Top PDF Frontal networks in adults with autism spectrum disorder

Frontal networks in adults with autism spectrum disorder

Frontal networks in adults with autism spectrum disorder

It has been postulated that autism spectrum disorder is underpinned by an ‘atypical connectivity’ involving higher-order association brain regions. To test this hypothesis in a large cohort of adults with autism spectrum disorder we compared the white matter networks of 61 adult males with autism spectrum disorder and 61 neurotypical controls, using two complementary approaches to diffusion tensor magnetic resonance imaging. First, we applied tract-based spatial statistics, a ‘whole brain’ non-hypothesis driven method, to identify differences in white matter networks in adults with autism spectrum disorder. Following this we used a tract- specific analysis, based on tractography, to carry out a more detailed analysis of individual tracts identified by tract-based spatial statistics. Finally, within the autism spectrum disorder group, we studied the relationship between diffusion measures and autistic symptom severity. Tract-based spatial statistics revealed that autism spectrum disorder was associated with significantly reduced fractional anisotropy in regions that included frontal lobe pathways. Tractography analysis of these specific pathways showed increased mean and perpendicular diffusivity, and reduced number of streamlines in the anterior and long segments of the arcuate fasciculus, cingulum and uncinate—predominantly in the left hemisphere. Abnormalities were also evident in the anterior portions of the corpus callosum connecting left and right frontal lobes. The degree of microstructural alteration of the arcuate and uncinate fasciculi was associated with severity of symptoms in language and social reciprocity in childhood. Our results indicated that autism spectrum disorder is a developmental condition associated with abnormal connectivity of the frontal lobes. Furthermore our findings showed that male adults with autism spectrum disorder have regional differences in brain anatomy, which correlate with specific aspects of autistic symptoms. Overall these results suggest that autism spectrum disorder is a condition linked to aberrant develop- mental trajectories of the frontal networks that persist in adult life.
Show more

17 Read more

Frontal networks in adults with autism spectrum disorder

Frontal networks in adults with autism spectrum disorder

It has been postulated that autism spectrum disorder is underpinned by an ‘atypical connectivity’ involving higher-order association brain regions. To test this hypothesis in a large cohort of adults with autism spectrum disorder we compared the white matter networks of 61 adult males with autism spectrum disorder and 61 neurotypical controls, using two complementary approaches to diffusion tensor magnetic resonance imaging. First, we applied tract-based spatial statistics, a ‘whole brain’ non-hypothesis driven method, to identify differences in white matter networks in adults with autism spectrum disorder. Following this we used a tract- specific analysis, based on tractography, to carry out a more detailed analysis of individual tracts identified by tract-based spatial statistics. Finally, within the autism spectrum disorder group, we studied the relationship between diffusion measures and autistic symptom severity. Tract-based spatial statistics revealed that autism spectrum disorder was associated with significantly reduced fractional anisotropy in regions that included frontal lobe pathways. Tractography analysis of these specific pathways showed increased mean and perpendicular diffusivity, and reduced number of streamlines in the anterior and long segments of the arcuate fasciculus, cingulum and uncinate—predominantly in the left hemisphere. Abnormalities were also evident in the anterior portions of the corpus callosum connecting left and right frontal lobes. The degree of microstructural alteration of the arcuate and uncinate fasciculi was associated with severity of symptoms in language and social reciprocity in childhood. Our results indicated that autism spectrum disorder is a developmental condition associated with abnormal connectivity of the frontal lobes. Furthermore our findings showed that male adults with autism spectrum disorder have regional differences in brain anatomy, which correlate with specific aspects of autistic symptoms. Overall these results suggest that autism spectrum disorder is a condition linked to aberrant develop- mental trajectories of the frontal networks that persist in adult life.
Show more

15 Read more

An eye-movement study of relational memory in adults with Autism Spectrum Disorder

An eye-movement study of relational memory in adults with Autism Spectrum Disorder

