30543
Differences in Cortical Activation Patterns between Children with and without Autism Spectrum Disorder (ASD) during Interpersonal Synchrony Tasks.
Children with Autism Spectrum Disorder (ASD) have difficulties with social interaction as well as socially-embedded motor skills such as imitation and interpersonal synchrony (IPS). These behaviors share common neural mechanisms which may better explain the core symptoms of this population. Using functional Magnetic Resonance Imaging (fMRI), previous studies have reported atypical patterns of activation in the Mirror Neuron Systems (MNS) of children with ASD compared to typically developing children (TD). However, the tasks were restricted to simple finger movements and did not involve upright and naturalistic face-to-face interactions. We address these limitations through the use of functional near-infrared spectroscopy (fNIRS) to investigate cortical activation during a naturalistic reach to cleanup task.
Objectives:
We compared MNS activation between children with and without ASD during a reach to cleanup, interpersonal synchrony task.
Methods:
Sixteen children with ASD and 17 age- and gender-matched, typically developing children without ASD between 6 and 17 years of age participated. Each child wore a cap embedded with two 3x3 fNIRS probe sets that covered the bilateral MNS regions, including inferior frontal gyrus (IFG), superior temporal sulcus (STS), and inferior parietal lobe (IPL). The children were seated at a table face to face with an adult social partner. Multiple blocks were arranged in a circular fashion. The task involved cleaning up the blocks into a container across 3 conditions: a) Watch: the child observed the adult cleaning up the blocks, b) Do: the child cleaned up the blocks on their own, and c) IPS: the child cleaned up the blocks along with the adult by matching the block location and color/shape. Eighteen trials (6 per condition) were collected in a random order. The oxy-hemoglobin response of the fNIRS signal was analyzed per channel.
Results:
Children with ASD had decreased spatial and temporal accuracy during the IPS condition compared to their TD peers. Compared to other cortical regions, both groups showed higher STS activation during Watch and higher IFG activation during Do and IPS. Both groups showed greater cortical activation during Do and IPS conditions compared to Watch. The IPS > Do pattern of activation was found in the right IFG region in the TD group and the left IFG and right STS regions in the ASD group. In terms of hemispheric differences, during movement conditions of Do, both groups showed significant left lateralization (TD group for the STS region and ASD for the IFG region). In contrast, children with ASD showed right lateralization over the STS region during IPS. Most importantly, children with ASD showed lower STS and IFG and greater IPL activation compared to the TD children.
Conclusions:
Children with ASD had more IPS errors, decreased bilateral STS and IFG activation, and greater compensatory IPL activation than the control group. Children with ASD have markedly different patterns of cortical activation than TD children. In the future, we will examine therapeutic contexts that could normalize the patterns of cortical activation in children with ASD, for example, effects of music/no music or visual/auditory cueing, etc.