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Gresham FM, Beebe-Frankenberger ME, MacMillan DL. A Selective Review of Treatments for Children with Autism: Description and Methodological Considerations. SCHOOL PSYCHOLOGY REVIEW 2019. [DOI: 10.1080/02796015.1999.12085985] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Viljoen M, Mahdi S, Griessel D, Bölte S, de Vries PJ. Parent/caregiver perspectives of functioning in autism spectrum disorders: A comparative study in Sweden and South Africa. AUTISM : THE INTERNATIONAL JOURNAL OF RESEARCH AND PRACTICE 2019; 23:2112-2130. [PMID: 31044605 DOI: 10.1177/1362361319829868] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Functional outcomes in autism spectrum disorder can be highly variable given the heterogeneous nature of autism spectrum disorder and its interaction with environmental factors. We set out to compare parent/caregiver perceptions of functioning in two divergent countries that participated in the International Classification of Functioning Disability and Health (ICF) Core Set for Autism Spectrum Disorder development study. We focused on the frequency and content of items reported, and hypothesized that environmental factors would most frequently be reported as barriers to functioning in low-resource settings. Using frequency and qualitative content analysis, we compared data from South Africa (n = 22) and Sweden (n = 13). Frequency agreement was seen in three activities and participation categories, and one environmental factor. Obvious frequency differences were observed in one environmental factors category, six body functions categories and three activities and participation categories. Only three ICF categories (immediate family, attention functions, products and technology for personal use) differed in content. Contrary to our hypotheses, few differences in perspectives about environmental factors emerged. The universality of our findings supports the global usefulness of the recently developed ICF Core Sets for Autism Spectrum Disorder. We recommend that more comparative studies on autism spectrum disorder and functioning should be conducted, and that similar comparisons in other disorders where Core Sets have been developed may be valuable.
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Affiliation(s)
| | - Soheil Mahdi
- Karolinska Institutet, Sweden.,Stockholm County Council, Sweden
| | | | - Sven Bölte
- Karolinska Institutet, Sweden.,Stockholm County Council, Sweden.,Curtin University, Western Australia
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Cai J, Hu X, Guo K, Yang P, Situ M, Huang Y. Increased Left Inferior Temporal Gyrus Was Found in Both Low Function Autism and High Function Autism. Front Psychiatry 2018; 9:542. [PMID: 30425664 PMCID: PMC6218606 DOI: 10.3389/fpsyt.2018.00542] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 10/11/2018] [Indexed: 02/05/2023] Open
Abstract
Previous neuroimaging studies of autism spectrum disorder (ASD) have focused on subjects with IQ > 70 or ASD without considering IQ levels. It remains unclear whether differences in brain anatomy in this population are associated with variations in clinical phenotype. In this study, 19 children with low functioning autism (LFA) and 19 children with high functioning autism (HFA) were compared with 27 healthy controls (HC). We found increased gray matter volume (GMV) in the left inferior temporal gyrus in subjects with both HFA and LFA and increased GMV of left middle temporal gyrus BA21 was found only in the LFA group. A significant negative correlation was found between the left inferior temporal gyrus (LITG) and the score of repetitive behavior in the HFA group.
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Affiliation(s)
- Jia Cai
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China
| | - Xiao Hu
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China
| | - Kuifang Guo
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China
| | - Pingyuan Yang
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China
| | - Mingjing Situ
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China
| | - Yi Huang
- Mental Health Center, West China Hospital of Sichuan University, Chengdu, China.,Psychiatric Laboratory, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Brain Research Center, West China Hospital of Sichuan University, Chengdu, China
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A voxel-based morphometry comparison of regional gray matter between fragile X syndrome and autism. Psychiatry Res 2009; 174:138-45. [PMID: 19853418 PMCID: PMC2783567 DOI: 10.1016/j.pscychresns.2009.04.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 03/02/2009] [Accepted: 04/27/2009] [Indexed: 11/21/2022]
Abstract
The phenotypic association between fragile X syndrome (FXS) and autism is well established, but no studies have directly compared whole-brain anatomy between the two disorders. We performed voxel-based morphometry analyses of magnetic resonance imaging (MRI) scans on 10 individuals with FXS, 10 individuals with autism, and 10 healthy comparison subjects to identify volumetric changes in each disorder. Regional gray matter volumes within frontal, parietal, temporal, and cingulate gyri, as well as in the caudate nuclei and cerebellum, were larger in the FXS group relative to the autism group. In addition, volume increases in FXS were observed in frontal gyri and caudate nuclei compared to controls. The autism group exhibited volume increases in frontal and temporal gyri relative to the FXS group, and no volume increases relative to controls. Volumetric deficits relative to controls were observed in regions of the cerebellum for both groups, with additional deficits in parietal and temporal gyri for the FXS group. Our caudate nuclei and frontal gyri results may implicate dysfunction of frontostriatal circuitry in FXS. Cerebellar deficits suggest atypical development of the cerebellum contributing to the phenotype of both disorders, but further imply that unique cerebellar regions contribute to the phenotype of each disorder.
