Lateralization of Brain Functions: A Randomized Single-Blinded Observational Study

Abstract

Background: Cerebral dominance, also known as lateralization of brain functions, is the neurologic phenomenon in which one hemisphere dominates over the other. In humans, the majority of people are of left cerebral dominance. This study aims to derive a statistical inference between determined parameters of cerebral dominance (handedness, gender, and language skills) and the 3-dimensional visual analytic skills. Objectives: To investigate the presence of a correlation between the lateralization of brain functions and visual analytic skills. This study is purely observationally and cross-sectional in design using survey tool. Despite purely observational, proper randomization and blinding were done for the participants, to prevent coverage and selection biases among participants. Methods: This cross-sectional survey targeted an audience of undergraduate medical students, 103 of them replied and fully completed an electronic survey. All participants were blinded to the outcome and aims of the study. The survey was created via Google Forms, and made available online for three days, on the university intranet system. Compiled data resulted in 523 pages. Statistics were done using SPSS v.20, Microsoft Excel 2016, and Shodor-Interactivate software. Referencing for this paper were retrieved via a detailed systematic review of literature databases while carrying out critical evaluation of evidence. The databases included: PubMed, the Cochrane Library, Scopus, OpenGrey, and Google Scholar. Results: Males and females participated in the survey, 34 and 69 participants respectively. Approximately 88.4% of participants were right-handed. Mapped participants’ demographics included: age, gender, handedness, siblings’ and parents’ handedness, the number of siblings and birth order, and the number of spoken languages. Statistics have proven that there was no significant correlation between the 3D-visual skills and any of the tested parameters. Significance was considered at an alpha value of 0.05 Conclusions: The tested hypothesis regarding the presence of potential correlation between handedness (and other parameters of cerebral dominance) with the three-dimensional visual analytic skills, were proven to be non-existent.