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1.
Dev Psychopathol ; : 1-13, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37990408

RESUMO

Sensory differences and anxiety disorders are highly prevalent in autistic individuals with and without ADHD. Studies have shown that sensory differences and anxiety are associated and that intolerance of uncertainty (IU) plays an important role in this relationship. However, it is unclear as to how different levels of the sensory processing pathway (i.e., perceptual, affective, or behavioral) contribute. Here, we used psychophysics to assess how alterations in tactile perception contribute to questionnaire measures of sensory reactivity, IU, and anxiety. Thirty-eight autistic children (aged 8-12 years; 27 with co-occurring ADHD) were included. Consistent with previous findings, mediation analyses showed that child-reported IU fully mediated an association between parent-reported sensory reactivity and parent-reported anxiety and that anxiety partially mediated an association between sensory reactivity and IU. Of the vibrotactile thresholds, only simultaneous frequency discrimination (SFD) thresholds correlated with sensory reactivity. Interestingly, we found that sensory reactivity fully mediated an association between SFD threshold and anxiety, and between SFD threshold and IU. Taken together, those findings suggest a mechanistic pathway whereby tactile perceptual alterations contribute to sensory reactivity at the affective level, leading in turn to increased IU and anxiety. This stepwise association can inform potential interventions for IU and anxiety in autism.

2.
Assessment ; : 10731911231198205, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694841

RESUMO

Anecdotal evidence has suggested that rater-based measures (e.g., parent report) may have strong across-trait/within-individual covariance that detracts from trait-specific measurement precision; rater measurement-related bias may help explain poor correlation within Autism Spectrum Disorder (ASD) samples between rater-based and performance-based measures of the same trait. We used a multi-trait, multi-method approach to examine method-associated bias within an ASD sample (n = 83). We examined performance/rater-instrument pairs for attention, inhibition, working memory, motor coordination, and core ASD features. Rater-based scores showed an overall greater methodology bias (57% of variance in score explained by method), while performance-based scores showed a weaker methodology bias (22%). The degree of inter-individual variance explained by method alone substantiates an anecdotal concern associated with the use of rater measures in ASD.

3.
Mol Autism ; 14(1): 31, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37635263

RESUMO

BACKGROUND: Differences in responding to sensory stimuli, including sensory hyperreactivity (HYPER), hyporeactivity (HYPO), and sensory seeking (SEEK) have been observed in autistic individuals across sensory modalities, but few studies have examined the structure of these "supra-modal" traits in the autistic population. METHODS: Leveraging a combined sample of 3868 autistic youth drawn from 12 distinct data sources (ages 3-18 years and representing the full range of cognitive ability), the current study used modern psychometric and meta-analytic techniques to interrogate the latent structure and correlates of caregiver-reported HYPER, HYPO, and SEEK within and across sensory modalities. Bifactor statistical indices were used to both evaluate the strength of a "general response pattern" factor for each supra-modal construct and determine the added value of "modality-specific response pattern" scores (e.g., Visual HYPER). Bayesian random-effects integrative data analysis models were used to examine the clinical and demographic correlates of all interpretable HYPER, HYPO, and SEEK (sub)constructs. RESULTS: All modality-specific HYPER subconstructs could be reliably and validly measured, whereas certain modality-specific HYPO and SEEK subconstructs were psychometrically inadequate when measured using existing items. Bifactor analyses supported the validity of a supra-modal HYPER construct (ωH = .800) but not a supra-modal HYPO construct (ωH = .653), and supra-modal SEEK models suggested a more limited version of the construct that excluded some sensory modalities (ωH = .800; 4/7 modalities). Modality-specific subscales demonstrated significant added value for all response patterns. Meta-analytic correlations varied by construct, although sensory features tended to correlate most with other domains of core autism features and co-occurring psychiatric symptoms (with general HYPER and speech HYPO demonstrating the largest numbers of practically significant correlations). LIMITATIONS: Conclusions may not be generalizable beyond the specific pool of items used in the current study, which was limited to caregiver report of observable behaviors and excluded multisensory items that reflect many "real-world" sensory experiences. CONCLUSION: Of the three sensory response patterns, only HYPER demonstrated sufficient evidence for valid interpretation at the supra-modal level, whereas supra-modal HYPO/SEEK constructs demonstrated substantial psychometric limitations. For clinicians and researchers seeking to characterize sensory reactivity in autism, modality-specific response pattern scores may represent viable alternatives that overcome many of these limitations.