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Systematic genotype-phenotype analysis of autism susceptibility loci implicates additional symptoms to co-occur with autism. Eur J Hum Genet 2009; 18:588-95. [PMID: 19935830 DOI: 10.1038/ejhg.2009.206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Many genetic studies in autism have been performed, resulting in the identification of multiple linkage regions and cytogenetic aberrations, but little unequivocal evidence for the involvement of specific genes exists. By identifying novel symptoms in these patients, enhanced phenotyping of autistic individuals not only improves understanding and diagnosis but also helps to define biologically more homogeneous groups of patients, improving the potential to detect causative genes. Supported by recent copy number variation findings in autism, we hypothesized that for some susceptibility loci, autism resembles a contiguous gene syndrome, caused by aberrations within multiple (contiguous) genes, which jointly increases autism susceptibility. This would result in various different clinical manifestations that might be rather atypical, but that also co-occur with autism. To test this hypothesis, 13 susceptibility loci, identified through genetic linkage and cytogenetic analyses, were systematically analyzed. The Online Mendelian Inheritance in Man database was used to identify syndromes caused by mutations in the genes residing in each of these loci. Subsequent analysis of the symptoms expressed within these disorders allowed us to identify 33 symptoms (significantly more than expected, P=0.037) that were over-represented in previous reports mapping to these loci. Some of these symptoms, including seizures and craniofacial abnormalities, support our hypothesis as they are already known to co-occur with autism. These symptoms, together with ones that have not previously been described to co-occur with autism, might be considered for use as inclusion or exclusion criteria toward defining etiologically more homogeneous groups for molecular genetic studies of autism.
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Rout UK, Dhossche DM. A pathogenetic model of autism involving Purkinje cell loss through anti-GAD antibodies. Med Hypotheses 2008; 71:218-21. [DOI: 10.1016/j.mehy.2007.11.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Accepted: 11/21/2007] [Indexed: 10/22/2022]
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7
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Lepistö T, Kajander M, Vanhala R, Alku P, Huotilainen M, Näätänen R, Kujala T. The perception of invariant speech features in children with autism. Biol Psychol 2007; 77:25-31. [PMID: 17919805 DOI: 10.1016/j.biopsycho.2007.08.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 08/19/2007] [Accepted: 08/24/2007] [Indexed: 11/16/2022]
Abstract
We investigated whether the good pitch-discrimination abilities reported in individuals with autism have adverse effects on their speech perception by compromising their ability to extract invariant phonetic features from speech input. The MMN, a brain response reflecting sound-discrimination processes, was recorded from children with autism and their controls for phoneme-category and pitch changes in speech stimuli under two different conditions: (a) when all the other features of the standard and deviant stimuli were kept constant, and (b) when constant variation with respect to an irrelevant feature was introduced to the standard and deviant stimuli. Children with autism had enhanced MMNs for pitch changes in both conditions, as well as for phoneme-category changes in the constant-feature condition. However, when the phoneme-category changes occurred in phonemes having pitch variation, the MMN enhancement was abolished in autistic children. This suggests that children with autism lose their advantage in phoneme discrimination when the context of the stimuli is speech-like and requires abstracting invariant speech features from varying input.
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Affiliation(s)
- T Lepistö
- Cognitive Brain Research Unit, Department of Psychology, University of Helsinki, P.O. Box 9, Helsinki FIN-00014, Finland.
