A comparative study on dietary diversity and gut microbial diversity in children with autism spectrum disorder, attention-deficit hyperactivity disorder, their neurotypical siblings, and non-related neurotypical volunteers: a cross-sectional study.

BACKGROUND: Previous research has shown a significant link between gut microbiota in children with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). However, much remains unknown because of the heterogeneity of disorders and the potential confounders such as dietary patterns and control group variations. METHODS: Children aged 6-12 years who had been clinically diagnosed with ASD and/or ADHD, their unaffected neurotypical siblings, and non-related neurotypical volunteers were recruited cross-sectionally. The ASD diagnosis was confirmed using the Autism Diagnostic Observation Schedule-2 (ADOS-2) in all patients, including those with ADHD. Standardized DNA extraction and sequencing methods were used to compare gut microbial alpha-diversity among the groups. Dietary diversity was calculated from a standardized dietary questionnaire form. We compared the difference in gut microbiome between patients with ASD and/or ADHD with neurotypical siblings and non-related neurotypical controls. RESULTS: Ninety-eight subjects were included in the study (18 with ASD, 19 with ADHD, 20 with both ASD and ADHD, 13 neurotypical siblings, and 28 non-related neurotypical controls). The alpha-diversity indices, such as Chao 1 and Shannon index, showed a significant difference between the groups in a Linear mixed-effect model (F(4, 93) = 4.539, p = .02), (F(4, 93) = 3.185, p = .017), respectively. In a post-hoc pairwise comparison, patients with ASD had lower alpha-diversity compared with non-related controls after Bonferroni correction. Dietary diversity shown in Shannon index did not differ among the groups (F(4, 84) = 1.494, p = .211). CONCLUSIONS: Our study indicates disorder-specific microbiome differences in patients with ASD. In future research on gut microbiota in neurodevelopmental disorders, it is necessary to consider the impact of ASD and ADHD co-occurrence, and strictly control for background information such as diet, to elucidate the gut-microbiota interaction in ASD and ADHD for exploring the potential of therapeutic interventions.

Infants' interoception is associated with eye contact in dyadic social interactions.

Interoception, that is, the perception of visceral stimuli, is the basis of socio-emotional development. However, no studies have demonstrated the relationship between the two in infants. This study aimed to elucidate the relationship between interoception and social behavior in infants and mothers. Visual preference for cardio-visual synchronous and asynchronous stimuli was assessed using a preferential-looking paradigm in 6-month infants and their mothers. The infant-mother interaction was also measured to assess social behavior, such as eye contact and positive facial expressions. The results showed that infants looked at asynchronous cardio-visual stimuli longer than synchronous cardio-visual stimuli, whereas mothers looked at synchronous cardio-visual stimuli longer than asynchronous cardio-visual stimuli. The proportion of looking time toward asynchronous cardio-visual stimuli in infants was positively correlated with infant-mother gaze and affect (positive facial expression) synchrony. Furthermore, mediation analyses showed that the relationship between infants' interoception and eye contact behavior is attributable to mother's positive facial expression. Our findings suggest that in infant-mother interactions, infants' interoception may play a role in eye contact behavior through the mother's positive facial expression, highlighting the importance of infants' interoception on social cognitive development.

Impact of mindfulness tendency and physical activity on brain-gut interactions.