Assuntos
Transtorno Autístico , Adolescente , Humanos , Teorema de Bayes , Cognição , Análise de Dados , Fenótipo
4.
J Autism Dev Disord ; 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118644

RESUMO

BACKGROUND: The Wechsler Intelligence Scale for Children (WISC) employs a hierarchical model of general intelligence in which index scores separate out different clinically-relevant aspects of intelligence; the test is designed such that index scores are statistically independent from one another within the normative sample. Whether or not the existing index scores meet the desired psychometric property of being statistically independent within autistic samples is unknown. METHOD: We conducted a factor analysis on WISC fifth edition (WISC-V) (N = 83) and WISC fourth edition (WISC-IV) (N = 131) subtest data in children with autism. We compared the data-driven exploratory factor analysis with the manual-derived index scores, including in a typically developing (TD) WISC-IV cohort (N = 209). RESULTS: The WISC-IV TD cohort showed the expected 1:1 relationship between empirically derived factors and manual-derived index scores. We observed less unique correlations between our data-driven factors and manualized IQ index scores in both ASD samples (WISC-IV and WISC-V). In particular, in both WISC-IV and -V, working memory (WM) influenced index scores in autistic individuals that do not load on WM in the normative sample. CONCLUSIONS: WISC index scores do not show the desired statistical independence within autistic samples, as judged against an empirically-derived exploratory factor analysis. In particular, within the currently used WISC-V version, WM influences multiple index scores.

5.
Autism Res ; 16(6): 1210-1224, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37097835

RESUMO

Assessing cognitive development is critical in clinical research of autism spectrum disorder (ASD). However, collecting cognitive data from clinically administered assessments can add a significant burden to clinical research in ASD due to the substantial cost and time required, and it is often prohibitive in large-scale studies. There is a need for more efficient, but reliable, methods to estimate cognitive functioning for researchers, clinicians, and families. To examine the degree to which caregiver estimates of cognitive level agree with actual measured intelligence/developmental scores and understand factors that may impact that agreement, 1,555 autistic individuals (81.74% male; age 18 months-18 years) were selected from a large cohort (Simons Foundation Powering Autism Research for Knowledge, SPARK). Results suggest that querying parents about recent testing results and developmental diagnoses can provide valid and useful information on cognitive ability. The agreement of parental estimates varied with age, measured cognitive ability, autistic traits, and adaptive skills. In the context of large-scale research efforts, parent-reported cognitive impairment may be a good proxy for categorical IQ range for survey-based studies when specific IQ scores are not available, circumventing the logistical and financial obstacles of obtaining neuropsychological or neurodevelopmental testing.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Masculino , Criança , Lactente , Feminino , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/psicologia , Pais , Inteligência , Cognição
6.
Front Psychol ; 14: 1060525, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910768

RESUMO

We used a large convenience sample (n = 22,223) from the Simons Powering Autism Research (SPARK) dataset to evaluate causal, explanatory theories of core autism symptoms. In particular, the data-items collected supported the testing of theories that posited altered language abilities as cause of social withdrawal, as well as alternative theories that competed with these language theories. Our results using this large dataset converge with the evolution of the field in the decades since these theories were first proposed, namely supporting primary social withdrawal (in some cases of autism) as a cause of altered language development, rather than vice versa. To accomplish the above empiric goals, we used a highly theory-constrained approach, one which differs from current data-driven modeling trends but is coherent with a very recent resurgence in theory-driven psychology. In addition to careful explication and formalization of theoretical accounts, we propose three principles for future work of this type: specification, quantification, and integration. Specification refers to constraining models with pre-existing data, from both outside and within autism research, with more elaborate models and more veridical measures, and with longitudinal data collection. Quantification refers to using continuous measures of both psychological causes and effects, as well as weighted graphs. This approach avoids "universality and uniqueness" tests that hold that a single cognitive difference could be responsible for a heterogeneous and complex behavioral phenotype. Integration of multiple explanatory paths within a single model helps the field examine for multiple contributors to a single behavioral feature or to multiple behavioral features. It also allows integration of explanatory theories across multiple current-day diagnoses and as well as typical development.

