Self-Control Measurement Methodologies: An Integrative Approach.

The study of self-control occurs in many different types of experimental settings using a wide range of methodologies. In addition, measures of self-control vary in their procedures and operational definitions from simple questionnaires to complex scenarios where individuals must choose to act or not. The present summary draws on trends within the literature using widely accepted measures of self-control.

The effect of using activity workstations on heart rate variability during complex cognitive tasks.

The purpose of the current study was to examine the effects of using an activity workstation on the physiological stress response as measured by heart rate variability while completing cognitively demanding tasks. Eleven college students (6 females; age: 19.4 ± 0.

Sleep and Organizational Behavior: Implications for Workplace Productivity and Safety.

The interaction between sleep and work-related behaviors influence many aspects of employee performance, safety, and health as well as organizational-level success. Although it is well established that quantity and quality of sleep can affect different types of task performance and personal health, the interactions between sleep habits and organizational behaviors have received much less attention. It is important to examine how sleep habits and workplace behaviors relate and the role of the underlying circadian rhythm on the potential impact of sleep and sleepiness in the workplace.

Task-dependent cold stress during expeditions in Antarctic environments.

This study seeks to understand the degree of body cooling, cold perception and physical discomfort during Antarctic tour excursions. Eight experienced expedition leaders across three Antarctic cruise voyages were monitored during occupational tasks: kayaking, snorkelling and zodiac outings. Subjective cold perception and discomfort were recorded using a thermal comfort assessment and skin temperature was recorded using a portable data logger.

Decreasing Sedentary Behavior: Effects on Academic Performance, Meta-Cognition, and Sleep.

There is growing interest in using activity workstations as a method of increasing light physical activity in normally sedentary environments. The current study ( = 117) compared the effects of studying in college students while slowly pedaling a stationary bike with a desktop with studying at traditional desks across 10 weeks in an academic semester. The students were assigned to study either on the stationary bike or at a traditional desk located in the campus library for a minimum of 2 h a week.

Performance awareness: Predicting cognitive performance during simulated shiftwork using chronobiological measures.

Physiological tracers of circadian rhythms and a performance awareness index were examined as predictors of cognitive performance during two sleep deprivation conditions common to occupational shiftwork. Study 1: Thirty-three sleep-deprived participants completed a simulated nightshift. Study 2: Thirty-two partially sleep-deprived participants completed a simulated dayshift.

Ergonomics in the arctic - a study and checklist for heavy machinery in open pit mining.

Background: Heavy mining vehicle operators at arctic mines have a high risk of discomfort, musculoskeletal disorders and occupational accidents. There is a need for tailored approaches and safety management tools that take into account the specific characteristics of arctic work environments.

Objective: The aim of this study was to develop a holistic evaluation tool for heavy mining vehicles and operator well-being in arctic mine environments.

The cold driver: Cold stress while driving results in dangerous behavior.

Cool vehicle cabin temperatures can induce short-term non-hypothermic cold stress. The current study created a cold condition to examine the impact of cold stress on driving behavior. Forty-four participants drove a high-fidelity driving simulator during a thermal neutral or local torso cooled condition.

Interactions between sleep habits and self-control.

Good sleep habits and effective self-control are important components of successful functioning. Unfortunately chronic sleep loss and impaired self-control are common occurrences for many individuals which can lead to difficulty with daily self-control issues such as resisting impulses and maintaining attentive behavior. Understanding how self-control is depleted and how good sleep habits may help replenish and maintain the capacity for self-control is an important issue.

Lane heading difference: An innovative model for drowsy driving detection using retrospective analysis around curves.

Driving while sleepy is a serious contributor to automobile accidents. Previous research has shown that drowsy drivers produce systematic errors (variability) in vehicle behavior which are detectable using vehicle monitoring technology. The current study developed a new methodological approach using a vehicle heading difference metric to detect drowsy driving more effectively than other more commonly used methods.

Language dominance in children with epilepsy: concordance of fMRI with intracarotid amytal testing and cortical stimulation.

Accurate localization of language function is critical in children undergoing epilepsy surgery. Functional magnetic resonance imaging (fMRI) is a noninvasive mapping method that has begun to replace electrocortical stimulation mapping (ESM) and the intracarotid amytal test (IAT). We used both quantitative and qualitative methods to evaluate the concordance of fMRI with ESM and IAT in 20 children using a panel of language tasks.

A balancing act of the brain: activations and deactivations driven by cognitive load.

The majority of neuroimaging studies focus on brain activity during performance of cognitive tasks; however, some studies focus on brain areas that activate in the absence of a task. Despite the surge of research comparing these contrasted areas of brain function, their interrelation is not well understood. We systematically manipulated cognitive load in a working memory task to examine concurrently the relation between activity elicited by the task versus activity during control conditions.

