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### Neuroimaging and electrophysiology studies  Neuroimaging and electrophysiology studies continue to be a focus of many researchers. The challenges using neuroimaging techniques to study pediatric and clinical subjects are described in detail along with various strategies that can be used to collect higher quality data \citep{26754461}. One of these was an important (though frustrating) recent finding that even very small head movements can cause artifactual findings in structural MRI \citep{25498430} . Neroimaging scans were performed on 12 healthy adults while they were still or while engaged in specific types of movements including nodding, headshaking and a movement that each subject invented and then repeated during the scan run. Even during scans when subjects attempted to remain still, there was an average of 3 mm/s RMSpm (RMS displacement per minute), but it was significantly higher during the motion conditions. In general there was a 1-3% local volume loss for each 1 mm/s RMSpm increase. The greatest thickness reductions were found in the pre- and post-central cortex, in the temporal lobes and pole, and enthorhinal and parahippocampal regions. Increased thickness associated with motion was Some motion-associated increases were  seen in regions associated with deep sulci such as the medial orbital frontal and lateral frontal areas. when measured by thickness, but less so for gray matter volume measurements.  Recommendations were made to reduce head motion during scans as much as possible and then control for motion in the statistical analysis, along with using correlational analyses to determine the associations between head motion and the predictors of interest. A more recent article \citep{26654788} attempted provides an approach  to address addressing  this concern, describing concern with  a system for motion tracking and prospective motion correction and mentioning similar systems for other scanner platforms. \citep{26654788}.  Researchers have used a variety of experimental paradigms to study motor response inhibition since tic expression seems related to motor inhibition. In healthy adults, performance on a stop-signal task and a continuous performance task was examined using positron emission tomography to measure striatal D1- and D2-type receptor availability \citep{25878272}. Stop-signal reaction time was negatively correlated with both D1- and D2-type receptor activation in both the associative striaum and the sensory motor striatum. Neither D1- nor D2-type receptor activation was associated with Go reaction time or Stop signal reaction time on the continuous performance task, suggesting that these two tasks are associated with different neurochemical mechanisms related to motor response inhibition.