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Rojas DC, Peterson E, Winterrowd E, Reite ML, Rogers SJ, Tregellas JR. Regional gray matter volumetric changes in autism associated with social and repetitive behavior symptoms. BMC Psychiatry 2006; 6:56. [PMID: 17166273 PMCID: PMC1770914 DOI: 10.1186/1471-244x-6-56] [Citation(s) in RCA: 237] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Accepted: 12/13/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although differences in brain anatomy in autism have been difficult to replicate using manual tracing methods, automated whole brain analyses have begun to find consistent differences in regions of the brain associated with the social cognitive processes that are often impaired in autism. We attempted to replicate these whole brain studies and to correlate regional volume changes with several autism symptom measures. METHODS We performed MRI scans on 24 individuals diagnosed with DSM-IV autistic disorder and compared those to scans from 23 healthy comparison subjects matched on age. All participants were male. Whole brain, voxel-wise analyses of regional gray matter volume were conducted using voxel-based morphometry (VBM). RESULTS Controlling for age and total gray matter volume, the volumes of the medial frontal gyri, left pre-central gyrus, right post-central gyrus, right fusiform gyrus, caudate nuclei and the left hippocampus were larger in the autism group relative to controls. Regions exhibiting smaller volumes in the autism group were observed exclusively in the cerebellum. Significant partial correlations were found between the volumes of the caudate nuclei, multiple frontal and temporal regions, the cerebellum and a measure of repetitive behaviors, controlling for total gray matter volume. Social and communication deficits in autism were also associated with caudate, cerebellar, and precuneus volumes, as well as with frontal and temporal lobe regional volumes. CONCLUSION Gray matter enlargement was observed in areas that have been functionally identified as important in social-cognitive processes, such as the medial frontal gyri, sensorimotor cortex and middle temporal gyrus. Additionally, we have shown that VBM is sensitive to associations between social and repetitive behaviors and regional brain volumes in autism.
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Affiliation(s)
- Donald C Rojas
- Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, 80220, USA
| | - Eric Peterson
- Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, 80220, USA
| | - Erin Winterrowd
- Department of Psychology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Martin L Reite
- Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, 80220, USA
| | - Sally J Rogers
- Department of Psychiatry and M.I.N.D. Institute, University of California at Davis, Sacramento, CA, 95817, USA
| | - Jason R Tregellas
- Department of Psychiatry, University of Colorado Health Sciences Center, Denver, CO, 80220, USA
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Hoeksma MR, Kemner C, Kenemans JL, van Engeland H. Abnormal Selective Attention Normalizes P3 Amplitudes in PDD. J Autism Dev Disord 2006; 36:643-54. [PMID: 16652236 DOI: 10.1007/s10803-006-0102-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
This paper studied whether abnormal P3 amplitudes in PDD are a corollary of abnormalities in ERP components related to selective attention in visual and auditory tasks. Furthermore, this study sought to clarify possible age differences in such abnormalities. Children with PDD showed smaller P3 amplitudes than controls, but no abnormalities in selective attention. Adolescents with PDD showed abnormal selective attention, as reflected by larger auditory Processing Negativity (PN) and visual N2b, but no P3 abnormalities. Dipole localizations revealed that the locations of PN generators in subjects with PDD differed from controls. It was concluded that the abnormalities in selective attention in adolescents with PDD have a normalizing effect on P3, and possibly act as a compensatory process.
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Affiliation(s)
- Marco R Hoeksma
- Department of Psychopharmacology, Faculty of Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584CA, Utrecht, The Netherlands.
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Abstract
Anterior piriform cortex (aPCX) neurons rapidly filter repetitive odor stimuli despite relatively maintained input from mitral cells. This cortical adaptation is correlated with short-term depression of afferent synapses, in vivo. The purpose of this study was to elucidate mechanisms underlying this nonassociative neural plasticity using in vivo and in vitro preparations and to determine its role in cortical odor adaptation. Lateral olfactory tract (LOT)-evoked responses were recorded in rat aPCX coronal slices. Extracellular and intracellular potentials were recorded before and after simulated odor stimulation of the LOT. Results were compared with in vivo intracellular recordings from aPCX layer II/III neurons and field recordings in urethane-anesthetized rats stimulated with odorants. The onset, time course, and extent of LOT synaptic depression during both in vitro electrical and in vivo odorant stimulation methods were similar. Similar to the odor specificity of cortical odor adaptation in vivo, there was no evidence of heterosynaptic depression between independent inputs in vitro. In vitro evidence suggests at least two mechanisms contribute to this activity-dependent synaptic depression: a rapidly recovering presynaptic depression during the initial 10-20 sec of the post-train recovery period and a longer lasting (approximately 120 sec) depression that can be blocked by the metabotropic glutamate receptor (mGluR) II/III antagonist (RS)-alpha-cyclopropyl-4-phosphonophenylglycine (CPPG) and by the beta-adrenergic receptor agonist isoproterenol. Importantly, in line with the in vitro findings, both adaptation of odor responses in the beta (15-35 Hz) spectral range and the associated synaptic depression can also be blocked by intracortical infusion of CPPG in vivo.