Acknowledgments We would like to thank Dr Roy Kessels and Professor Albert Postma for providing information on the paradigm and some of the pictures that were used in this research. We are grate- ful to Professor James Hampton for advice on how to determine the locations in the first pilot study. We thank Anna Lambrechts and André Müller for advice on Matlab, and our gratitude goes to all the participants, who have taken part in this research. This study has been supported by a Doctoral studentship from City, University of London to the first author. A preliminary version of the results reported in this manuscript was presented at the International Meeting for Autism Research (IMFAR; May, 2013) in Donostia/San Sebastian, Spain. The eye-movement data presented here were obtained on a sub-sample of participants that took part in a study that was published elsewhere: Ring et  al. (2015). Object-location memory in adults with autism spectrum disorder. Autism Research, 8(5), 609-619.
Show more

12 Read more

Support for adults with autism spectrum disorder without intellectual impairment: Systematic review

Support for adults with autism spectrum disorder without intellectual impairment: Systematic review

Approximately 1% of the population have autism spectrum disorder (ASD) (Brugha et al., 2011). While many people also have an accompanying intellectual impairment (defined as an IQ less than 70), many have normal or above-normal intelligence; under DSM-5 criteria (American Psychiatric Association 2013) this includes people who were previously diagnosed with Asperger’s syndrome. Data from children suggest that between 45% (Baird et al., 2006) and 68% (Christensen et al., 2016) of those with ASD do not have accompanying intellectual impairment. These figures suggest that this proportion is increasing over time, probably due to changing practices in the diagnosis of ASD. If so, we can expect a substantial increase in the number of adults diagnosed with ASD without
Show more

59 Read more

The experiences and needs of female adults with high functioning autism spectrum disorder

The experiences and needs of female adults with high functioning autism spectrum disorder

There is limited large-scale research into the lived experiences of female adults who have an autism spectrum disorder (ASD) with no co-occurring intellectual disability (ID). Drawing on the findings of an Australia-wide survey, this paper presents self-report data from n=82 women with high functioning ASD with respect to their health, education, employment, social and community activities. Where relevant, comparisons are provided with the male subset of the same study population: however, in the majority of analyses no discernible gender differences emerged. The findings highlight the diverse and complex challenges faced by women with high functioning ASD, including high levels of mental health disorder, unmet support needs in education settings and the workplace, and social exclusion and isolation. Keywords
Show more

17 Read more

Autism spectrum disorder in adults: diagnosis, management, and health services development

Autism spectrum disorder in adults: diagnosis, management, and health services development

Abstract: Autism spectrum disorder (ASD) is a common neurodevelopmental disorder characterized by pervasive difficulties since early childhood across reciprocal social communication and restricted, repetitive interests and behaviors. Although early ASD research focused primarily on children, there is increasing recognition that ASD is a lifelong neurodevelopmental disorder. However, although health and education services for children with ASD are relatively well estab- lished, service provision for adults with ASD is in its infancy. There is a lack of health services research for adults with ASD, including identification of comorbid health difficulties, rigorous treatment trials (pharmacological and psychological), development of new pharmacotherapies, investigation of transition and aging across the lifespan, and consideration of sex differences and the views of people with ASD. This article reviews available evidence regarding the etiology, legislation, diagnosis, management, and service provision for adults with ASD and considers what is needed to support adults with ASD as they age. We conclude that health services research for adults with ASD is urgently warranted. In particular, research is required to better understand the needs of adults with ASD, including health, aging, service development, transition, treatment options across the lifespan, sex, and the views of people with ASD. Additionally, the outcomes of recent international legislative efforts to raise awareness of ASD and service provision for adults with ASD are to be determined. Future research is required to identify high-quality, evidence-based, and cost-effective models of care. Furthermore, future health services research is also required at the beginning and end of adulthood, including improved transition from youth to adult health care and increased understanding of aging and health in older adults with ASD.
Show more

