"Picture this from there": spatial perspective-taking in developmental visuospatial disorder and developmental coordination disorder.

Introduction: Either Developmental Visuospatial Disorder (DVSD) and Developmental Coordination Disorder (DCD) present with difficulties in visuospatial processing, even though entailing different degrees of impairment. Among the visuospatial domain, spatial perspective taking is essential to interact with the environment and is significantly involved in many daily activities (e.g., environment navigation and spatial orienting). Notwithstanding, no previous studies have investigated this spatial domain in children with DVSD and limited evidence is available regarding DCD. Consistent with a transdiagnostic approach, the first goal of the present study was to compare spatial perspective taking abilities of these groups, also including a control group of not diagnosed peers (ND). Secondly, the role of different fine-motor and visuo-spatial predictors on the spatial perspective taking performance was considered. Method: A total of 85 participants (DVSD = 26; DCD = 26; ND = 33), aged between 8 and 16 years old, were included in the study. Tasks assessing spatial perspective taking, fine-motor, visual imagery, and mental rotation skills, as well as visuo-spatial working memory were administered. Results and Discussion: Overall, our results confirmed weaknesses in spatial perspective taking in both clinical groups, with the DVSD obtaining the lowest scores. Similarities and differences in the predictors accounting for the performance in the spatial perspective taking task emerged, suggesting the possible employment of different fine-motor or visuospatial strategies by group. Findings are discussed considering the potential impact they may have both in research and clinical practice.

Social Functioning in Children and Adolescents with ADHD and Autism Spectrum Disorder: A Cross-Disorder Comparison.

OBJECTIVE: Social functioning can be defined according to three main components: social perception, social performance, and social knowledge. Although they are important in daily life relationships and in children's adaptation, these components have never been tested together in children and adolescents with Attention Deficit/Hyperactivity Disorder (ADHD) or with Autism Spectrum Disorder (ASD) using lab-based tasks. The present study used a cross-disorder approach to compare the performance of children with ADHD and ASD and non-diagnosed (ND) peers utilizing a task that involves these three fundamental social functioning components. METHODS: Two hundred and twenty-five Italian children (86% boys) aged between 8 and 16 (66 with a clinical diagnosis of ADHD; 51 with a clinical diagnosis of ASD, level 1; 108 ND children) were enrolled. The three groups were matched for age, gender, and IQ. Social functioning was assessed using a lab-based task, including videos of problematic interactions among peers, created ad hoc for the study, and a semi-structured interview based on the Social Information Processing model. RESULTS: Data were analyzed using one-way ANOVAs and multinomial mixed effects models. Our findings suggested that both groups with ADHD and ASD presented social functioning difficulties in comparison to ND children. However, a different pattern of performance emerged. Children with ADHD showed higher difficulties in social performance than those with ASD, whereas autistic children revealed more difficulties in social perception and in some aspects of social knowledge. CONCLUSIONS: Our findings have important clinical implications for assessment, intervention, and differential diagnosis, and should encourage clinicians to investigate different aspects of social functioning and identify specific strengths and weaknesses in each social profile.

Let's face it! The role of social anxiety and executive functions in recognizing others' emotions from faces: Evidence from autism and specific learning disorders.

Youth with different developmental disorders might experience challenges when dealing with facial emotion recognition (FER). By comparing FER and related emotional and cognitive factors across developmental disorders, researchers can gain a better understanding of challenges and strengths associated with each condition. The aim of the present study was to investigate how social anxiety and executive functioning might underlie FER in youth with and without autism spectrum disorders (ASD) and specific learning disorders (SLD). The study involved 263 children and adolescents between 8 and 16 years old divided into three groups matched for age, sex, and IQ: 60 (52 M) with ASD without intellectual disability, 63 (44 M) with SLD, and 140 (105 M) non-diagnosed. Participants completed an FER test, three executive functions' tasks (inhibition, updating, and set-shifting), and parents filled in a questionnaire reporting their children's social anxiety. Our results suggest that better FER was consistent with higher social anxiety and better updating skills in ASD, while with lower social anxiety in SLD. Clinical practice should focus on coping strategies in autistic youth who could feel anxiety when facing social cues, and on self-efficacy and social worries in SLD. Executive functioning should also be addressed to support social learning in autism.

