Estimated gray matter volume rapidly changes after a short motor task.

Skill learning induces changes in estimates of gray matter volume (GMV) in the human brain, commonly detectable with magnetic resonance imaging (MRI). Rapid changes in GMV estimates while executing tasks may however confound between- and within-subject differences. Fluctuations in arterial blood flow are proposed to underlie this apparent task-related tissue plasticity. To test this hypothesis, we acquired multiple repetitions of structural T1-weighted and functional blood-oxygen level-dependent (BOLD) MRI measurements from 51 subjects performing a finger-tapping task (FTT; á 2 min) repeatedly for 30-60 min. Estimated GMV was decreased in motor regions during FTT compared with rest. Motor-related BOLD signal changes did not overlap nor correlate with GMV changes. Nearly simultaneous BOLD signals cannot fully explain task-induced changes in T1-weighted images. These sensitive and behavior-related GMV changes pose serious questions to reproducibility across studies, and morphological investigations during skill learning can also open new avenues on how to study rapid brain plasticity.

Effectiveness of formal onboarding for facilitating organizational socialization: A systematic review.

OBJECTIVE: To investigate the effectiveness of formal onboarding programs and practices for new professionals. INTRODUCTION: New professionals may experience high levels of stress and uncertainty. Formal onboarding programs and practices aim to facilitate the socialization of new professionals by structuring early experiences. However, there is a lack of evidence-based recommendations of how to onboard new professionals. METHODS: This review considered studies that compares the effect of formal onboarding practices and programs for new professionals between 18-30 years of age (sample mean) to the effect of informal onboarding practices or 'treatment as usual' in professional organizations internationally. The outcome of interest for the review was the extent to which new professionals were socialized. The search strategy aimed to locate both published studies (dating back to year 2006) and studies accepted for publication written in English using the electronic databases Web of Science and Scopus (last search November 9 2021). Titles and abstracts were screened and selected papers were assessed by two independent reviewers against the eligibility criteria. Critical appraisal and data extraction were performed by two independent reviewers using Joanna Briggs Institutes templates. The findings were summarized in a narrative synthesis and presented in tables. The certainty of the evidence was assessed using the grading of recommendations, assessment, development and evaluations approach. RESULTS: Five studies including 1556 new professionals with a mean age of 25 years were included in the study. Most participants were new nurses. The methodological quality was assessed as low to moderate and there were high risks of bias. In three of the five included studies, a statistically significant effect of onboarding practices and programs on new professionals' adjustment could be confirmed (Cohen's d 0.13-1.35). Structured and supported on-the-job training was shown to be the onboarding strategy with the strongest support to date. The certainty of the evidence was rated as low. CONCLUSION: The results suggests that organizations should prioritize on-the-job training as a strategy to facilitate organizational socialization. For researchers, the results suggest that attention should be given to understanding how to best implement on-the-job training to ensure strong, broad, and lasting effects. Importantly, research of higher methodological quality investigating effects of different onboarding programs and practices is needed. Systematic review registration number: OSF Registries osf.io/awdx6/.