Functional but Inefficient Kinesthetic Motor Imagery in Adolescents with Autism Spectrum Disorder.

Whether action representation in individuals with autism spectrum disorder (ASD) is deficient remains controversial, as previous studies of action observation or imitation report conflicting results. Here we investigated the characteristics of action representation in adolescents with ASD through motor imagery (MI) using a hand rotation and an object rotation task. Comparable with the typically-developing group, the individuals with ASD were able to spontaneously use kinesthetic MI to perform the hand rotation task, as manifested by the significant biomechanical effects. However, the ASD group performed significantly slower only in the hand rotation task, but not in the object rotation task. The findings suggest that the adolescents with ASD showed inefficient but functional kinesthetic MI, implicating that their action representation might be preserved.

Changes in structural integrity are correlated with motor and functional recovery after post-stroke rehabilitation.

PURPOSE: Diffusion tensor imaging (DTI) studies indicate the structural integrity of the ipsilesional corticospinal tract (CST) and the transcallosal motor tract, which are closely linked to stroke recovery. However, the individual contribution of these 2 fibers on different levels of outcomes remains unclear. Here, we used DTI tractography to investigate whether structural changes of the ipsilesional CST and the transcallosal motor tracts associate with motor and functional recovery after stroke rehabilitation. METHODS: Ten participants with post-acute stroke underwent the Fugl-Meyer Assessment (FMA), the Wolf Motor Function Test (WMFT), the Functional Independence Measure (FIM), and DTI before and after bilateral robotic training. RESULTS: All participants had marked improvements in motor performance, functional use of the affected arm, and independence in daily activities. Increased fractional anisotropy (FA) in the ipsilesional CST and the transcallosal motor tracts was noted from pre-treatment to the end of treatment. Participants with higher pre-to-post differences in FA values of the transcallosal motor tracts had greater gains in the WMFT and the FIM scores. A greater improvement on the FMA was coupled with increased FA changes along the ipsilesional CST. CONCLUSIONS: These findings suggest 2 different structural indicators for post-stroke recovery separately at the impairment-based and function-based levels.

Sex matters: n-back modulates emotional mismatch negativity.

This work investigates the impact of task load on irrelevant emotional voice processing between the sexes. The working memory task was manipulated by asking participants to evaluate the position of a visual stimulus (0-back) and compare the position of the current stimulus with the one or two trials before (1-back and 2-back). We recorded auditory event-related potentials while presenting the emotionally spoken syllables 'dada' and acoustically matched nonvocal sounds to healthy adults. Women, not men, showed larger amplitudes of emotional mismatch negativity (MMN), presumed to reflect preattentive auditory change detection, during the 1-back task than the 0-back and 2-back tasks. Among women only weaker emotional MMN amplitudes were associated with a higher 2-back accuracy. Neither task difficulty nor sex had any effect on MMN when responding to nonvocal sounds. Our findings suggest that there are sex differences in preattentive emotional voice processing under varying levels of task load.