Trajectory assessments of cognitive, visuospatial, and academic profile in nonverbal learning disability (visuospatial developmental disorder).

Substantial progress has been made in defining children with nonverbal learning disability (NLD), but longitudinal studies are still lacking. To start filling this gap, we examined changes in general cognitive functioning, visuo-constructive skills, and academic profiles in a group of children with NLD, also taking into account any internalizing and externalizing symptom as transdiagnostic features. A total of 30 participants (24 boys) diagnosed with NLD were tested twice, with a three-year gap between the two assessments (T1: at age 8-13; T2: at 11-16), on their cognitive profile, visuospatial abilities, and academic performance (i.e., reading, writing and arithmetic abilities). At T2, any internalizing and externalizing symptom was also investigated. Statistically significant differences emerged between the two assessments in terms of the WISC-IV Perceptual Reasoning Index (PRI), handwriting speed and arithmetical fact retrieval. The NLD profile seems to be characterized by a relative stability in its core features during a child's development, as regards both weaknesses (i.e., visuospatial processing) and strengths (i.e., verbal abilities). The presence of internalizing and externalizing symptoms also suggested the importance to analyze transdiagnostic features rather than only sharp boundaries between conditions.

Social perception in children and adolescents with ADHD: The role of higher-order cognitive skills.

Despite children with ADHD frequently experiencing difficulties in social perception, the mechanisms underlying this impairment have been poorly explored. In this study, we examined social perception in children with ADHD, comparing them with typically-developing (TD) children on semi-naturalistic tasks, and considering the effect of nonverbal signal recognition. Our aim was to ascertain whether the two groups' social perception related to different types of stimulus (video, audio or combined/multimodal). The role of three higher-order cognitive skills (theory of mind, attention and pragmatic language) was also investigated. Thirty-six children with ADHD, and 36 TD controls were tested. Social perception was significantly associated with participants' ability to recognize nonverbal signals, and with the stimulus presentation modality. Children with ADHD only performed less well than TD children with combined stimuli. As concerns the higher-order cognitive skills, theory of mind had a significant role in both groups, but only with the video and combined stimuli, while attention explained most of the variance in social perception for all types of stimulus. Better pragmatic language skills were only associated with a better social perception in TD children, whatever the type of stimulus presented. Semi-naturalistic tasks should be included when assessing social perception in ADHD, and both theory of mind and attention should be the object of efforts to enhance social perception in the ADHD population.

Do comorbid symptoms discriminate between autism spectrum disorder, ADHD and nonverbal learning disability?

Characterizing the functioning of individuals with neurodevelopmental disorders is crucial to their diagnosis. Research has found that children with different neurodevelopmental disorders, including autism spectrum disorders (ASD), attention deficit and hyperactivity disorder (ADHD), and nonverbal learning disability (NLD), may have comorbid symptoms of anxiety and depression, and problems with pragmatic language. The main aim of the present study was to identify any differences in the above-mentioned comorbid symptoms associated with these clinical profiles. A second aim was to establish how well signs of pragmatic language difficulties could discriminate between the three clinical profiles, in terms of their diagnostic power. For this purpose, 107 participants from 8 to 16 years old with a diagnosis of ASD, ADHD or NLD were compared with a group of typically-developing children. Self-reports on symptoms of anxiety and depression, and parents' reports on social and communication problems were analyzed. Our findings confirmed that symptoms of anxiety and depression, and problems with pragmatic language are associated with different neurodevelopmental disorders, but not in the same way. In terms of diagnostic power, we found that pragmatic language difficulties clearly discriminated children with ASD, ADHD or NLD from typically-developing children. Importantly, pragmatic language difficulties also discriminated adequately between ASD and NLD. Our findings are discussed in terms of the value of considering comorbid symptoms to obtain a more accurate diagnosis of neurodevelopmental disorders.

Do children with and without autism spectrum disorder use different visuospatial processing skills to perform the Rey-Osterrieth complex figure test?