BACKGROUND: Irritable bowel syndrome (IBS) is a disorder of brain-gut interactions characterized by abdominal pain and bowel dysfunction. Exercise and mindfulness have been reported to be effective on IBS, but there has been no study of their interaction. In this study, we hypothesized that exercise and mindfulness interactively affect the severity of IBS symptoms. METHODS: Subjects were 703 adolescents with 590 women and 113 men. Their IBS status was evaluated with Rome III Diagnostic Questionnaire and IBS Severity Index (IBS-SI). They also fulfilled past exercise experience, athletic performance and exercise enthusiasm, International Physical Activity Questionnaire (IPAQ), Mindful Attention Awareness Scale (MAAS), Kessler 6 Scale (K6), and Perceived Stress Scale (PSS). Statistical analysis was performed using SPSS v25. RESULTS: In this population, 184 (158 women and 26 men, 14.1%) subjects had Rome III IBS symptoms. IBS subjects scored significantly less in exercise enthusiasm at high school (p = 0.017) and MAAS (p < 0.001) and significantly more K6 (p < 0.001) and PSS (p < 0.001) than non-IBS. The two-way ANOVA on IBS-SI showed a significant main effect of MAAS (p < 0.001) and interaction between MAAS and IPAQ (p = 0.008). CONCLUSION: It is suggested that mindfulness per se decreases IBS severity, but that mindfulness and physical activity interactively affect the severity. Further studies on how to design interventional trials for IBS patients with mindfulness and physical exercise are warranted.

Cognitive flexibility in 12-month-old preterm and term infants is associated with neurobehavioural development in 18-month-olds.

There is growing evidence that preterm children are at an increased risk of poor executive functioning, which underlies behavioural and attention problems. Previous studies have suggested that early cognitive flexibility is a possible predictor of later executive function; however, how it develops in infancy and relates to the later neurobehavioural outcomes is still unclear in the preterm population. Here, we conducted a longitudinal study to investigate oculomotor response shifting in 27 preterm and 25 term infants at 12 months and its relationship with general cognitive development and effortful control, which is a temperamental aspect closely associated with executive function, at 18 months. We found that moderate to late preterm and term infants significantly inhibited previously rewarded look responses, while very preterm infants did not show significant inhibition of perseverative looking at 12 months. Moreover, lower inhibition of perseverative looking was significantly associated with lower general cognitive development and attentional shifting at 18 months. These findings suggest that the early atypical patterns of oculomotor response shifting may be a behavioural marker for predicting a higher risk of negative neurobehavioural outcomes, including attention-related problems in preterm children.

Importance of Maternal Persistence in Young Children's Persistence.

Persistence of a distant goal is an important personality trait that determines academic and social success. Recent studies have shown that individual differences in persistence involve both genetic and environmental factors; however, these studies have not examined the role of maternal factors on a young children's persistence. The present study examined whether mothers' persistence is associated with persistence in children aged 3-6 years. In addition, the associations between mothers' persistence/parenting style and children's self-control/social development (prosocial behaviors and difficulties) were examined. Our results showed that maternal persistence is essential for the child's persistence. Children's self-control and social development were also associated with the mothers' persistence and parenting style. Our findings suggest that a young child's persistence may develop under the influence of a familiar adult (i.e., mother) and characterizes their social development, highlighting the importance of persistence in parenting.

Longitudinal assessment of social attention in preterm and term infants: Its relation to social communication and language outcome.

Preterm birth has been reported to be associated with an increased risk of social communication and language problems. Recently, we found that preterm infants showed atypical patterns of social attention compared with term infants. However, it is still unknown how social attention develops and whether the individual differences are associated with developmental outcomes for social communication and language in preterm infants. The social attention of preterm and term infants at 6, 12, and 18 months was investigated using two types of social attention tasks (human-geometric preference task and gaze-following task). The Modified Checklist for Autism in Toddlers (M-CHAT) and the MacArthur Communicative Development Inventory adapted for Japanese were measured at 18 months. We found that compared with term infants, preterm infants spent less time looking toward dynamic human images and followed another's gaze directions less frequently through 6, 12, and 18 months. Moreover, hierarchical multiple regression analysis revealed that less preference for dynamic human images and gaze-following abilities was associated with high M-CHAT and low language scores in preterm and term infants, respectively. These findings suggest that birth status affects development of social attention through 18 months and individual differences in social attention reflect differences in social communication and language outcomes.

Interoception is associated with the impact of eye contact on spontaneous facial mimicry.

