Nathan Ward

The pervasive nature of media multitasking in the last fifteen years has sparked extensive research, revealing a nuanced but predominantly negative association with executive function. Given the cognitive demands and technological landscape of the modern battlefield, there is a critical interest in understanding how these findings may or may not extend to military members. To understand this relationship, we investigated the hypothesis that self-reported media multitasking behaviors would be negatively associated with performance-based measurements of executive function in a military population. Results found no significant relationship between overall media multitasking and any measures of executive function. However, average media multitaskers performed significantly better than heavy media multitaskers in a task-switching paradigm. Furthermore, we examined whether self-regulation moderated this relationship. Unlike previous research in non-military samples, we did not find that the impact of media multitasking on executive function was more pronounced among military members with lower self-regulation. By uncovering the nuanced interplay between these variables, this research contributes to a more thorough understanding of the cognitive implications of media multitasking both in general and within a military context.

Stress carries diverse implications for perceptual, cognitive, and affective functions. One population particularly susceptible to acute stress-induced cognitive changes are individuals with high-stress jobs (e.g., military personnel). These individuals are often tasked with maintaining peak cognitive performance, including memory, spatial navigation, and decision-making under threatening and uncertain conditions. Previous research has separately examined decision-making under conditions of stress or uncertainty (i.e., ambiguous discrimination between friends and foes). However, questions remain about how operationally relevant stress impacts memory encoding and recall, or spatial learning, as well as how uncertainty may impact decision-making during stress. To address this gap, we examined the influence of a military-relevant emotional stressor on a series of cognitive tasks including recognition memory task (RMT), spatial orienting task (SOT), and shoot/don’t shoot decision making (DMT). To examine the effects of uncertainty and stress we varied the stimulus clarity in the DMT. We utilized threat of shock (TOS) as a high-stakes outcome for decision errors. TOS increased sympathetic arousal but did not affect subjective emotional or HPA responses. TOS influenced decision times and confidence ratings in the DMT, but not response sensitivity or response bias. DMT performance varied by stimulus clarity (uncertainty) but did not differ between stress conditions. TOS did not influence recognition memory or spatial orienting. In sum, high levels of stress and uncertainty characterize military operations, yet stress experienced in military contexts can be difficult to induce in laboratory settings. We discuss several avenues for future research, including methodological considerations to better assess the magnitude and specificity of emotional stress-induction techniques in Soldiers.

Immersion is a crucial component to characterizing virtual reality (VR) and discovering its many implications for our lives. Studies have defined immersion as the extent that virtual environments submerge users’ perceptual systems, shut out the physical environments’ inputs, and induce engrossment in users. The present study sought to further understand the applications of immersion in virtual environments by leveraging traditional self-report measures, as well as investigating the use of distraction to quantify immersion objectively. We hypothesized that participants in immersive 3-dimensional VR would self-report higher levels of immersion and engagement compared to a non-VR condition. We also predicted that participants in the VR condition would have impaired responses to a secondary task compared to the non-VR condition. Using a within-subjects design, participants engaged in a VR meditation both on a computer screen (non-VR) and through a VR headset (VR). During the meditations, they completed a secondary detection-response task (DRT) by pressing a button in response to a tactile stimulus. We used DRT reaction times to objectively measure immersion. Following the meditations, participants completed questionnaires regarding their experiences. As predicted, participants reported that the VR condition increased their engagement and presence compared to the non-VR version of the same meditation scenario. With regard to the secondary detection task, we did not find a significant effect of VR on DRT performance, although DRT performance was numerically worse in the VR condition compared to the non-VR condition. These mixed results suggest that the use of a secondary task depends upon several factors, which we discuss.

Cranial electrotherapy stimulation (CES) delivers low-intensity electrical currents to the brain to treat anxiety, depression, and pain. Though CES is considered safe and cost-effective, little is known about side effects emerging across different contexts. Our objective was to investigate how varying physical and cognitive demands impact the frequency and intensity of CES vestibular sensations in a sample of healthy young adults. We used a 2 (stimulation: sham, active) × 2 (physical demand: static sway, dynamic sit-to-stand) × 2 (cognitive demand: single-task remain silent, dual-task count backward) repeated measures design. Vestibular sensations were measured with surveys and wearable sensors capturing balance changes. Active stimulation did not influence reported vestibular sensations. Instead, high physical demand predicted more sensation reports. High cognitive demand, but not active stimulation, predicted postural sway unsteadiness. Significant effects of active stimulation on balance were observed only during the dynamic sit-to-stand transitions. In summary, CES induces vestibular sensations only for a specific outcome under certain circumstances. Our findings imply that consumers can safely maximize the benefits of CES while ensuring they are taking steps to minimize any potential side effects by considering their context and circumstances.