7.
Res Sq ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36712092

RESUMO

Background Differences in responding to sensory stimuli, including sensory hyperreactivity (HYPER), hyporeactivity (HYPO), and sensory seeking (SEEK) have been observed in autistic individuals across sensory modalities, but few studies have examined the structure of these "supra-modal" traits in the autistic population. Methods Leveraging a combined sample of 3,868 autistic youth drawn from 12 distinct data sources (ages 3-18 years and representing the full range of cognitive ability), the current study used modern psychometric and meta-analytic techniques to interrogate the latent structure and correlates of caregiver-reported HYPER, HYPO, and SEEK within and across sensory modalities. Bifactor statistical indices were used to both evaluate the strength of a "general response pattern" factor for each supra-modal construct and determine the added value of "modality-specific response pattern" scores (e.g., Visual HYPER). Bayesian random-effects integrative data analysis models were used to examine the clinical and demographic correlates of all interpretable HYPER, HYPO and SEEK (sub)constructs. Results All modality-specific HYPER subconstructs could be reliably and validly measured, whereas certain modality-specific HYPO and SEEK subconstructs were psychometrically inadequate when measured using existing items. Bifactor analyses unambiguously supported the validity of a supra-modal HYPER construct (ω H = .800), whereas a coherent supra-modal HYPO construct was not supported (ω H = .611), and supra-modal SEEK models suggested a more limited version of the construct that excluded some sensory modalities (ω H = .799; 4/7 modalities). Within each sensory construct, modality-specific subscales demonstrated substantial added value beyond the supra-modal score. Meta-analytic correlations varied by construct, although sensory features tended to correlate most strongly with other domains of core autism features and co-occurring psychiatric symptoms. Certain subconstructs within the HYPO and SEEK domains were also associated with lower adaptive behavior scores. Limitations: Conclusions may not be generalizable beyond the specific pool of items used in the current study, which was limited to parent-report of observable behaviors and excluded multisensory items that reflect many "real-world" sensory experiences. Conclusion Psychometric issues may limit the degree to which some measures of supra-modal HYPO/SEEK can be interpreted. Depending on the research question at hand, modality-specific response pattern scores may represent a valid alternative method of characterizing sensory reactivity in autism.

8.
J Autism Dev Disord ; 53(4): 1305-1318, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34859339

RESUMO

Discernment of possible sex-based variations in presentations of autism spectrum disorder (ASD) symptoms is limited by smaller female samples with ASD and confounds with ASD ascertainment. A large national cohort of individuals with autism, SPARK, allowed parent report data to be leveraged to examine whether intrinsic child characteristics and extrinsic factors differentially impact males and females with ASD. Small but consistent sex differences in individuals with ASD emerged related to both intrinsic and extrinsic factors, with different markers for males and females. Language concerns in males may make discernment of ASD more straightforward, while early motor concerns in females may hamper diagnosis as such delays are not identified within traditional ASD diagnostic criteria.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Masculino , Criança , Feminino , Adolescente , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Caracteres Sexuais , Idioma , Fatores Sexuais
9.
J Autism Dev Disord ; 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36272043

RESUMO

Sensory differences are highly prevalent in autistic individuals. However, few studies have compared their presentation between autistic males and autistic females. We used psychophysics to assess and compare tactile perceptual sensitivity between autistic and non-autistic boys and girls aged between 8 and 12 years of age. While there were sex-differences of amplitude discrimination, frequency discrimination and order judgement thresholds, these sex-differences were not autism-specific. Mean RTs and detection thresholds were elevated in autism but were comparable between the sexes. Tactile sensitivity measures that are elevated in autism but are otherwise comparable between autistic males and autistic females suggest the possibility that certain sensory features could be used as sex-indifferent markers of autism. Further investigation with larger and more representative samples should be conducted before any stronger conclusions are made.