Interoception (perception of one's own physiological state) has been suggested to underpin social cognition, although the mechanisms underlying this association remain unclear. The current study aimed to elucidate the relationship between interoception and two factors underlying social cognition: self-other boundary and sensitivity to social cues. We measured performance in a heartbeat perception task as an index of interoceptive accuracy (IAc), the frequency of spontaneous facial mimicry (SFM) as an index of self-other boundary, and the degree of the effect of eye contact on SFM (difference in SFM between conditions in which models' eyes were directed to and averted from participants) as an index of social-cue sensitivity, and tested correlations among these measures. The results revealed that IAc and SFM were positively correlated only in the direct gaze condition. The extent of the effect of eye contact on SFM (difference in frequency between direct vs. averted conditions) was positively correlated with IAc. These overall findings were also observed in separate analyses of male and female participant groups, supporting the robustness of the findings. The results suggest that interoception is related to sensitivity to social cues, and may also be related to the self-other boundary with modulation by social context.

Difference in neural reactivity to taste stimuli and visual food stimuli in neural circuits of ingestive behavior.

Brain responses to sight and taste of foods have been examined to provide insights into neural substrates of ingestive behavior. Since the brain response to food images and taste stimuli are overlapped in neural circuits of eating behavior, each food cue would influence eating behavior in a partly similar manner. However, because few studies have examined the differences in brain responses to each food cue, the variation in neural sensitivity to these food cues or specific brain response to each food cue remain unclear. We thus performed a repeated measures functional magnetic resonance imaging (fMRI) study to examine brain responses to the image and taste of various foods for direct comparisons of the brain response to each food cue. Thirty-five healthy adolescents (age: 14-19 years [mean: 17 years], males = 16, females = 19) underwent two fMRI scans, a food image fMRI scan for measurement of brain response to food images, and a taste stimulus fMRI scan for measurement of brain response to taste stimuli. Food images evoked brain responses in the visual information processing regions, anterior insula, striatum, and pre-/postcentral gyrus compared to taste stimuli, whereas taste stimuli induced brain responses in the mid-insula and limbic regions compared to food images. These results imply that food images tend to evoke brain responses in regions associated with food reward anticipation and food choice, whereas taste stimuli tend to induce brain responses in regions involved in assigning existent incentive values to foods based on existent energy homeostatic status.

Demystifying infant vocal imitation: The roles of mouth looking and speaker's gaze.

Vocal imitation plays a fundamental role in human language acquisition from infancy. Little is known, however, about how infants imitate other's sounds. We focused on three factors: (a) whether infants receive information from upright faces, (b) the infant's observation of the speaker's mouth and (c) the speaker directing their gaze towards the infant. We recorded the eye movements of 6-month-olds who participated in experiments watching videos of a speaker producing vowel sounds. We found that an infants' tendency to vocally imitate such videos increased as a function of (a) seeing upright rather than inverted faces, (b) their increased looking towards the speaker's mouth and (c) whether the speaker directed their gaze towards, rather than away from infants. These latter findings are consistent with theories of motor resonance and natural pedagogy respectively. New light has been shed on the cues and underlying mechanisms linking infant speech perception and production.

Audiovisual speech perception and language acquisition in preterm infants: A longitudinal study.

BACKGROUND: Preterm infants have a higher risk of language delay throughout childhood. The ability to integrate audiovisual speech information is associated with language acquisition in term infants; however, the relation is still unclear in preterm infant. AIM AND METHODS: This study longitudinally investigated visual preference for audiovisual congruent and incongruent speech during a preferential looking task using eye-tracking in preterm and term infants at 6, 12, and 18 months of corrected age. The infants' receptive and expressive vocabulary at 12 and 18 months were obtained by parent report, using the Japanese MacArthur Communicative Development Inventory. RESULTS: We found that preterm infants did not clearly show visual preference for the congruent audiovisual display at any age, whereas term infants looked at the congruent audiovisual display longer than the incongruent audiovisual display at 6 and 18 months. Preterm infants' receptive and expressive vocabulary scores were lower than those of term infants at 12 and 18 months. Furthermore, the proportion of looking time toward the congruent audiovisual display at 6 months was positively correlated with receptive vocabulary scores at 12 and 18 months for both groups. CONCLUSIONS: These findings suggest that better audiovisual speech perception abilities are one factor that results in better language acquisition in preterm as well as term infants. Early identification of behaviors associated with later language in preterm infants may contribute to planning intervention for developmental problems.