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Affiliation(s)
- Aaron R Best
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA.
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Dietz DM, Pletnikov MV. Postnatal weight gain inhibition does not account for neurobehavioral consequences of neonatal Borna disease virus infection. Physiol Behav 2003; 80:359-66. [PMID: 14637236 DOI: 10.1016/j.physbeh.2003.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neonatal Borna disease virus (BDV) infection of the rat's brain produces neurodevelopmental damage similar to some pathological and clinical features of human developmental disorders, e.g., autism and schizophrenia. Since BDV-infected rats exhibited an inhibition of postnatal weight gain, the present study sought to evaluate a contribution of nutritional status to virus-induced neurodevelopmental injury. We compared neuroanatomical, neurochemical, and behavioral alterations following neonatal BDV infection and rearing in the oversized litters in Fischer344 rats on postnatal day (PND) 26. Despite a comparable weight gain inhibition, different patterns of brain pathology, alterations in brain monoamine systems, and behavioral deficits were observed in the BDV-infected rats compared to the malnourished rats. While no appreciable cell injury was noted in the brains of the malnourished rats, a significant loss of Purkinje cells (PC) and early signs of degeneration of the hippocampal dentate gyrus were found in the BDV-infected rats. Both neonatal BDV infection and postnatal malnourishment increased tissue concentrations of serotonin [5-hydroxytryptamine (5-HT)] in the hippocampus. In contrast, increased turnover of 5-HT in the cortex and hippocampus and elevated turnover of dopamine (DA) in the striatum were found in the malnourished rats only, suggesting that different pathogenic mechanisms might underlie monoamine disturbances in virus-infected and malnourished rats. The observed dissimilar neuroanatomical and neurochemical abnormalities might explain the different responses to novelty in the BDV-infected and malnourished rats. Compared to the control rats, the BDV-infected rats exhibited novelty-induced hyperactivity, while no differences in locomotion were noted between the control and malnourished rats. Taken together, the present data indicate that virus-associated inhibition of postnatal weight gain is unlikely to account for the major BDV-associated neurodevelopmental alterations that seem to be due to specific effects of neonatal BDV infection.
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Affiliation(s)
- David M Dietz
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 618, Baltimore, MD 21205, USA
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Pletnikov MV, Rubin SA, Vogel MW, Moran TH, Carbone KM. Effects of genetic background on neonatal Borna disease virus infection-induced neurodevelopmental damage. I. Brain pathology and behavioral deficits. Brain Res 2002; 944:97-107. [PMID: 12106670 DOI: 10.1016/s0006-8993(02)02723-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pathogenic mechanisms of gene-environment interactions determining variability of human neurodevelopmental disorders remain unclear. In the two consecutive papers, we used the neonatal Borna disease virus (BDV) infection rat model of neurodevelopmental damage to evaluate brain pathology, monoamine alterations, behavioral deficits, and responses to pharmacological treatments in two inbred rat strains, Lewis and Fisher344. The first paper reports that despite comparable virus replication and distribution in the brain of both rat strains, neonatal BDV infection produced significantly greater thinning of the neocortex in BDV-infected Fisher344 rats compared to BDV-infected Lewis rats, while no strain-related differences were found in BDV-induced granule cell loss in the dentate gyrus of the hippocampus and cerebellar hypoplasia. Unlike BDV-infected Lewis rats, more severe BDV-induced brain pathology in Fisher344 rats was associated with (1) greater locomotor activity to novelty and (2) impairment of habituation and prepulse inhibition of the acoustic startle response. The present data demonstrate that the same environmental insult can produce differential neuroanatomical and behavioral abnormalities in genetically different inbred rat strains.