10.
Clin Neuropsychol ; 36(5): 960-980, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34473008

RESUMO

A diagnosis of autism spectrum disorder (ASD) provides access to interventions that are important for fostering development and improving quality of life. Thus, the timeliness of a diagnosis should not be limited by social-distancing limitations whenever possible. Despite this, clear guidance for transitioning autism diagnostic services to a telehealth model of care in the era of the COVID-19 pandemic is lacking. At our Institute, we have adapted our approach to ASD evaluation to promote continued access to evaluation services during this unprecedented time. The purpose of this case series is to provide examples of three different approaches to ASD differential diagnostic services via telehealth that we have taken at our Institute.We illustrate our methods and clinical decision-making, based on patient characteristics and referral aims, in providing telehealth diagnostic services and discuss the advantages and limitations of telehealth utilization in the differential diagnosis of ASD.At our Institute, telehealth services have provided an invaluable opportunity to continue to confirm (or rule out) an ASD diagnosis when appropriate to facilitate access to services during this time. Future research examining the utility of telehealth in the differential diagnosis of ASD is imperative given the potential advantages of telehealth services beyond the COVID-19 pandemic for some patients.


Assuntos
Transtorno do Espectro Autista , COVID-19 , Telemedicina , Transtorno do Espectro Autista/diagnóstico , COVID-19/epidemiologia , Humanos , Testes Neuropsicológicos , Pandemias , Qualidade de Vida , Telemedicina/métodos
11.
Clin Neuropsychol ; 36(5): 1069-1093, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34315336

RESUMO

OBJECTIVE: To examine overlap and divergence of symptomatology in Autism Spectrum Disorder (ASD) with and without co-occurring Attention/Deficit Hyperactivity Disorder (ADHD) and/or Anxiety Disorder by age and sex. METHOD: Participants included 25,078 individuals registered in the SPARK cohort, age 6-18 years. SPARK participation includes online consent and registration, as well as parent-reported ASD, ADHD, and Anxiety Disorder diagnoses, developmental, medical, and intervention history, and standardized rating scales. Individuals with ASD, ASD + ADHD, ASD + Anxiety, or ASD + ADHD + Anxiety were compared on measures assessing social communication, restricted and repetitive behaviors (RRBs), and motor functioning, and differences between male and female profiles were examined. RESULTS: Significant differences in symptom presentation between females/males, school-age/adolescent individuals, and by co-occurring conditions (ASD/ADHD/Anxiety) are apparent, and the impact of co-occurring conditions differed by age and sex. Most notably, school-age femaleswith ASD without co-occurring conditions present with significantly fewer concerns about social communication skills and have better motor skills, but have more prominent RRBs as compared to same-aged males with ASD alone; co-occurring conditions were associated with increased social communication problems and motor concerns, most consistently for school-age females. CONCLUSIONS: School-age females with ASD are at highest risk for underestimation of autism-related symptoms, including underestimation of symptoms beyond core ASD features (motor skills). Further, across ages, particular consideration should be given when probing for social communication symptoms, RRBs, and motor skills in females with ASD alone, as well as with co-occurring ADHD and/or Anxiety. For females with co-occurring symptoms and conditions, use of symptom-specific measures in lieu of omnibus measures should be considered.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Autístico , Adolescente , Transtornos de Ansiedade/complicações , Transtornos de Ansiedade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos
12.
Transl Psychiatry ; 11(1): 411, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326312

