-Mb deletion spanning distally beyond the common 1.5-Mb intervals observed in 10/11 patients. We formulated a linear equation describing the developmental age of the 10 patients with the common deletion; the developmental age of the patient with the 4.2-Mb deletion was significantly below the expectation (developmental age = 0.51 × chronological age). The large deletion may account for the severe intellectual disability; therefore, the use of array comparative genomic hybridization may provide practical information regarding individuals with Williams syndrome.

Stimulus pairing training for Kanji reading skills in students with developmental disabilities.

Japanese students with developmental disabilities often exhibit difficulties in reading, particularly in Kanji (ideogram) reading, and in acquiring the equivalence relations between pictures, written words, and sounds. Previous research suggested that one student with autism could acquire Kanji reading along with equivalence relations through stimulus pairing training. However, maintenance rates tended to be very low, possibly due to the lack of picture stimuli. In this study, we examined the acquisition and maintenance of Kanji reading skills through stimulus pairing training using corresponding pictures for six students with developmental disabilities. We prepared stimulus pairs consisting of picture stimuli that the students could name along with a corresponding Kanji character that they could not read. All students successfully acquired and maintained the Kanji reading skills through this procedure. These findings suggest that the nameability of picture stimuli in stimulus pairing training may facilitate the acquisition and maintenance of equivalence relations for reading.