1. Amirault M, Etchegoyhen K, Delord S, Mendizabal S, Kraushaar C, Hesling I, Allard M, Bouvard M, Mayo W. {{Alteration of Attentional Blink in High Functioning Autism: A Pilot Study}}.{ J Autism Dev Disord};2009 (Jul 28)
Autism is characterized by deficits in attention. However, no study has investigated the dynamics of attentional processes in autistic patients yet. The attentional blink (AB) paradigm provides information about the temporal dynamics of attention in particular about the allocation and the duration of an attentional episode. We compared 11 high functioning autistic patients with 15 control participants on a classical AB task. Autistic patients exhibited a deficit in rapidly allocated attentional resources. Further investigations such as coupling AB evaluation with neuroimaging data and/or increasing the size of groups, would allow for investigating the neurobiological substrates of these AB alterations in autistic patients.
2. Congiu S, Schlottmann A, Ray E. {{Unimpaired Perception of Social and Physical Causality, but Impaired Perception of Animacy in High Functioning Children with Autism}}. {J Autism Dev Disord};2009 (Jul 28)
We investigated perception of social and physical causality and animacy in simple motion events, for high-functioning children with autism (CA = 13, VMA = 9.6). Children matched 14 different animations to pictures showing physical, social or non-causality. In contrast to previous work, children with autism performed at a high level similar to VMA-matched controls, recognizing physical causality in launch and social causality in reaction events. The launch deficit previously found in younger children with autism, possibly related to attentional/verbal difficulties, is apparently overcome with age. Some events involved squares moving non-rigidly, like animals. Children with autism had difficulties recognizing this, extending the biological motion literature. However, animacy prompts amplified their attributions of social causality. Thus children with autism may overcome their animacy perception deficit strategically.
3. Farrugia D. {{Exploring stigma: medical knowledge and the stigmatisation of parents of children diagnosed with autism spectrum disorder}}. {Sociol Health Illn};2009 (Jul 29)
This paper analyses 12 parent interviews to investigate the stigmatisation of parents of children diagnosed with an autism spectrum disorder. Drawing on poststructural accounts of the relationship between knowledge and subjectivity, the stigma concept is critically interrogated in order to address previous individualistic constructions of stigmatisation and to place stigma within the power dynamics of social control. The results of the study indicate that a child’s diagnosis with an autism spectrum disorder (ASD) is critical for parents to resist stigmatisation. Parents experienced considerable enacted stigma, but successfully resisted felt stigma by deploying medical knowledge to articulate unspoiled subject positions. The institutionalisation of medical knowledge within the autism community was critical to this process. Resistance to enacted stigma was successful to the degree that medical constructions of deviance deployed by parents were accepted by others, notably those in power within institutions. It is concluded that poststructural accounts of subjectivity and social control provide a useful way of conceptualising stigmatisation. An acceptance of the painful nature of stigma as lived experience co-exists with an emphasis on the constantly negotiated nature of embodied subjectivity as a contingent social process to illustrate the conditions for active resistance to stigmatisation.
4. Jellema T, Lorteije J, van Rijn S, van T’ Wout M, de Haan E, van Engeland H, Kemner C. {{Involuntary interpretation of social cues is compromised in autism spectrum disorders}}. {Autism Res};2009 (Jul 29)
A new social distance judgment task was used to measure quantitatively the extent to which social cues are immediately and involuntary interpreted by typically developing (TD) individuals and by individuals with autism spectrum disorders (ASD). The task thus tapped into the ability to involuntary « pick up » the meaning of social cues. The cues tested were social attention and implied biological motion. Task performance of the ASD and TD groups was similarly affected by a perceptual low-level illusion induced by physical characteristics of the stimuli. In contrast, a high-level illusion induced by the implications of the social cues affected only the TD individuals; the ASD individuals remained unaffected (causing them to perform superior to TD controls). The results indicate that despite intact perceptual processing, the immediate involuntary interpretation of social cues can be compromised. We propose that this type of social cue understanding is a distinct process that should be differentiated from reflective social cue understanding and is specifically compromised in ASD. We discuss evidence for an underpinning neural substrate.
5. Jones TB, Bandettini PA, Kenworthy L, Case LK, Milleville SC, Martin A, Birn RM. {{Sources of group differences in functional connectivity: An investigation applied to autism spectrum disorder}}. {Neuroimage};2009 (Jul 29)
An increasing number of fMRI studies are using the correlation of low-frequency fluctuations between brain regions, believed to reflect synchronized variations in neuronal activity, to infer « functional connectivity ». In studies of autism spectrum disorder (ASD), decreases in this measure of connectivity have been found by focusing on the response to task modulation, by using only the rest periods, or by analyzing purely resting-state data. This difference in connectivity, however, could result from a number of different mechanisms – differences in noise, task-related fluctuations, task performance, or spontaneous neuronal activity. In this study, we investigate the difference in functional connectivity between adolescents with high-functioning ASD and typically developing control subjects by examining the residual fluctuations occurring on top of the fMRI response to an overt verbal fluency task. We find decreased correlations of these residuals (a decreased « connectivity ») in ASD subjects. Furthermore, we find that this decrease was not due to task-related effects, block-to-block variations in task performance, or increased noise, and the difference was greatest when primarily rest periods are considered. These findings suggest that the estimate of disrupted functional connectivity in ASD is likely driven by differences in task-unrelated neuronal fluctuations.