18 Read more

MicroRNA profiling in adults with high-functioning autism spectrum disorder

MicroRNA profiling in adults with high-functioning autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social communication deficits and repetitive behaviors. Owing to the difficulty of clinical diagnosis, ASD without intellectual disability (i.e., high- functioning ASD) is often overlooked. MicroRNAs (miRNAs) have been recently recognized as potential biomarkers of ASD as they are dysregulated in various tissues of individuals with ASD. However, it remains unclear whether miRNA expression is altered in individuals with high-functioning ASD. Here, we investigated the miRNA expression profile in peripheral blood from adults with high-functioning ASD, and age and gender-matched healthy controls. We identified miR-6126 as being robustly down-regulated in ASD and correlated with the severity of social deficits. Enrichment analysis of predicted target genes revealed potential association with neurons, synapses, and oxytocin signaling pathways. Our findings may provide insights regarding the molecular clues for recognizing high- functioning ASD.
Show more

5 Read more

Quality of Life in Emerging Adults with Autism Spectrum Disorder

Quality of Life in Emerging Adults with Autism Spectrum Disorder

different during adolescence than during childhood. Adolescents with ASD have a unique experience, as they must deal with the typical difficulties that accompany bodily changes and peer relationships in adolescence (Brown & Klute, 2003) while at the same time possessing core deficits that make social relationships and communication difficult. The challenges that are associated with adolescence and the impact they have on the transition from school to adulthood for individuals with disabilities are only recently attracting the attention of researchers and professional personnel (Wehman, 2013). The transition from school to post-secondary education and employment is often difficult. Individuals diagnosed with an autism spectrum disorder experience struggles when transitioning to adulthood, especially in the areas of achieving independence and accessing community supports and services (Wehman, Smith, & Schall, 2009). The impact of having an ASD diagnosis and the characteristics that go along with the diagnosis greatly impact young adults’ independence in every aspect of their lives, including independent living, community integration, social relationships, and community networking (Schall, Wehman & McDonough, 2012).
Show more

96 Read more

Psychiatric and physical comorbidity in adults with autism spectrum disorder

Psychiatric and physical comorbidity in adults with autism spectrum disorder

Within the general population, accepted risk factors for attempted and completed suicide include male gender, unmarried, unemployment, low educational attainment, low income, presence of psychiatric illness or chronic physical illness, childhood adversity, vulnerability and stressful life events (Balfe 2010, Crump 2014). High prevalence for each of these factors has been identified among the ASD population. When reporting on 587 adults admitted via the Emergency Department for attempted suicide, Kato et al (2013) identified 7.3% of patients with autism spectrum disorder. They noted that this subgroup of psychiatric admissions were more likely to be younger, single and living alone, with higher rates of comorbid adjustment disorder, requiring longer hospitalisation and to have used more lethal methods (jumping from a height, cutting / stabbing and carbon monoxide poisoning) when attempting suicide. ASD patients were also less likely to attribute their suicide attempt to a stressor occurring in the preceding 24 hours. Takara and Kondo (2014) examined a group of 336 adults with mood disorders following attempted suicide and noted that 11% fulfilled diagnostic criteria for autism spectrum disorder on the SCID-I. They noted agitation, history of suicidal behaviour and high-functioning autism spectrum disorder to be significantly associated with increased rates of suicide attempt. They also confirmed Kato et al’s (2013) finding relating to use of more lethal methods.
Show more

253 Read more

Brief Report: Impaired Temporal Reproduction Performance in Adults with Autism Spectrum Disorder

Brief Report: Impaired Temporal Reproduction Performance in Adults with Autism Spectrum Disorder

Although temporal processing has received little attention in the autism literature, there are a number of reasons to suspect that people with autism spectrum disorder (ASD) may have particular difficulties judging the passage of time. The present study tested a group of 20 high-functioning adults with ASD and 20 matched comparison participants on a temporal reproduction task. The ASD group made reproductions that were significantly further from the base durations than did the comparison group. They were also more variable in their responses. Furthermore the ASD group showed particular difficulties as the base durations increased, tending to underestimate to a much greater degree than the comparison group. These findings support earlier evidence that temporal processing is impaired in ASD.
Show more