Visuospatial organization abilities are closely related to other visuospatial processing skills, such as visuomotor coordination, perceptual abilities, mental rotation, and working memory (WM). One task that enables visuospatial organization abilities to be investigated is the Rey-Osterrieth complex figure test (ROCFT). When examining visuospatial functioning, individuals with autism spectrum disorder (ASD) have proved capable of operating both locally and globally, depending on the sub-domain embraced, with a preference for a locally-oriented processing of visuospatial information. The present research aimed to establish whether different underlying visuospatial skills might account for performance in the ROCFT in children and adolescents with ASD, compared with typically developing (TD), by considering the role of local/global visuospatial processing. The study involved 39 participants who have ASD without intellectual disability, and 57 TD aged 8-16 years. The participants were administered tasks assessing visuospatial organization abilities, manual dexterity, visual perception, mental rotation, spatial-sequential, spatial-simultaneous WM, and visuospatial processing. Our results suggest that manual dexterity and visuospatial processing similarly explain performance in both groups, while differences in visuospatial WM account for the two groups' visuospatial organization abilities. Spatial-simultaneous WM predicted performance in copy and recall conditions in the TD group but not in the ASD group, while spatial-sequential WM only did so in the latter group, reinforcing the tendency of children with ASD towards local bias in the visuospatial organization domain. The implications of these findings are discussed. LAY SUMMARY: The visuospatial organization abilities of children and adolescents with and without autism were compared, considering their underlying visuospatial skills. Visuospatial organization impairments emerged for children with autism, who differed from typically developing children in the underlying visuospatial skills involved. Given the crucial role of visuospatial organization abilities in everyday life, our results could inspire practitioners to develop training interventions that take into account the strengths and weaknesses of individuals with autism.

Research Review: Language and specific learning disorders in children and their co-occurrence with internalizing and externalizing problems: a systematic review and meta-analysis.

BACKGROUND: Some studies suggest that children with language and learning disorders (LLDs) show more internalizing and externalizing problems than their peers. However, the available evidence remains inconsistent, especially regarding the conditions under which these psychological problems occur. METHODS: We performed a meta-analysis of studies comparing children with LLDs and controls on internalizing (53 independent samples, 135 effect sizes) and externalizing problems (37 independent samples, 61 effect sizes) separately. RESULTS: Children with LLDs showed higher internalizing (Hedges' g = 0.36) and externalizing problems (Hedges' g = 0.42) than controls did. The group standardized difference in internalizing problems was moderated by the primary disorder, with children with language disorders showing more internalizing problems than those with reading disorders. The severity of the primary disorder, IQ, and age did not moderate Hedge's g between children with LLDs and controls in internalizing and externalizing outcomes. The same pattern was found for gender as a moderator of Hedge's g in internalizing problems, while findings for externalizing problems were inconclusive. The results were consistent when methodological variables were assessed, also for informant, sample size, and geographical area. Clinical samples with LLDs reported higher internalizing problems respect to those with difficulties, but findings on externalizing outcomes were limited. Similarly, results on the presence of additional symptoms in learning and language, self-concept, and socioeconomic status were inconclusive, as few studies reported this information. Results were robust when publication bias, publication year, and study quality were assessed. CONCLUSIONS: There is evidence that children with LLDs report higher internalizing and externalizing problems than controls do. Children with language disorders seemed more vulnerable to report more internalizing problems, and clinical samples reported higher problems than those with difficulties. For clinical practice, assessment and interventions should target socioemotional skills to support the psychological well-being of children with LLDs.

The Processes Underlying Positive Illusory Bias in ADHD: The Role of Executive Functions and Pragmatic Language Skills.

OBJECTIVE: Children with ADHD often show a positive illusory bias (PIB), reporting an extremely positive idea of their own competence, despite their difficulties. The mechanisms underlying this phenomenon are still poorly understood. In the present study, we examined social PIB and investigated the role of executive functions (EFs) and pragmatic language (PL). METHOD: Forty-one children with ADHD and 42 typically-developing children matched on age, IQ, and receptive language were administered measures of social competence, EFs and PL. The parents were also asked to estimate their child's social competence. RESULTS: There was evidence of social difficulties and PIB in children with ADHD. Only PL, not EFs, seemed to mediate the association between ADHD and PIB. CONCLUSION: Our findings suggest that PL abilities should be considered in efforts to improve self-perception in children with ADHD.

Executive Functions in Neurodevelopmental Disorders: Comorbidity Overlaps Between Attention Deficit and Hyperactivity Disorder and Specific Learning Disorders.

