Article

Kana RK, Keller TA, Cherkassky VL, et al. Sentence comprehension in autism: thinking in pictures with decreased functional connectivity

Center for Cognitive Brain Imaging, Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Brain (Impact Factor: 9.2). 10/2006; 129(Pt 9):2484-93. DOI: 10.1093/brain/awl164
Source: PubMed

ABSTRACT

Comprehending high-imagery sentences like The number eight when rotated 90 degrees looks like a pair of eyeglasses involves the participation and integration of several cortical regions. The linguistic content must be processed to determine what is to be mentally imaged, and then the mental image must be evaluated and related to the sentence. A theory of cortical underconnectivity in autism predicts that the interregional collaboration required between linguistic and imaginal processing in this task would be underserved in autism. This functional MRI study examined brain activation in 12 participants with autism and 13 age- and IQ-matched control participants while they processed sentences with either high- or low-imagery content. The analysis of functional connectivity among cortical regions showed that the language and spatial centres in the participants with autism were not as well synchronized as in controls. In addition to the functional connectivity differences, there was also a group difference in activation. In the processing of low-imagery sentences (e.g. Addition, subtraction and multiplication are all math skills), the use of imagery is not essential to comprehension. Nevertheless, the autism group activated parietal and occipital brain regions associated with imagery for comprehending both the low and high-imagery sentences, suggesting that they were using mental imagery in both conditions. In contrast, the control group showed imagery-related activation primarily in the high-imagery condition. The findings provide further evidence of underintegration of language and imagery in autism (and hence expand the understanding of underconnectivity) but also show that people with autism are more reliant on visualization to support language comprehension.

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Available from: Nancy Minshew, Dec 12, 2013
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    • "During scanning, participants completed the task described by Kana et al. (2006); stimulus materials were provided by Kana. They read short declarative statements displayed for up to 4 s until a response was made, designed to have imageable content that was low ( " Addition, subtraction and multiplication are all math skills " ) or high ( " Sometimes fluffy clouds can look just like round cotton balls " ). "
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    ABSTRACT: Although Autism Spectrum Disorder (ASD) is generally a lifelong disability, a minority of individuals with ASD overcome their symptoms to such a degree that they are generally indistinguishable from their typically-developing peers. That is, they have achieved an optimal outcome (OO). The question addressed by the current study is whether this normalized behavior reflects normalized brain functioning, or alternatively, the action of compensatory systems. Either possibility is plausible, as most participants with OO received years of intensive therapy that could alter brain networks to align with typical function or work around ASD-related neural dysfunction. Individuals ages 8 to 21years with high-functioning ASD (n=23), OO (n=16), or typical development (TD; n=20) completed a functional MRI scan while performing a sentence comprehension task. Results indicated similar activations in frontal and temporal regions (left middle frontal, left supramarginal, and right superior temporal gyri) and posterior cingulate in OO and ASD groups, where both differed from the TD group. Furthermore, the OO group showed heightened “compensatory” activation in numerous left- and right-lateralized regions (left precentral/postcentral gyri, right precentral gyrus, left inferior parietal lobule, right supramarginal gyrus, left superior temporal/parahippocampal gyrus, left middle occipital gyrus) and cerebellum, relative to both ASD and TD groups. Behaviorally normalized language abilities in OO individuals appear to utilize atypical brain networks, with increased recruitment of language-specific as well as right homologue and other systems. Early intensive learning and experience may normalize behavioral language performance in OO, but some brain regions involved in language processing may continue to display characteristics that are more similar to ASD than typical development, while others show characteristics not like ASD or typical development.
    Full-text · Article · Dec 2015 · Clinical neuroimaging
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    • "Several sources document that the brains of individuals with ASD exhibit aberrant functional connectivity (Belmonte et al., 2004; Uddin et al., 2013; Kana et al., 2011; Casanova and Trippe, 2009; Muller et al., 2011; Dinstein et al., 2011), defined as the " temporal correlations between remote neurophysiological events, " (Friston, 2011) using MRI techniques (Pina-Camacho et al., 2012; Cheng et al., 2010). Many neuroimaging studies, using both functional MRI (fMRI) and diffusion tensor imaging (DTI) done during both task-specific (Koshino et al., 2005; Koshino et al., 2008; Just et al., 2007; Kana et al., 2006) and resting-state (idle) conditions (Cherkassky et al., 2006; Weng et al., 2010), have shown that individuals with ASD have reduced longrange (distant) brain connectivity when compared to people with neurotypical development. A separate set of studies have shown reduced short-range (local) connectivity (Kana et al., 2011; Koshino et al., 2005; Koshino et al., 2008; Just et al., 2007). "
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    ABSTRACT: Background: While there is increasing evidence of altered brain connectivity in autism, the degree and direction of these alterations in connectivity and their uniqueness to autism has not been established. The aim of the present study was to compare connectivity in children with autism to that of typically developing controls and children with developmental delay without autism. Methods: We assessed EEG spectral power, coherence, phase lag, Pearson and partial correlations, and epileptiform activity during the awake, slow wave sleep, and REM sleep states in 137 children aged 2 to 6. years with autism (n = 87), developmental delay without autism (n = 21), or typical development (n = 29). Findings: We found that brain connectivity, as measured by coherence, phase lag, and Pearson and partial correlations distinguished children with autism from both neurotypical and developmentally delayed children. In general, children with autism had increased coherence which was most prominent during slow wave sleep. Interpretation: Functional connectivity is distinctly different in children with autism compared to samples with typical development and developmental delay without autism. Differences in connectivity in autism are state and region related. In this study, children with autism were characterized by a dynamically evolving pattern of altered connectivity.
    Full-text · Article · Nov 2015 · EBioMedicine
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    • "For example, Koshino et al. (2005, 2008) found less brain activation in brain regions associated with verbal reasoning, and greater activation in regions associated with visual processing. Kana et al. (2006), who found unexpected activity in brain regions associated with imagery during engagement in low-imagery sentence comprehension tasks, suggested that among individuals with ASD there may be reliance upon visualization to support language comprehension. Soulières et al. (2009) found evidence suggesting a prominent role of visual processing mechanisms while examining participants engaged in the Raven's Standard Progressive Matrices (Raven et al. 2003). "
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    ABSTRACT: The present study examines the efficacy of a social skills and Theory of Mind (S.S.ToM) intervention for children with high-functioning ASD. Children were taught to identify and consider their peer's mental states, e.g., knowledge, emotions, desires, beliefs, intentions, likes and dislikes, while learning friendship-making skills and strategies, through the use of visual scaffolds in story format. Compared to two control groups, S.S.ToM participants demonstrated significantly greater gains on measures of Theory of Mind and social responsiveness. At a 3-month follow-up assessment, improvements appeared to have been maintained and continued gains were observed. These results provide support for the utility of a visually supported Theory of Mind and social skills intervention that may be delivered in community settings.
    Full-text · Article · May 2015 · Journal of Autism and Developmental Disorders
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