RESUMO

Individuals on the autism spectrum are often reported as being hyper- and/or hyporeactive to sensory input. These sensory symptoms were one of the key observations that led to the development of the altered excitation-inhibition (E-I) model of autism, which posits that an increase ratio of excitatory to inhibitory signaling may explain certain phenotypical expressions of autism spectrum disorders (ASD). While there has been strong support for the altered E-I model of autism, much of the evidence has come from animal models. With regard to in-vivo human studies, evidence for altered E-I balance in ASD come from studies adopting magnetic resonance spectroscopy (MRS). Spectral-edited MRS can be used to provide measures of the levels of GABA + (GABA + macromolecules) and Glx (glutamate + glutamine) in specific brain regions as proxy markers of inhibition and excitation respectively. In the current study, we found region-specific elevations of Glx in the primary sensorimotor cortex (SM1) in ASD. There were no group differences of GABA+ in either the SM1 or thalamus. Higher levels of Glx were associated with more parent reported difficulties of sensory hyper- and hyporeactivity, as well as reduced feed-forward inhibition during tactile perception in children with ASD. Critically, the finding of elevated Glx provides strong empirical support for increased excitation in ASD. Our results also provide a clear link between Glx and the sensory symptoms of ASD at both behavioral and perceptual levels.


Assuntos
Transtorno do Espectro Autista , Glutamina , Criança , Ácido Glutâmico , Humanos , Espectroscopia de Ressonância Magnética , Ácido gama-Aminobutírico
13.
Arch Clin Neuropsychol ; 34(8): 1418-1424, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30608513

RESUMO

OBJECTIVE: A number of studies have documented the benefits of neuropsychological evaluation as a tool for understanding brain-behavior relationships in various childhood disorders; however, little is known about the process by which children are referred for neuropsychological evaluation. From a systems perspective, it is important to understand whether there are identifiable referral patterns, and if so, how being aware of such patterns could shape the behavior of providers making those referrals. We aim to examine child characteristics that influence referral for neuropsychological evaluation. METHODS: Retrospective chart review of 773 children who received neuropsychological evaluation and were diagnosed with autism, attention-deficit/hyperactivity disorder, and/or anxiety was completed. Children were divided into groups based on referral source (professional or caregiver) and compared on demographic, behavioral, and medical characteristics. RESULTS: Overall, professionals were more likely than caregivers to refer children for neuropsychological evaluation. Though standardized measures suggested children referred by professionals and caregivers were similar, their clinical presentation appears to be different (i.e., those referred by professionals had more comorbidities and were more likely to be prescribed psychotropic medication than those referred by caregivers). Also, children with public insurance were more likely to be referred by a professional than by their caregiver. CONCLUSIONS: Findings highlight the important role of professionals in identifying "at-risk" children and supporting families through the process of receiving further evaluation when indicated. This information can be used to create a more efficient system for evaluating children and developing treatment plans, providing neuropsychologists with direct information to share with referral sources.


Assuntos
Testes Neuropsicológicos , Encaminhamento e Consulta/estatística & dados numéricos , Fatores Socioeconômicos , Adolescente , Transtornos de Ansiedade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno Autístico/psicologia , Cuidadores , Criança , Pré-Escolar , Comorbidade , Demografia , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Seguro Saúde/estatística & dados numéricos , Masculino , Psicotrópicos/uso terapêutico , Estudos Retrospectivos , Adulto Jovem
14.
Dev Cogn Neurosci ; 29: 140-150, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28089657

RESUMO

Sensory processing abnormalities are among the most common behavioral phenotypes seen in autism spectrum disorder (ASD), typically characterized by either over- or under-responsiveness to stimulation. In this review, we focus on tactile processing dysfunction in ASD. We firstly review clinical studies wherein sensitivity to tactile stimuli has traditionally been assessed by self-, parent- and experimenter-reports. We also discuss recent investigations using psychophysical paradigms that gauge individual tactile thresholds. These more experimentally rigorous studies allow for more objective assessments of tactile abnormalities in ASD. However, little is understood about the neurobiological mechanisms underlying these abnormalities, or the link between tactile abnormalities and ASD symptoms. Neurobiological research that has been conducted has pointed toward dysfunction in the excitation/inhibition balance of the central nervous system of those with ASD. This review covers recent efforts that have investigated tactile dysfunction in ASD from clinical and behavioral perspectives, and some of the efforts to link these to neurobiology. On the whole, findings are inconsistent, which can be ascribed to the subjectivity of clinical assessments, the heterogeneity of ASD cohorts, and the diversity of tactile sensitivity measures. Future endeavors into understanding tactile processing differences in ASD will greatly benefit from controlled experiments driven by neurobiological hypotheses.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Tato , Animais , Humanos
15.
Autism Res ; 10(4): 608-619, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27611990