The present study examines the comorbidity between specific learning disorders (SLD) and attention deficit and hyperactivity disorder (ADHD) by comparing the neuropsychological profiles of children with and without this comorbidity. Ninety-seven schoolchildren from 8 to 14 years old were tested: a clinical sample of 49 children with ADHD (n = 18), SLD (n = 18) or SLD in comorbidity with ADHD (n = 13), and 48 typically-developing (TD) children matched for age and intelligence. Participants were administered tasks and questionnaires to confirm their initial diagnosis, and a battery of executive function (EF) tasks testing inhibition, shifting, and verbal and visuospatial updating. Using one-way ANOVAs, our results showed that all children in the clinical samples exhibited impairments on EF measures (inhibition and shifting tasks) when compared with TD children. A more specific pattern only emerged for the updating tasks. Only children with SLD had significant impairment in verbal updating, whereas children with ADHD, and those with SLD in comorbidity with ADHD, had the worst performance in visuospatial updating. The clinical and educational implications of these findings are discussed.

Pragmatic Language in Children and Adolescents With Autism Spectrum Disorder: Do Theory of Mind and Executive Functions Have a Mediating Role?

Pragmatic language (PL) is defined as the ability to use language effectively in communicative exchanges. Previous findings showed that deficits in PL are a core characteristic of the communicative profile of individuals with autism spectrum disorder (ASD). While different lines of research have revealed a close link between PL and theory of mind (ToM), and between PL and executive functions (EFs), to our knowledge, few studies have explored the relationship between these three domains in children with ASD, and their results have been contradictory. The present study thus aimed to contribute to our understanding of PL in children with ASD and to analyze the underlying mediating role of ToM and EFs. PL is a complex and multifaceted construct. In the present study, we focused on two specific aspects, such as the comprehension of nonliteral language, and the ability to make inferences. After testing 143 participants (73 with ASD), our results confirmed that impairments in PL are a crucial feature of the ASD profile. Children with ASD were also more impaired than their typically developing peers in both ToM and EFs. When the mediating role of ToM and EFs on PL was considered, it emerged that only ToM contributed significantly to the relationship between group and PL. We discussed the potential importance of interventions not focused exclusively on PL, but also involving ToM. LAY SUMMARY: In everyday life, we use pragmatic language to interact successfully with others. Individuals with autism experience significant difficulty in pragmatic language, showing consequent impairments in communication. This study compared the comprehension of nonliteral language, and the ability to make inferences of children with autism and children with typical development, focusing on the role of social and cognitive abilities. Children with autism had difficulties in pragmatic language compared to children with typical development. In addition, the capacity to consider the perspective, intentions and beliefs of other people contributed significantly to the pragmatic language. Autism Res 2021, 14: 932-945. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

Spatial Perspective-Taking in Children With Autism Spectrum Disorders: The Predictive Role of Visuospatial and Motor Abilities.

Despite its impact on everyday functioning, spatial perspective-taking has rarely been investigated in autism spectrum disorders (ASD), and previous findings are surprisingly sparse and inconsistent. In the present study, we aimed to investigate spatial perspective-taking abilities in children and adolescents with ASD without intellectual disabilities, comparing them with a group of typically developing (TD) peers. Our objectives were: (i) to test similarities and differences between these groups in a spatial perspective-taking task; and (ii) to see whether similar or different underlying processes (i.e., fine and gross motor skills, and visuospatial abilities) might account for the groups' performance in the spatial perspective-taking task. A group of children with ASD (N = 36) was compared with a TD group (N = 39), aged from 8 to 16 years. Participants were administered tasks assessing spatial perspective-taking, fine and gross motor skills, visuo-constructive abilities, visuospatial working memory, visual imagery, and mental rotation. Our results revealed that the ASD group had more difficulty with the spatial perspective-taking task than the TD group. The two groups also had some shared and some different processes that predicted their perspective-taking performance: a significant predictive effect of fine motor skills and visuospatial working memory emerged for both groups, while gross motor skills (i.e., walking heel-to-toe) and visuospatial imagery only revealed a role in the TD group. These findings suggest that different abilities might account for the two groups' performance in the spatial perspective-taking task. Gross motor skills and complex visuospatial abilities seem to be more important in sustaining spatial perspective-taking ability in typical development than in the event of ASD. Some of the clinical and educational implications of these findings are discussed.