Quantitative MRI in the very preterm brain: assessing tissue organization and myelination using magnetization transfer, diffusion tensor and T₁ imaging.

Magnetization transfer ratio (MTR), diffusion tensor imaging (DTI) parameters and T(1) relaxometry values were used to create parametric maps characterizing the tissue microstructure of the neonatal brain in infants born very premature (24-32 gestational weeks) and scanned at preterm and term equivalent age. Group-wise image registration was used to determine anatomical correspondence between individual scans and the pooled parametric data at the preterm and term ages. These parametric maps showed distinct contrasts whose interrelations varied across brain regions and between the preterm and term period.

White matter and development in children with an autism spectrum disorder.

Recent research suggests that brain development follows an abnormal trajectory in children with autism spectrum disorders (ASD). The current study examined changes in diffusivity with age within defined white matter tracts in a group of typically developing children and a group of children with an ASD, aged 6 to 14 years. Age by group interactions were observed for frontal, long distant, interhemispheric and posterior tracts, for longitudinal, radial and mean diffusivity, but not for fractional anisotropy.

Sub-patterns of language network reorganization in pediatric localization related epilepsy: a multisite study.

To study the neural networks reorganization in pediatric epilepsy, a consortium of imaging centers was established to collect functional imaging data. Common paradigms and similar acquisition parameters were used. We studied 122 children (64 control and 58 LRE patients) across five sites using EPI BOLD fMRI and an auditory description decision task.

Converging evidence for the advantage of dynamic facial expressions.

Neuroimaging evidence suggests that dynamic facial expressions elicit greater activity than static face stimuli in brain structures associated with social cognition, interpreted as greater ecological validity. However, a quantitative meta-analysis of brain activity associated with dynamic facial expressions is lacking. The current study investigated, using three fMRI experiments, activity elicited by (a) dynamic and static happy faces, (b) dynamic and static happy and angry faces, and (c) dynamic faces and dynamic flowers.

Preterm neonatal diffusion processing using detection and replacement of outliers prior to resampling.

In diffusion weighted MRI, subject motion and brain pulsation lead both to signal drop-outs and image misalignment. Unsedated neonates, with their higher heart rate and propensity for motion are particularly prone to degraded scan quality that impairs diffusion tensor estimation. Retrospective registration and robust estimators are two methods that have previously been demonstrated to address motion and intensity outliers, respectively, in diffusion data.

Optimized T1- and T2-weighted volumetric brain imaging as a diagnostic tool in very preterm neonates.

Background: T1- and T2-W MR sequences used for obtaining diagnostic information and morphometric measurements in the neonatal brain are frequently acquired using different imaging protocols. Optimizing one protocol for obtaining both kinds of information is valuable.

Objective: To determine whether high-resolution T1- and T2-W volumetric sequences optimized for preterm brain imaging could provide both diagnostic and morphometric value.

Feature-space-based FMRI analysis using the optimal linear transformation.

The optimal linear transformation (OLT), an image analysis technique of feature space, was first presented in the field of MRI. This paper proposes a method of extending OLT from MRI to functional MRI (fMRI) to improve the activation-detection performance over conventional approaches of fMRI analysis. In this method, first, ideal hemodynamic response time series for different stimuli were generated by convolving the theoretical hemodynamic response model with the stimulus timing.

The changing face of emotion: age-related patterns of amygdala activation to salient faces.

The present study investigated age-related differences in the amygdala and other nodes of face-processing networks in response to facial expression and familiarity. fMRI data were analyzed from 31 children (3.5-8.

The optimal linear transformation-based fMRI feature space analysis.

This paper proposes a method of extending the optimal linear transformation (OLT), an image analysis technique of feature space, from magnetic resonance imaging (MRI) to functional magnetic resonance imaging (fMRI) so as to improve the activation detection performance over conventional approaches of fMRI analysis. The method was: (1) ideal hemodynamic responses for different stimuli were generated by convolving the theoretical hemodynamic response model with the stimulus timing, (2) considering the ideal hemodynamic responses as hypothetical signature vectors for different activity patterns of interest, OLT was used to extract the features of fMRI data. The resultant feature space had particular geometric clustering properties.

Neural correlates of personally familiar faces: parents, partner and own faces.

Investigations of the neural correlates of face recognition have typically used old/new paradigms where subjects learn to recognize new faces or identify famous faces. Familiar faces, however, include one's own face, partner's and parents' faces. Using event-related fMRI, we examined the neural correlates of these personally familiar faces.