1. Burnett HG, Jellema T. {{(Re-)conceptualisation in Asperger’s Syndrome and Typical Individuals with Varying Degrees of Autistic-like Traits}}. {J Autism Dev Disord}. 2012.
The abilities to form new concepts from scratch (conceptualisation), and to flexibly switch from one concept to another (re-conceptualisation), were investigated in adults with Asperger’s Syndrome and in typically-developed adults with low and high autism spectrum quotients. In consecutively presented morphs, containing increasing percentages of animate or inanimate objects, the emerging objects had to be identified. The abilities to conceptualise and reconceptualise became increasingly impaired with increasing autistic(-like) traits. Across both tasks, all groups recognised animate objects quicker than inanimate objects. However, this ‘animate advantage’ was differently affected by the two tasks. In the Reconceptualisation task, the ‘animate advantage’ gradually disappeared with increasing autistic(-like) traits, whereas in the Conceptualisation task it remained present.
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2. Chebuhar A, McCarthy AM, Bosch J, Baker S. {{Using picture schedules in medical settings for patients with an autism spectrum disorder}}. {J Pediatr Nurs}. 2012.
Autism is a neurobiological disorder that compromises ability to communicate and can be accompanied by anxiety, particularly for those in unfamiliar settings with unknown people. To improve communication, children with autism often relate well to pictures; however the literature describes no studies of picture schedules for patients with autism in medical settings. Our pilot project demonstrates how picture schedules for medical settings can relieve anxiety in children with autism and suggests that this approach should be employed as an innovative way to interact with patients with autism.
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3. Fourie CL, Theron LC. {{Resilience in the Face of Fragile X Syndrome}}. {Qual Health Res}. 2012.
In this article, we communicate transformative findings from a case study on the resilience of a young woman with fragile X syndrome (FXS), a genetic condition involving mental impairment and physical, emotional, and behavioral challenges. We explored the resilience of « Lucy, » a spirited 16-year-old North American, using informal interviews with her, formal interviews with significant adults in her life, and observations (visual and anecdotal) over 20 months. In reporting the information-rich case of Lucy, well supported by her ecology to rise above full-mutation FXS, we encourage a positive perspective of living with FXS. Although we recognize the limitations of a single case study, our findings offer tentative, process-oriented insights into resilience in contexts of genetic disability, previously unreported in conjunction with FXS. We concluded that the processes informing Lucy’s resilience were partly her responsibility and partly her social ecology’s, and comprised intrapersonal agency, unconditional positive acceptance and belonging, and support toward mastery.
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4. Srivastava DP, Woolfrey KM, Jones KA, Anderson CT, Smith KR, Russell TA, Lee H, Yasvoina MV, Wokosin DL, Ozdinler PH, Shepherd GM, Penzes P. {{An autism-associated variant of epac2 reveals a role for ras/epac2 signaling in controlling Basal dendrite maintenance in mice}}. {PLoS Biol}. 2012; 10(6): e1001350.
The architecture of dendritic arbors determines circuit connectivity, receptive fields, and computational properties of neurons, and dendritic structure is impaired in several psychiatric disorders. While apical and basal dendritic compartments of pyramidal neurons are functionally specialized and differentially regulated, little is known about mechanisms that selectively maintain basal dendrites. Here we identified a role for the Ras/Epac2 pathway in maintaining basal dendrite complexity of cortical neurons. Epac2 is a guanine nucleotide exchange factor (GEF) for the Ras-like small GTPase Rap, and it is highly enriched in the adult mouse brain. We found that in vivo Epac2 knockdown in layer 2/3 cortical neurons via in utero electroporation reduced basal dendritic architecture, and that Epac2 knockdown in mature cortical neurons in vitro mimicked this effect. Overexpression of an Epac2 rare coding variant, found in human subjects diagnosed with autism, also impaired basal dendritic morphology. This mutation disrupted Epac2’s interaction with Ras, and inhibition of Ras selectively interfered with basal dendrite maintenance. Finally, we observed that components of the Ras/Epac2/Rap pathway exhibited differential abundance in the basal versus apical dendritic compartments. These findings define a role for Epac2 in enabling crosstalk between Ras and Rap signaling in maintaining basal dendrite complexity, and exemplify how rare coding variants, in addition to their disease relevance, can provide insight into cellular mechanisms relevant for brain connectivity.