A comparison of local-global visuospatial processing in autism spectrum disorder, nonverbal learning disability, ADHD and typical development.

BACKGROUND: Research on visuospatial functioning has revealed cognitive challenges for children with autism spectrum disorder (ASD), nonverbal learning disability (NLD) and attention deficit hyperactivity disorder (ADHD). These disorders are characterized by some overlapping symptoms, making their diagnosis a challenge. AIMS: The study aims to clarify the role of visuospatial abilities in their neuropsychological profiles by investigating different visuospatial domains and their interplay with the local-global processing. METHOD AND PROCEDURES: Participants (N = 150) with ASD, NLD, or ADHD were compared with typically-developing (TD) children on visuospatial processing speed, visuo-perceptual abilities, visuo-constructive abilities, and visuospatial working memory. Generalized mixed-effects models were performed and receiver operating characteristic curves were estimated to express the usefulness of a local-global processing index in discriminating groups. OUTCOMES AND RESULTS: The NLD group was impaired in all domains; children with ADHD revealed a heterogeneous profile, with greater impairments in visuospatial processing speed; ASD and TD groups were comparable. The local-global processing index had predictive power in discriminating among groups in visuo-constructive task. CONCLUSIONS AND IMPLICATIONS: The study of visuospatial abilities of children with ASD, NLD and ADHD might help to understand strengths and weaknesses in their neuropsychological profile and to differentiate between them. Clinical implications of these findings are discussed.

A cross-task comparison on visuospatial processing in autism spectrum disorders.

This study aimed to draw a cross-task comparison on visuospatial processing in autism spectrum disorder without intellectual disability. Participants with autism spectrum disorder were matched with typically developing individuals on general intelligence and perceptual reasoning index. The two groups were subsequently compared on visuospatial processing speed, visuo-perceptual, visuo-constructive, and visuospatial working memory tasks. Our results revealed similar performances between autism spectrum disorder and typically developing individuals on measures of visuospatial processing speed and visuospatial working memory. The autism spectrum disorder group showed slower reaction times than the typically developing group in the visuo-perceptual task, when stimuli were characterized by a minimum level of perceptual cohesiveness, revealing weaker spatial integration abilities. Concerning the visuo-constructive domain, no differences between the autism spectrum disorder and the typically developing group emerged for the unsegmented condition, revealing that our participants with autism spectrum disorder were similar to the typically developing group in the local analysis of the stimuli. The discussion takes into account the role of individual differences on visuospatial intelligence, task requirements, and cognitive domains to clarify the visuospatial processing skills of individuals with autism spectrum disorder.

Differences in visuospatial processing in individuals with nonverbal learning disability or autism spectrum disorder without intellectual disability.

OBJECTIVE: Although previous reports produced converging empirical evidence of a core deficit on visuospatial processing in children with a nonverbal learning disability (NLD), few studies compared the visuospatial profile of individuals with an autism spectrum disorder (ASD) or NLD in visuoconstructive and visuospatial working memory tasks. Nor did any of these studies investigate the role of the local bias, typically observed in ASD, when comparing these clinical groups. The present study aimed to analyze whether NLD and ASD share any characteristics. METHOD: A group of participants with NLD (n = 17) was compared with another group who had ASD (n = 17) without intellectual disability (ID), and without a peak in visuospatial intelligence, and with a control group (n = 17). Participants aged from 8 to 18 years performed a visuoconstructive and a visuospatial working memory task in which global-local processing styles were manipulated. RESULTS: The analysis of their visuospatial processing clearly distinguished between the neuropsychological profiles of the group with ASD without ID and the group with NLD: the latter performed less well than the former in all domains. The participants with ASD without ID had a more heterogeneous visuospatial profile, showing a diminished sensitivity to perceptual cohesiveness only in the visuoconstructive task. CONCLUSIONS: Examining different visuospatial domains and manipulating the cohesiveness of the stimuli might be useful for better discriminating between NLD and ASD without ID. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Visuoconstructive abilities and visuospatial memory in autism spectrum disorder without intellectual disability: Is the role of local bias specific to the cognitive domain tested?