RESUMO

BACKGROUND: Abnormal responses to tactile stimuli are a common feature of autism spectrum disorder (ASD). Several lines of evidence suggest that GABAergic function, which has a crucial role in tactile processing, is altered in ASD. In this study, we determine whether in vivo GABA levels are altered in children with ASD, and whether alterations in GABA levels are associated with abnormal tactile function in these children. METHODS: GABA-edited magnetic resonance spectroscopy was acquired in 37 children with Autism and 35 typically developing children (TDC) from voxels over primary sensorimotor and occipital cortices. Children performed tactile tasks previously shown to be altered in ASD, linked to inhibitory mechanisms. Detection threshold was measured with- and without the presence of a slowly increasing sub-threshold stimulus. Amplitude discrimination was measured with- and without the presence of an adapting stimulus, and frequency discrimination was measured. RESULTS: Sensorimotor GABA levels were significantly reduced in children with autism compared to healthy controls. Occipital GABA levels were normal. Sensorimotor GABA levels correlated with dynamic detection threshold as well as with the effect of sub-threshold stimulation. Sensorimotor GABA levels also correlated with amplitude discrimination after adaptation (an effect absent in autism) and frequency discrimination in controls, but not in children with autism. CONCLUSIONS: GABA levels correlate with behavioral measures of inhibition. Children with autism have reduced GABA, associated with abnormalities in tactile performance. We show here that altered in vivo GABA levels might predict abnormal tactile information processing in ASD and that the GABA system may be a future target for therapies. Autism Res 2016. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Lobo Occipital/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Percepção do Tato/fisiologia , Ácido gama-Aminobutírico/metabolismo , Transtorno do Espectro Autista/diagnóstico , Criança , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Inibição Neural/fisiologia , Valores de Referência , Estatística como Assunto
16.
J Autism Dev Disord ; 46(10): 3232-41, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27448580

RESUMO

Sensory processing abnormalities in autism have largely been described by parent report. This study used a multi-method (parent-report and measurement), multi-trait (tactile sensitivity and attention) design to evaluate somatosensory processing in ASD. Results showed multiple significant within-method (e.g., parent report of different traits)/cross-trait (e.g., attention and tactile sensitivity) correlations, suggesting that parent-reported tactile sensory dysfunction and performance-based tactile sensitivity describe different behavioral phenomena. Additionally, both parent-reported tactile functioning and performance-based tactile sensitivity measures were significantly associated with measures of attention. Findings suggest that sensory (tactile) processing abnormalities in ASD are multifaceted, and may partially reflect a more global deficit in behavioral regulation (including attention). Challenges of relying solely on parent-report to describe sensory difficulties faced by children/families with ASD are also highlighted.


Assuntos
Atenção/fisiologia , Transtorno do Espectro Autista/fisiopatologia , Desempenho Psicomotor/fisiologia , Tato/fisiologia , Adolescente , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/psicologia , Criança , Humanos , Masculino , Tempo de Reação/fisiologia
18.
J Dev Behav Pediatr ; 35(9): 561-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25211371