30 Read more

Relational Memory Processes in Adults with Autism Spectrum Disorder

Relational Memory Processes in Adults with Autism Spectrum Disorder

Research into memory in Autism Spectrum Disorder (ASD) suggests intact item memory but difficulties in forming relations between items (Bowler, Gaigg & Lind, 2011). This pattern closely resembles that seen in typically developed (TD) older adults thus supporting the ‘ageing analogy’ (Bowler, 2007). In this study we tested memory for items as well as for sequential, spatial and associative relations between items with the same paradigm using abstract shapes in ASD and TD individuals. Participants studied shape triplets on a computer- screen and memory was subsequently tested either for the individual items making up the triplets, the screen-locations, the order or the combinations of items presented at study. We also examined age-related differences in memory across the mid-adult lifespan in both groups. Performance was significantly lower in the ASD group on all 4 tasks but particularly on the relational tasks. When considering order memory and age-related differences across the lifespan (20-62 years), we found a significant decrease in order memory with increasing age for the TD but not the ASD group. Younger ASD individuals performed significantly worse on the order task compared to younger TD but not older TD individuals. Whereas older ASD and older TD individuals performed similarly, suggesting a parallel between the memory performance of ASD individuals and that of older TD adults. Results are in line with evidence of relational memory difficulties in people with ASD (Bowler et al., 2011) and broadly support the ‘ageing analogy’ (Bowler, 2007) of autistic memory.
Show more

32 Read more

Perceptions of Vocational Education Training Specialists and Employers of Adults with Autism Spectrum Disorder

Perceptions of Vocational Education Training Specialists and Employers of Adults with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorders characterized by persistent deficits in social communication and social interaction and restricted, repetitive patterns of behavior, interests, and activities. The world prevalence of ASD was 1 in 132, and 1 in 59 in the United States, continuing to increase annually (CDC, 2018). The total cost for behavior interventions for a single individual with ASD costs $40,000 to $60,000 annually (CDC, 2018). The 2015 annual Disabilities Status Report determined that 35.2% of working age people (age 21-64) with disabilities in the United States were employed, while the U. S. Bureau of Labor Statistics reported 31.0% of working age people (age 21-64) with disabilities in the state of Florida were employed ( Erickson et al . 2016). The increasing annual prevalence of ASD, high unemployment rate, and the inability of VET programs to address marginalization for the young adults with ASD creates an employment gap between the employed and unemployed. There are numerous benefits of employing young adults with ASD within the workplace (i.e. creativity) and personal development (i.e. autonomy, confidence).
Show more

205 Read more

Anxiety and Depression in Adults with Autism Spectrum Disorder: A Systematic Review and Meta-analysis

Anxiety and Depression in Adults with Autism Spectrum Disorder: A Systematic Review and Meta-analysis

The Mood and Anxiety Semi-Structured (MASS) Interview (Charlot et al., 2007) It contains 29 questions relating to the presence of DSM-IV symptom criteria for mood and anxiety disorders and is designed for easy administration to individuals with intellectual disorder. Each symptom item is accompanied with a few behavioural examples, in which administer has to

54 Read more

Abnormal wiring of the connectome in adults with high-functioning autism spectrum disorder

Abnormal wiring of the connectome in adults with high-functioning autism spectrum disorder

In the node-level analyses of the density-weighted net- work, the strength of the right superior temporal pole was significantly lower in subjects with ASD. The right tem- poral pole is associated with emotions and socially rele- vant memories, whereas the left temporal pole is related to semantic memory [59]. Damage to the right temporal pole may induce emotional blunting, inability to be at ease in social company, and reduced ability to recognize fam- ous or family faces [59]. Moreover, patients with temporal variation of frontal temporal dementia with right temporal pole atrophy may become introverted, cold, and lack empathy [59]. In addition, the temporal pole is thought to have an important role in the theory of mind network [59]. Many of these symptoms fit well with the clinical manifestation of Asperger syndrome. All of the node-level differences between the subjects with ASD and controls both in the binary and the density-weighted networks are reported in Additional file 1: Table S1, but the other results are not discussed here as they did not endure the strict Bonferroni correction for multiple comparisons.
Show more