OBJECTIVE: Visuospatial processing in autism spectrum disorder (ASD) without intellectual disability remains only partly understood. The aim of the present study was to investigate global versus local visuospatial processing in individuals with ASD, comparing them with typically developing (TD) controls in visuoconstructive and visuospatial memory tasks. METHOD: There were 21 participants with ASD without intellectual disability, and 21 TD controls matched for chronological age (M = 161.37 months, SD = 38.19), gender, and perceptual reasoning index who were tested. Participants were administered tasks assessing the visuoconstructive domain and involving fine motor skills, and visuospatial memory tasks in which visuospatial information had to be manipulated mentally. RESULTS: Using a mixed-effects model approach, our results showed different effects of local bias in the ASD group, depending on the domain considered: the use of a local approach only emerged for the visuoconstructive domain-in which fine motor skills were involved. CONCLUSIONS: These results seem to suggest that the local bias typical of the cognitive profile of ASD without intellectual disability could be a property of specific cognitive domains rather than a central mechanism. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Pragmatics of language and theory of mind in children with dyslexia with associated language difficulties or nonverbal learning disabilities.

The present study aims to find empirical evidence of deficits in linguistic pragmatic skills and theory of mind (ToM) in children with dyslexia with associated language difficulties or nonverbal learning disabilities (NLD), when compared with a group of typically developing (TD) children matched for age and gender. Our results indicate that children with dyslexia perform less well than TD children in most of the tasks measuring pragmatics of language, and in one of the tasks measuring ToM. In contrast, children with NLD generally performed better than the dyslexia group, and performed significantly worse than the TD children only in a metaphors task based on visual stimuli. A discriminant function analysis confirmed the crucial role of the metaphors subtest and the verbal ToM task in distinguishing between the groups. We concluded that, contrary to a generally-held assumption, children with dyslexia and associated language difficulties may be weaker than children with NLD in linguistic pragmatics and ToM, especially when language is crucially involved. The educational and clinical implications of these findings are discussed.

Local and global processing in block design tasks in children with dyslexia or nonverbal learning disability.

Visuo-constructive and perceptual abilities have been poorly investigated in children with learning disabilities. The present study focused on local or global visuospatial processing in children with nonverbal learning disability (NLD) and dyslexia compared with typically-developing (TD) controls. Participants were presented with a modified block design task (BDT), in both a typical visuo-constructive version that involves reconstructing figures from blocks, and a perceptual version in which respondents must rapidly match unfragmented figures with a corresponding fragmented target figure. The figures used in the tasks were devised by manipulating two variables: the perceptual cohesiveness and the task uncertainty, stimulating global or local processes. Our results confirmed that children with NLD had more problems with the visuo-constructive version of the task, whereas those with dyslexia showed only a slight difficulty with the visuo-constructive version, but were in greater difficulty with the perceptual version, especially in terms of response times. These findings are interpreted in relation to the slower visual processing speed of children with dyslexia, and to the visuo-constructive problems and difficulty in using flexibly-experienced global vs local processes of children with NLD. The clinical and educational implications of these findings are discussed.

The role of practice and strategy in mental rotation training: transfer and maintenance effects.

Research in the domain of spatial abilities is now focusing on whether spatial abilities can be trained, and whether this can produce gains and maintenance effects in other, untrained skills. The aim of the present study was to assess the benefit and maintenance effects of two types of mental rotation training, one based on mental rotation practice alone, the other combining mental rotation practice with the use of a spatial (rotation) strategy. Seventy-two females took part in the study: 24 practiced with a rotation task that involved comparing pairs of 3D objects [the mental rotation (MR) group], 24 were taught to use the rotation strategy while practicing with the rotation task [the strategy + mental rotation (S + MR) group], and 24 were involved in parallel non-spatial activities (the active control group). Transfer effects were sought on both untrained spatial tasks (testing object rotation and perspective taking) and fluid ability tasks; self-reported strategy use was also examined. Our results showed short-term benefits and maintenance effects in the MR and the S + MR groups in terms of their accuracy in both the MR tasks considered (a 3D same/different task, and the Mental Rotations Test). The S + MR group was more accurate at follow-up than at post-test in both MR tasks, and reported using the rotation strategy in association with the tasks; this group was also more accurate at follow-up than at pre-test in the perspective-taking and fluid intelligence tasks. These findings are discussed from the spatial cognition standpoint and with reference to the (rotation) training literature.