RESUMO

OBJECTIVE: This study sought to identify factors that may be associated with delays in autism spectrum disorder (ASD) diagnosis, including birth cohort, sociodemographic characteristics, and clinical features. METHODS: Participants included 1716 children and adolescents with ASD enrolled in the Autism Speaks Autism Treatment Network (AS-ATN) between the years 2008 and 2011. Data were collected at enrollment using AS-ATN parent- and clinician-report forms and standardized measures of I.Q., ASD symptoms, adaptive function, and psychiatric symptoms. RESULTS: Age at first ASD diagnosis was positively correlated with current age, suggesting a birth cohort effect. Sociodemographic and clinical features were also associated with age at diagnosis, even after controlling for current age. Hierarchical linear regression results showed that older current age, lower socioeconomic status (SES), higher I.Q. score, and lower levels of autism symptoms were associated with later age at initial diagnosis. There was also a significant interaction between current age and I.Q., with higher functioning children being diagnosed at younger ages than in previous years. CONCLUSIONS: Early diagnosis of ASD is critically important for improving access to interventions; however, many children experience diagnostic delays. In this sample, children from the most recent birth cohorts were diagnosed earlier, suggesting that early signs of ASD are being increasingly recognized. However, socioeconomic barriers to diagnosis still seem to exist. Children with less severe ASD symptoms and with higher I.Q. are also diagnosed at later ages. Efforts are still needed to reduce diagnostic disparities for families of low SES and to improve early recognition of more subtle symptoms.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Inteligência/fisiologia , Índice de Gravidade de Doença , Classe Social , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Tempo
19.
J Neurophysiol ; 111(9): 1803-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24523518

RESUMO

Impaired responses to tactile stimulation are a commonly reported symptom among children with autism spectrum disorder (ASD). Furthermore, impairments in filtering or habituation to tactile input have been described in ASD. This study measured different aspects of tactile processing to investigate atypical touch sensitivity in children with ASD, methodology that has not been previously used in this population. Sixty-seven typically developing children (TDC) and 32 children with ASD (ages 8-12) completed vibrotactile tasks assessing: reaction time (RT); static and dynamic detection threshold (DT); amplitude discrimination with and without single-site adaptation; frequency discrimination; and temporal order judgment (TOJ) with and without concurrent stimulation. Children with ASD showed raised static detection thresholds and an absence of the effect of a dynamically increasing subthreshold stimulus on static detection threshold. Children with ASD also showed poorer amplitude discrimination than TDC, as well as decreased adaptation. There were no significant differences in frequency discrimination or TOJ performance between the groups. Differences in the effect of dynamic stimulation on detection threshold suggest impaired feed-forward inhibition in autism, which may be linked to poor sensory filtering. Increased baseline amplitude discrimination thresholds in ASD suggest that lateral inhibitory connections are weaker in ASD, and an absence of the effect of adaptation suggests impaired modulation of lateral inhibitory connections in ASD, which may relate to aberrant habituation. These results suggest a functional deficit in the somatosensory inhibitory system in autism. Understanding the specific mechanisms underlying sensory symptoms in autism may allow for more specific therapeutic or drug targeting in the near future.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Percepção do Tato , Tato , Adaptação Fisiológica , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Limiar Sensorial
20.
J Neurosci Methods ; 218(1): 39-47, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23660524

RESUMO

The cortical dynamics of somatosensory processing can be investigated using vibrotactile psychophysics. It has been suggested that different vibrotactile paradigms target different cortical mechanisms, and a number of recent studies have established links between somatosensory cortical function and measurable aspects of behavior. The relationship between cortical mechanisms and sensory function is particularly relevant with respect to developmental disorders in which altered inhibitory processing has been postulated, such as in ASD and ADHD. In this study, a vibrotactile battery consisting of nine tasks (incorporating reaction time, detection threshold, and amplitude- and frequency discrimination) was applied to a cohort of healthy adults and a cohort of typically developing children to assess the feasibility of such a vibrotactile battery in both cohorts, and the performance between children and adults was compared. These results showed that children and adults were both able to perform these tasks with a similar performance, although the children were slightly less sensitive in frequency discrimination. Performance within different task-groups clustered together in adults, providing further evidence that these tasks tap into different cortical mechanisms, which is also discussed. This clustering was not observed in children, which may be potentially indicative of development and a greater variability. In conclusion, in this study, we showed that both children and adults were able to perform an extensive vibrotactile battery, and we showed the feasibility of applying this battery to other (e.g., neurodevelopmental) cohorts to probe different cortical mechanisms.


Assuntos
Discriminação Psicológica/fisiologia , Testes Neuropsicológicos , Estimulação Física/métodos , Psicofísica/métodos , Córtex Somatossensorial/fisiologia , Adulto , Criança , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Percepção do Tato/fisiologia , Vibração
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