11 Read more

Judgment of Learning Accuracy in High-functioning Adolescents and Adults with Autism Spectrum Disorder

Judgment of Learning Accuracy in High-functioning Adolescents and Adults with Autism Spectrum Disorder

Whatever the explanation for the finding of undimin- ished JOL accuracy in the current study, the finding itself has important implications for educational practice. Judgements of learning are considered to have different functions for everyday learning and control of behaviour/ cognition than feelings of knowing and judgements of confidence. For example, judgments of learning specifi- cally are thought to be involved in guiding allocation of study time and self-paced study, which are determinants of learning success (e.g., Son and Metcalfe 2000). For example, individuals can use judgements of learning to (a) decide whether or not to study particular information (with sufficiently high judgments of learning leading to no study), and (b) decide on the order of priority that infor- mation should be studied in (see e.g., Metcalfe and Kornell 2005; Kornell and Metcalfe 2006). During efficient learn- ing, people adaptively study material they believe they almost know first, then progressively more difficult mate- rial (i.e., studying items with high judgements of learning first, then material with low judgements of learning). Alternatively, learners might first choose to study items they judge as difficult (i.e., items given low judgements of learning; Dunlosky and Hertzog 1997; Thiede and Dun- losky 1999). Either way, efficient learning and decision- making rely to some extent on an individual being able to make relatively accurate judgments of learning. Indeed, JOL accuracy is a specific predictor of learning ability (e.g., Thiede 1999). Given that adults and adolescents with ASD appear as accurate as neurotypical individuals at JOL, it would be useful for teachers to encourage students with ASD to make explicit judgments of learning when trying to learn new material. It may be that adolescents with ASD do not make such judgements spontaneously, as neurotypical adolescents do, and so future research might usefully explore the effect on learning of asking versus not asking adolescents to make such judgements.
Show more

14 Read more

Atypical Neurophysiology Underlying Episodic and Semantic Memory in Adults with Autism Spectrum Disorder

Atypical Neurophysiology Underlying Episodic and Semantic Memory in Adults with Autism Spectrum Disorder

The brain bases of language abnormalities in individuals with ASD have been extensively studied using auditory ERPs (see Bomba & Pang, 2004 for a review). The P300 or P3 ERP, including both P3a (recorded when participants are actively attending and P3b (recorded during passive attention) have been used to investigate language, and auditory processing in children with Asperger’s Disorder (Lepisto, Silokallio, Nieminen-von Wendt, Alku Naatanen & Kujala, 2006), and to investigate how children with ASD orient to unattended changes in their environment (Escera, Alho, Schroger & Winkler, 2000).. The P3a has been found to be diminished in amplitude for adolescents with ASD when elicited by highly attention-catching novel sounds (Courchesne, Kilman, Galambos & Lincoln, 1984), as well as by subtle changes in speech, as opposed to non- speech changes in children with ASD (Lespito, Kujala, Vanhala, Alku, Huotilainen & Naatanen, 2005). Furthermore, the mismatch negativity (an ERP that indexes sound discrimination accuracy), is elicited by a perceptible change in a sequence of repeated sounds (Naatanen, 1992), and studies have shown that in children with ASD, pitch- mismatch negativity is diminished (Seri, Cerquiglini, Pisani & Curatolo, 1999), along with diminished mismatch negativity amplitudes for duration (Lepisto et al., 2005) and consonant changes (Kuhl, Coffey-Corina, Padden & Dawson, 2005). Taken together these results suggest that individuals with ASD have difficulties with sound discrimination..
Show more

52 Read more

Distinctive Rorschach profiles of young adults with schizophrenia and autism spectrum disorder

Distinctive Rorschach profiles of young adults with schizophrenia and autism spectrum disorder