Fundamental Frequency Variation of Neonatal Spontaneous Crying Predicts Language Acquisition in Preterm and Term Infants.

Spontaneous cries of infants exhibit rich melodic features (i.e., time variation of fundamental frequency [F0 ]) even during the neonatal period, and the development of these characteristics might provide an essential base for later expressive prosody in language. However, little is known about the melodic features of spontaneous cries in preterm infants, who have a higher risk of later language-related problems. Thus, the present study investigated how preterm birth influenced melodic features of spontaneous crying at term-equivalent age as well as how these melodic features related to language outcomes at 18 months of corrected age in preterm and term infants. At term, moderate-to-late preterm (MLP) infants showed spontaneous cries with significantly higher F0 variation and melody complexity than term infants, while there were no significant differences between very preterm (VP) and term infants. Furthermore, larger F0 variation within cry series at term was significantly related to better language and cognitive outcomes, particularly expressive language skills, at 18 months. On the other hand, no other melodic features at term predicted any developmental outcomes at 18 months. The present results suggest that the additional postnatal vocal experience of MLP preterm infants increased F0 variation and the complexity of spontaneous cries at term. Additionally, the increases in F0 variation may partly reflect the development of voluntary vocal control, which, in turn, contributes to expressive language in infancy.

Preference for Dynamic Human Images and Gaze-Following Abilities in Preterm Infants at 6 and 12 Months of Age: An Eye-Tracking Study.

Preterm children are reported to be at higher risk of social communication problems such as autism spectrum disorder compared with full-term infants. Although previous studies have suggested that preference for social stimuli in infancy is a possible indicator of later social communication development, little is known about this relation in preterm infants. We examined the gaze behavior of low-risk preterm and full-term infants at 6 and 12 months' corrected ages using two types of eye-tracking tasks, which measured 1) preference for social stimuli by biological motion and human geometric preference and 2) ability to follow another's gaze direction. We found that preterm (compared with full-term) infants at both 6 and 12 months of age spent less time looking toward dynamic human images, followed another's gaze less frequently, and looked for a shorter time at an object cued by another. Moreover, we found a positive correlation between looking time toward dynamic human images and frequency of gaze following at 12 months of age in full-term, but not preterm, infants. We discuss the relation between the atypical patterns of gaze behavior in preterm infants and their higher risk of later social communication problems.

"Mom called me!" Behavioral and prefrontal responses of infants to self-names spoken by their mothers.

Development of a sense of self is a fundamental process needed for human social interaction. Although functional neuroimaging studies have revealed the importance of medial prefrontal cortex (mPFC) in self-referencing, how this function develops in infancy remains poorly understood. To determine the cerebral basis underlying processing of self-related stimuli, we used behavioral measures and functional multi-channel near-infrared spectroscopy (fNIRS) to measure prefrontal cortical responses in 6-month-old infants hearing their own names. We also investigated the influence of a mother's voice on name perception in infants - an ability that plays a crucial role in the recognition of social signals. Experiment 1 measured the behavioral preferences of infants for their own names and for other names, spoken either by their mothers or by strangers. Results showed that infants significantly preferred their own name to other names, regardless of speaker type. Experiment 2 examined hemodynamic responses to the same four conditions in the prefrontal cortex. Compared with other names, hearing their own names, especially when spoken by their mother, elicited greater activity in the infant's dorsal mPFC. Furthermore, the magnitude of the cerebral response correlated with the degree of behavioral preference only when involving their mother's voice. These findings suggest that, particularly in the context of their mothers' voice, the dorsal mPFC of infants is already sensitive to social signals related to self at 6 months. At the same time, familiarity and affection related processing are also discussed as possible factors modulating dorsal mPFC activation at this age.