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5. Tierney AL, Gabard-Durnam L, Vogel-Farley V, Tager-Flusberg H, Nelson CA. {{Developmental trajectories of resting EEG power: an endophenotype of autism spectrum disorder}}. {PLoS One}. 2012; 7(6): e39127.
Current research suggests that autism spectrum disorder (ASD) is characterized by asynchronous neural oscillations. However, it is unclear whether changes in neural oscillations represent an index of the disorder or are shared more broadly among both affected and unaffected family members. Additionally, it remains unclear how early these differences emerge in development and whether they remain constant or change over time. In this study we examined developmental trajectories in spectral power in infants at high- or low-risk for ASD. Spectral power was extracted from resting EEG recorded over frontal regions of the scalp when infants were 6, 9, 12, 18 and 24 months of age. We used multilevel modeling to assess change over time between risk groups in the delta, theta, low alpha, high alpha, beta, and gamma frequency bands. The results indicated that across all bands, spectral power was lower in high-risk infants as compared to low-risk infants at 6-months of age. Furthermore high-risk infants showed different trajectories of change in spectral power in the subsequent developmental window indicating that not only are the patterns of change different, but that group differences are dynamic within the first two years of life. These findings remained the same after removing data from a subset of participants who displayed ASD related behaviors at 24 or 36 months. These differences in the nature of the trajectories of EEG power represent important endophenotypes of ASD.
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6. Watanabe T, Yahata N, Abe O, Kuwabara H, Inoue H, Takano Y, Iwashiro N, Natsubori T, Aoki Y, Takao H, Sasaki H, Gonoi W, Murakami M, Katsura M, Kunimatsu A, Kawakubo Y, Matsuzaki H, Tsuchiya KJ, Kato N, Kano Y, Miyashita Y, Kasai K, Yamasue H. {{Diminished Medial Prefrontal Activity behind Autistic Social Judgments of Incongruent Information}}. {PLoS One}. 2012; 7(6): e39561.
Individuals with autism spectrum disorders (ASD) tend to make inadequate social judgments, particularly when the nonverbal and verbal emotional expressions of other people are incongruent. Although previous behavioral studies have suggested that ASD individuals have difficulty in using nonverbal cues when presented with incongruent verbal-nonverbal information, the neural mechanisms underlying this symptom of ASD remain unclear. In the present functional magnetic resonance imaging study, we compared brain activity in 15 non-medicated adult males with high-functioning ASD to that of 17 age-, parental-background-, socioeconomic-, and intelligence-quotient-matched typically-developed (TD) male participants. Brain activity was measured while each participant made friend or foe judgments of realistic movies in which professional actors spoke with conflicting nonverbal facial expressions and voice prosody. We found that the ASD group made significantly less judgments primarily based on the nonverbal information than the TD group, and they exhibited significantly less brain activity in the right inferior frontal gyrus, bilateral anterior insula, anterior cingulate cortex/ventral medial prefrontal cortex (ACC/vmPFC), and dorsal medial prefrontal cortex (dmPFC) than the TD group. Among these five regions, the ACC/vmPFC and dmPFC were most involved in nonverbal-information-biased judgments in the TD group. Furthermore, the degree of decrease of the brain activity in these two brain regions predicted the severity of autistic communication deficits. The findings indicate that diminished activity in the ACC/vmPFC and dmPFC underlies the impaired abilities of individuals with ASD to use nonverbal content when making judgments regarding other people based on incongruent social information.