6. Oberman LM, Winkielman P, Ramachandran VS. {{Slow echo: facial EMG evidence for the delay of spontaneous, but not voluntary, emotional mimicry in children with autism spectrum disorders}}. {Dev Sci};2009 (Jul);12(4):510-520.
Spontaneous mimicry, including that of emotional facial expressions, is important for socio-emotional skills such as empathy and communication. Those skills are often impacted in autism spectrum disorders (ASD). Successful mimicry requires not only the activation of the response, but also its appropriate speed. Yet, previous studies examined ASD differences in only response magnitude. The current study investigated timing and magnitude of spontaneous and voluntary mimicry in ASD children and matched controls using facial electromyography (EMG). First, participants viewed and recognized happy, sad, fear, anger, disgust and neutral expressions presented at different durations. Later, participants voluntarily mimicked the expressions. There were no group differences on emotion recognition and amplitude of expression-appropriate EMG activity. However, ASD participants’ spontaneous, but not voluntary, mimicry activity was delayed by about 160 ms. This delay occurred across different expressions and presentation durations. We relate these findings to the literature on mirroring and temporal dynamics of social interaction.
7. Russo N, Nicol T, Trommer B, Zecker S, Kraus N. {{Brainstem transcription of speech is disrupted in children with autism spectrum disorders}}. {Dev Sci};2009 (Jul);12(4):557-567.
Language impairment is a hallmark of autism spectrum disorders (ASD). The origin of the deficit is poorly understood although deficiencies in auditory processing have been detected in both perception and cortical encoding of speech sounds. Little is known about the processing and transcription of speech sounds at earlier (brainstem) levels or about how background noise may impact this transcription process. Unlike cortical encoding of sounds, brainstem representation preserves stimulus features with a degree of fidelity that enables a direct link between acoustic components of the speech syllable (e.g. onsets) to specific aspects of neural encoding (e.g. waves V and A). We measured brainstem responses to the syllable /da/, in quiet and background noise, in children with and without ASD. Children with ASD exhibited deficits in both the neural synchrony (timing) and phase locking (frequency encoding) of speech sounds, despite normal click-evoked brainstem responses. They also exhibited reduced magnitude and fidelity of speech-evoked responses and inordinate degradation of responses by background noise in comparison to typically developing controls. Neural synchrony in noise was significantly related to measures of core and receptive language ability. These data support the idea that abnormalities in the brainstem processing of speech contribute to the language impairment in ASD. Because it is both passively elicited and malleable, the speech-evoked brainstem response may serve as a clinical tool to assess auditory processing as well as the effects of auditory training in the ASD population.
8. Shumway S, Wetherby AM. {{Communicative Acts of Children with Autism Spectrum Disorders in the Second Year of Life}}. {J Speech Lang Hear Res};2009 (Jul 27)
PURPOSE: This study examined the communicative profiles of children with autism spectrum disorders (ASD) in the second year of life. METHOD: Communicative acts were examined in 125 children 18 to 24 months of age: 50 later diagnosed with ASD; 25 with developmental delays (DD); and 50 with typical development (TD). Precise measures of rate, functions, and means of communication were obtained through systematic observation of videotaped Behavior Samples from the Communication and Symbolic Behavior Scales Developmental Profile (Wetherby & Prizant, 2002). RESULTS: Children with ASD communicated at a significantly lower rate than children with DD and TD. The ASD group used a significantly lower proportion of acts for joint attention and a significantly lower proportion of deictic gestures with a reliance on more primitive gestures compared to DD and TD. Children with ASD who did communicate for joint attention were as likely as other children to coordinate vocalizations, eye gaze, and gestures. Rate of communicative acts and joint attention were the strongest predictors of verbal outcome at age 3. CONCLUSIONS: By 18 to 24 months of age, children later diagnosed with ASD showed a unique profile of communication, with core deficits in communication rate, joint attention, and communicative gestures.
9. Umeda S, Mimura M, Kato M. {{Acquired personality traits of autism following damage to the medial prefrontal cortex}}. {Soc Neurosci};2009 (Jul 27):1-11.
Recent neuroimaging studies on « theory of mind » have demonstrated that the medial prefrontal cortex (PFC) is involved when subjects are engaged in various kinds of mentalising tasks. Although a large number of neuroimaging studies have been published, a relatively small amount of neuropsychological evidence supports involvement of the medial PFC in theory of mind reasoning. We recruited two neurological cases with damage to the medial PFC and initially performed the standard neuropsychological assessments for intelligence, memory, and executive functions. To examine theory of mind performance in these two cases, four kinds of standard and advanced tests for theory of mind were used, including first- and second-order false belief tests, the strange stories test, and the faux pas recognition test. Both patients were also requested to complete the questionnaire for the autism-spectrum quotient. Neither case showed impairment on standard theory of mind tests and only mild impairments were seen on advanced theory of mind tests. This pattern of results is basically consistent with previous studies. The most interesting finding was that both cases showed personality changes after surgical operations, leading to characteristics of autism showing a lack of social interaction in everyday life. We discuss herein the possible roles of the medial PFC and emphasize the importance of using multiple approaches to understand the mechanisms of theory of mind and medial prefrontal functions.
