Pro- and antisaccades in children elicited by visual and acoustic targets - does modality matter?

Peer reviewedPublisher PD

Adherence of systematic reviews to Cochrane RoB2 guidance was frequently poor: a meta epidemiological study

Objectives: To assess whether the use of the revised Cochrane risk of bias tool for randomized trials (RoB2) in systematic reviews (SRs) adheres to RoB2 guidance. Methods: We searched MEDLINE, Embase, Cochrane Library from 2019 to May 2021 to identify SRs using RoB2. We analyzed methods and results sections to see whether risk of bias was assessed at outcome measure level and applied to primary outcomes of the SR as per RoB2 guidance. The relation between SR characteristics and adequacy of RoB2 use was examined by logistic regression analysis. Results: Two hundred-eight SRs were included. We could assess adherence in 137 SRs as 12 declared using RoB2 but actually used RoB1 and 59 did not report the number of primary outcomes. The tool usage was adherent in 69.3% SRs. Considering SRs with multiple primary outcomes, adherence dropped to 28.8%. We found a positive association between RoB2 guidance adherence and the methodological quality of the reviews assessed by AMSTAR2 (p-for-trend 0.007). Multivariable regression analysis suggested journal impact factor [first quartile vs. other quartiles] was associated with RoB2 adherence (OR 0.34; 95% CI: 0.16-0.72). Conclusions: Many SRs did not adhere to RoB2 guidance as they applied the tool at the study level rather than at the outcome measure level. Lack of adherence was more likely among low and very low quality reviews

Learning the Optimal Control of Coordinated Eye and Head Movements

Various optimality principles have been proposed to explain the characteristics of coordinated eye and head movements during visual orienting behavior. At the same time, researchers have suggested several neural models to underly the generation of saccades, but these do not include online learning as a mechanism of optimization. Here, we suggest an open-loop neural controller with a local adaptation mechanism that minimizes a proposed cost function. Simulations show that the characteristics of coordinated eye and head movements generated by this model match the experimental data in many aspects, including the relationship between amplitude, duration and peak velocity in head-restrained and the relative contribution of eye and head to the total gaze shift in head-free conditions. Our model is a first step towards bringing together an optimality principle and an incremental local learning mechanism into a unified control scheme for coordinated eye and head movements

Exploring the Fundamental Dynamics of Error-Based Motor Learning Using a Stationary Predictive-Saccade Task

The maintenance of movement accuracy uses prior performance errors to correct future motor plans; this motor-learning process ensures that movements remain quick and accurate. The control of predictive saccades, in which anticipatory movements are made to future targets before visual stimulus information becomes available, serves as an ideal paradigm to analyze how the motor system utilizes prior errors to drive movements to a desired goal. Predictive saccades constitute a stationary process (the mean and to a rough approximation the variability of the data do not vary over time, unlike a typical motor adaptation paradigm). This enables us to study inter-trial correlations, both on a trial-by-trial basis and across long blocks of trials. Saccade errors are found to be corrected on a trial-by-trial basis in a direction-specific manner (the next saccade made in the same direction will reflect a correction for errors made on the current saccade). Additionally, there is evidence for a second, modulating process that exhibits long memory. That is, performance information, as measured via inter-trial correlations, is strongly retained across a large number of saccades (about 100 trials). Together, this evidence indicates that the dynamics of motor learning exhibit complexities that must be carefully considered, as they cannot be fully described with current state-space (ARMA) modeling efforts