The intraindividual variability (IIV) of cognitive performance has been shown to increase with aging. While brain research has generally focused on mean performance, little is known about neural correlates of cognitive IIV. Nevertheless, some studies suggest that IIV relates more strongly than mean level of performance to the quality of white matter (WM). Our study aims to explore the relation between WM integrity and cognitive IIV by combining functional (fMRI) and structural (diffusion tensor imaging, DTI) imaging. Twelve young adults (aged 18–30 years) and thirteen older adults (61–82 years) underwent a battery of neuropsychological tasks, along with fMRI and DTI imaging. Their behavioral data were analyzed and correlated with the imaging data at WM regions of interest defined on the basis of (1) the fMRI‐activated areas and (2) the Johns Hopkins University (JHU) WM tractography atlas. For both methods, fractional anisotropy, along with the mean, radial, and axial diffusivity parameters, was computed. In accord with previous studies, our results showed that the DTI parameters were more related to IIV than to mean performance. Results also indicated that age differences in the DTI parameters were more pronounced in the regions activated primarily by young adults during a choice reaction‐time task than in those also activated in older adults.

With the increasing implementation of web-based, mobile health interventions in clinical trials, it is crucial for researchers to address the security and privacy concerns of patient information according to high ethical standards. The full process of meeting these standards is often made more complicated due to the use of internet-based technology and smartphones for treatment, telecommunication, and data collection; however, this process is not well-documented in the literature. The Smart Heart Trial is a single-arm feasibility study that is currently assessing the effects of a web-based, mobile lifestyle intervention for overweight and obese children and youth with congenital heart disease in Southwestern Ontario. Participants receive telephone counseling regarding nutrition and fitness; and complete goal-setting activities on a web-based application. This paper provides a detailed overview of the challenges the study faced in meeting the high standards of our Research Ethics Board, specifically regarding patient privacy. We outline our solutions, successes, limitations, and lessons learned to inform future similar studies; and model much needed transparency in ensuring high quality security and protection of patient privacy when using web-based and mobile devices for telecommunication and data collection in clinical research.

There are a number of challenges that must be faced when trying to develop AR and VR‐based Neurosurgical simulators, Surgical Navigation Platforms, and “Smart OR” systems. Trying to simulate an operating room environment and surgical tasks in Augmented and Virtual Reality is a challenge many are attempting to solve, in order to train surgeons or help them operate. What are some of the needs of the surgeon, and what are the challenges encountered (human computer interface, perception, workflow, etc). We discuss these tradeoffs and conclude with critical remarks.

Placental dysfunction is associated with a decrease in nutrients and oxygen to the fetus; the gestational age at which this happens varies depending on severity but is an important factor in outcome as it relates to when and which brain structures are most at risk. Evidence from Doppler ultrasonography of fetuses affected by severe placental dysfunction leading to intrauterine growth restriction (IUGR) suggests blood flow distribution occurs in a hierarchical manner. In IUGR, oxygenated blood is directed toward the brain, away from other fetal organs (except the fetal heart), a process referred to as brain sparing. Further evidence suggests that subcortical regions critical for homeostasis receive more blood flow, at the cost of cortical regions involved in higher-order functions. Although Doppler findings suggest that cortical regions show more variability to placental oxygenation changes, a Cochrane review found that the evidence was of moderate to low quality,¹ indicating the need for more sensitive techniques to study how placental function affects the brain. Recent work has demonstrated an association between a magnetic resonance imaging (MRI)–based measure of placental oxygenation, transverse relaxation time (T2*), and birth weight,² suggesting that T2* may similarly estimate variations in fetal brain development.