We recruited 20 SZ (12 males: mean ± SD age 24.9 ± 6.5 years; eight females: mean ± SD age 27.8 ± 3.3 years) and ASD (14 males: mean ± SD age 26.2 ± 4.8 years; six females: mean ± SD age 26.2 ± 5.0 years) patients from the outpatient clinics at the Department of Psychiatry, Nara Medical Uni- versity and Kyo Mental Clinic, Nara, Japan. At least two experienced psychiatrists reached consensus concerning DSM-IV-TR, diagnosis of SZ and ASD (autistic disorder, Asperger disorder, or PDD – not otherwise specified) for each subject, based on structured interviews and reviews of patient medical records. The exclusion criteria included neurological disorders, history of traumatic brain injury and electroconvulsive therapy, serious medical conditions, or any psychiatric comorbidity. The patients’ intellectual levels were assessed using the Wechsler adult intelligence scale-third edition. Those who demonstrated a score ,70 on the full- scale IQ were excluded from the present study by a trained psychologist. Sixteen patients with SZ received neuroleptics (daily chlorpromazine [CP] equivalent dose: 459 ± 583 mg CP equivalent), while only two patients with ASD received daily doses of 25 or 550 mg CP equivalent of neuroleptics, respec- tively. Consequently, the SZ group took more CP equivalent mean dosages for antipsychotics than did the ASD group.
Show more

8 Read more

Crowding and visual search in high functioning adults with autism spectrum disorder

Crowding and visual search in high functioning adults with autism spectrum disorder

population. In their study, the authors used high function- ing adults with ages ranging from 20–62 years to see if the higher discrimination ability was related to an inability to perceive differences between similar objects based upon a prototype of the object in question. The hypothesis being that if individuals with high functioning autism do have greater visual discrimination then this would be manifested by a reduction in their ability to categorize an object accord- ing to its prototype because they would perceive differences in every object and assign it to a novel category. The main findings were that these high functioning adults showed no reduction in the perceptual sensitivity based on their ability to categorize the items correctly. 57 The authors concluded
Show more

12 Read more

Metacognition, Metamemory, and Mindreading in High-Functioning Adults With Autism Spectrum Disorder

Metacognition, Metamemory, and Mindreading in High-Functioning Adults With Autism Spectrum Disorder

9 Thus, for several reasons it is important to establish the extent to which individuals with ASD show diminished metacognitive ability. In a seminal paper, Frith and Happé (1999) argued explicitly that individuals with ASD are as impaired at metacognition as they are at mindreading. More recently, Williams (2010) has taken up this idea, citing evidence that individuals with this disorder are as impaired at recognising their own and others’ thought processes (Hurlburt, Happé, & Frith, 1994), emotions (Williams & Happé, 2010a) and specific mental states, such as beliefs and intentions (Williams & Happé, 2010b), as they are at recognising these states in others. Evidence from “self” versions of classic mindreading tasks (e.g., Williams & Happé, 2009), in which participants are asked to report their own previously held (now false) belief, also suggests that individuals with ASD demonstrate diminished awareness of their own beliefs. Each of these findings suggests that
Show more

40 Read more

Motion and pattern cortical potentials in adults with high-functioning autism spectrum disorder

Motion and pattern cortical potentials in adults with high-functioning autism spectrum disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition affecting approximately 1:100 individuals, with a higher prevalence amongst males [1]. Individuals with ASD have difficulties in three core diagnostic domains of: reciprocal social interaction, communication and repetitive behaviours and restricted interests [2]. Whilst, the direct aetiology of ASD remains unclear, several studies indicate a complex genetic origin, which may be influenced by environmental factors such as hormones or inflammation to disrupt neural maturation in the brain, [3-5]. There is some evidence of this in MRIs of individuals with ASD who display an increased white matter bulk and reduced long range connectivity between regions of the brain, most notably laterally, but also from anterior to posterior. The general model is one of local over-
Show more

26 Read more

Show all 10000 documents...