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Affiliation(s)
- Mikhail V Pletnikov
- Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Weidenheim KM, Goodman L, Dickson DW, Gillberg C, Råstam M, Rapin I. Etiology and pathophysiology of autistic behavior: clues from two cases with an unusual variant of neuroaxonal dystrophy. J Child Neurol 2001; 16:809-19. [PMID: 11732766 DOI: 10.1177/08830738010160110601] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Two unrelated individuals with autistic behavior had numerous swollen axon terminals (spheroids) located in specific brain regions relevant to their behavioral symptoms. Spheroids are characteristic of neuroaxonal dystrophy, but the clinical profile and anatomic distribution of the lesions in these two patients differed from those of previously described patients with neuroaxonal dystrophy. Spheroids were numerous in the sensory nuclei of the spinal cord and medulla, specific nuclei and the reticular formation of the brainstem tegmentum, hypothalamus, anterior and dorsomedial thalamus, hippocampus, and cingulate and orbitofrontal cortices. Spheroids were sparse in the primary and association cortices and basal ganglia and absent in the hemispheric white matter. Cerebellar atrophy was present in both cases but associated with spheroids in only one case. These cases represent a new variant of neuroaxonal dystrophy in which behavioral symptoms characteristic of autism dominated the clinical picture. Neuroaxonal dystrophy should be included in the list of diseases that may be found in persons with autism.
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Affiliation(s)
- K M Weidenheim
- Department of Pathology (Neuropathology), Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10467, USA.
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Müller RA, Pierce K, Ambrose JB, Allen G, Courchesne E. Atypical patterns of cerebral motor activation in autism: a functional magnetic resonance study. Biol Psychiatry 2001; 49:665-76. [PMID: 11313034 DOI: 10.1016/s0006-3223(00)01004-0] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Early neurodevelopmental pathogenesis in autism potentially affects emerging functional maps, but little imaging evidence is available. METHODS We studied eight male autistic and eight matched normal subjects, using functional magnetic resonance imaging during visually paced finger movement, compared to a control condition (visual stimulation in the absence of motor response). RESULTS Groupwise analyses showed activation in contralateral perirolandic cortex, basal ganglia, and thalamus, bilateral supplementary motor area, and ipsilateral cerebellum for both groups. However, activations were less pronounced in the autism group. Direct group comparisons demonstrated greater activation in perirolandic and supplementary motor areas in the control group and greater activation (or reduced deactivation) in posterior and prefrontal cortices in the autism group. Intraindividual analyses further showed that strongest activations were consistently located along the contralateral central sulcus in control subjects but occurred in locations differing from individual to individual in the autism group. CONCLUSIONS Our findings, though based on a rather small sample, suggest abnormal individual variability of functional maps and less distinct regional activation/deactivation patterns in autism. The observations may relate to known motor impairments in autism and are compatible with the general hypothesis of disturbances of functional differentiation in the autistic cerebrum.
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Affiliation(s)
- R A Müller
- Laboratory for the Neuroscience of Autism, Children's Hospital Research Center, 8110 La Jolla Shores Sr. #200, La Jolla, CA 92037, USA
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Abstract
Recent imaging and clinical studies have challenged the concept that the functional role of the cerebellum is exclusively in the motor domain. We present evidence of slowed covert orienting of visuospatial attention in patients with developmental cerebellar abnormality (patients with autism, a disorder in which at least 90% of all postmortem cases reported to date have Purkinje neuron loss), and in patients with cerebellar damage acquired from tumor or stroke. In spatial cuing tasks, normal control subjects across a wide age range were able to orient attention within 100 msec of an attention-directing cue. Patients with cerebellar damage showed little evidence of having oriented attention after 100 msec but did show the effects of attention orienting after 800-1200 msec. These effects were demonstrated in a task in which results were independent of the motor response. In this task, smaller cerebellar vermal lobules VI-VII (from magnetic resonance imaging) were associated with greater attention-orienting deficits. Although eye movements may also be disrupted in patients with cerebellar damage, abnormal gaze shifting cannot explain the timing and nature of the attention-orienting deficits reported here. These data may be consistent with evidence from animal models that suggest damage to the cerebellum disrupts both the spatial encoding of a location for an attentional shift and the subsequent gaze shift. These data are also consistent with a model of cerebellar function in which the cerebellum supports a broad spectrum of brain systems involved in both nonmotor and motor function.
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