Neuroimaging Guided Transcranial Electrical Stimulation in Enhancing Surgical Skill Acquisition. Comment on Hung et al. The Efficacy of Transcranial Direct Current Stimulation in Enhancing Surgical Skill Acquisition: A Preliminary Meta-Analysis of Randomized Controlled Trials. Brain Sci. 2021, 11, 707

Surgical skill acquisition may be facilitated with a safe application of transcranial direct current stimulation (tDCS). A preliminary meta-analysis of randomized control trials showed that tDCS was associated with significantly better improvement in surgical performance than the sham control; however, meta-analysis does not address the mechanistic understanding. It is known from skill learning studies that the hierarchy of cognitive control shows a rostrocaudal axis in the frontal lobe where a shift from posterior to anterior is postulated to mediate progressively abstract, higher-order control. Therefore, optimizing the transcranial electrical stimulation to target surgical task-related brain activation at different stages of motor learning may provide the causal link to the learning behavior. This comment paper presents the computational approach for neuroimaging guided tDCS based on open-source software pipelines and an open-data of functional near-infrared spectroscopy (fNIRS) for complex motor tasks. We performed an fNIRS-based cortical activation analysis using AtlasViewer software that was used as the target for tDCS of the motor complexity-related brain regions using ROAST software. For future studies on surgical skill training, it is postulated that the higher complexity laparoscopic suturing with intracorporeal knot tying task may result in more robust activation of the motor complexity-related brain areas when compared to the lower complexity laparoscopic tasks.

Attention Guides the Motor-Timing Strategies in Finger-Tapping Tasks When Moving Fast and Slow

Human beings adapt the spontaneous pace of their actions to interact with the environment. Yet, the nature of the mechanism enabling such adaptive behavior remains poorly understood. The aim of the present contribution was to examine the role of attention in motor timing using (a) time series analysis, and (b) a dual task paradigm. In a series of two studies, a finger-tapping task was used in sensorimotor synchronization with various tempi (from 300 to 1,100 ms) and motor complexity (one target vs. six targets). Time series analyzes indicated that two different timing strategies were used depending on the speed constraints. At slow tempi, tapping sequences were characterized by strong negative autocorrelations, suggesting the implication of cognitive predictive timing. When moving at fast and close-to-spontaneous tempi, tapping sequences were characterized by less negative autocorrelations, suggesting that timing properties emerged from body movement dynamics. The analysis of the dual-task reaction times confirmed that both the temporal and spatial constraints impacted the attentional resources allocated to the finger-tapping tasks. Overall, our work suggests that moving fast and slow involve distinct timing strategies that are characterized by contrasting attentional demands.

5. Childhood Autism and Sign Communication

Chapter 5 provides a comprehensive, historical overview of the defining characteristics of autism spectrum disorder (ASD) along with the various language therapies employed to improve the communicative success of minimally verbal individuals. The various strengths and weaknesses of such approaches are analyzed as a basis for helping to determine which methods are likely to be the most successful. The history of signing in persons with ASD is examined, with a special focus on the relatively recent realization that motor skills (both gross and fine) and imitation abilities in such individuals may be severely impaired, thus limiting the effectiveness of sign interventions that do not take into consideration the motor complexity of the signs used. Since many parents and caregivers may also express reluctance to adopt a strategy that uses signs out of fear that this will prevent their child’s acquisition of speech, research dispelling this myth is provided. In addition to coverage of sign-communication interventions and strategies for promoting spontaneous communication and generalization of sign use to multiple settings, other non-oral approaches employed with persons with disabilities are presented as options, including the use of real objects, the Picture Exchange Communication System (PECS), Blissymbols, speech-generating devices, and software applications.

Nonlinear Analysis of Human Movement Dynamics Offers New Insights in the Development of Motor Control During Childhood

When aiming at assessing motor control development, natural walking (NW), and tandem walking (TW) are two locomotor tasks that allow analyzing different characteristics of motor control performance. NW is the reference locomotor task, expected to become more and more automatic with age. TW is a nonparadigmatic task used in clinics to highlight eventual impairments and to evaluate how a child deals with a new challenging motor experience. This work aims at investigating motor development in school-aged children, by assessing quantitatively their performance during TW and NW. Eighty children (6–10 years) participated in the study. Trunk acceleration data and nonlinear measures (recurrence quantification analysis (RQA), and multiscale entropy (MSE)) were used to characterize trunk postural control and motor complexity. The results were analyzed with respect to age and standard clinical assessment of TW (number of correct consecutive steps), by means of Spearman correlation coefficients. RQA and MSE allowed highlighting age-related changes in both postural control of the trunk and motor complexity, while classic standard assessment of TW resulted uniformly distributed in the different age groups. The present results suggest this quantitative approach as relevant when assessing the motor development in schoolchildren and complementary to standard clinical tests.