Exercise and airway clearance techniques (ACTs) have been a cornerstone of treatment for people with cystic fibrosis (pwCF) for many decades. Exercise may confer both respiratory and nonrespiratory benefits for pwCF, with greater exercise capacity associated with improved survival. A wide variety of exercise interventions for pwCF have been investigated. ACTs may assist in reducing respiratory symptoms for pwCF and are currently recommended to be performed daily, with the types of ACTs used varying globally. While recommended components of care, both exercise and ACTs are time-intensive and maintaining adherence to the recommendations over the longer term can be challenging. It has been proposed that with advances in the therapeutic options for pwCF, a rationalization of the therapeutic regimen may be possible. We summarize the current evidence for the use of exercise and ACTs by pwCF, discuss the implications of the introduction of cystic fibrosis transmembrane conductance regulator modulators on both exercise and ACTs, and highlight areas for further research. Article published online: 19 December 2022 © 2022. Thieme. All rights reserved. Thieme Medical Publishers, Inc. 333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

One growing area of multitasking research involves a focus on performing cognitive and motor tasks in tandem. In these situations, increasing either cognitive or motor demands has implications for performance in both tasks, an effect which is thought to be due to competing neural resources. Separate research suggests that non-invasive brain stimulation may offer a means to mitigate performance decrements experienced during multitasking. In the present study, we investigated the degree to which a commercially available non-invasive brain stimulation device (Halo Sport) alters balance performance in the presence of different types of cognitive demands. Specifically, we tested if performing a secondary cognitive task impacts postural sway in healthy young adults and if we could mitigate this impact using transcranial direct current stimulation (tDCS) applied over the primary motor cortex. Furthermore, we included conditions of unstable and stable surfaces and found that lower surface stability increased postural sway. In addition, we found that cognitive load impacted postural sway but in the opposite pattern we had anticipated, with higher sway found in the single-task control condition compared to executive function conditions. Finally, we found a small but significant effect of tDCS on balance with decreased sway for active (compared to sham) tDCS.

Standing upright on stable and unstable surfaces requires postural control. Postural control declines as humans age, presenting greater risk of fall-related injury and other negative health outcomes. Secondary cognitive tasks can further impact balance, which highlights the importance of coordination between cognitive and motor processes. Past research indicates that this coordination relies on executive function (EF; the ability to control, maintain, and flexibly direct attention to achieve goals), which coincidentally declines as humans age. This suggests that secondary cognitive tasks requiring EF may exert a greater influence on balance compared to non-EF secondary tasks, and this interaction could be exaggerated among older adults. In the current study, we had younger and older adults complete two Surface Stability conditions (standing upright on stable vs. unstable surfaces) under varying Cognitive Load; participants completed EF (Shifting, Inhibiting, Updating) and non-EF (Processing Speed) secondary cognitive tasks on tablets, as well as a single task control scenario with no secondary cognitive task. Our primary balance measure of interest was sway area, which was measured with an array of wearable inertial measurement unit sensors. Replicating prior work, we found a main effect of Surface Stability with less sway on stable surfaces compared to unstable surfaces, and we found an interaction between Age and Surface Stability with older adults exhibiting significantly greater sway selectively on unstable surfaces compared to younger adults. New findings revealed a main effect of Cognitive Load on sway, with the single task condition having significantly less sway than two of the EF conditions (Updating and Shifting) and the non-EF condition (Processing Speed). We also found an interaction of Cognitive Load and Surface Stability on postural control, where Surface Stability impacted sway the most for the single task and two of the executive function conditions (Inhibition and Shifting). Interestingly, Age did not interact with Cognitive Load, suggesting that both age groups were equally impacted by secondary cognitive tasks, regardless the presence or type of secondary cognitive task. Taken together, these patterns suggest that cognitive demands vary in their impact on posture control across stable vs. unstable surfaces, and that EF involvement may not be the driving mechanism explaining cognitive-motor dual-task interference on balance.

The purpose of this study was to characterize Cognitive Motor Dual Task (CMDT) costs for a community-based sample of older adults with Motoric Cognitive Ri

Objectives: Quality dementia care, which recognizes caregivers as vital care partners, is a scarce resource. Innovative solutions like video telehealth may increase the reach of extant clinicians; however, little is known about perceived barriers and facilitators to in-home video telehealth for dementia management from the perspectives of caregivers. Methods: Twenty-four caregivers of community-dwelling Veterans with dementia participated in semi-structured interviews. Questions gathered perceived facilitators and barriers to in-home video telehealth for dementia management through experience with related technology. Transcripts were analyzed using directed content analysis which was guided by factors previously identified as influencing older adults’ adoption of technology. Results: Caregiver experience with related technology was mostly facilitative to video telehealth, which was thought best suited for follow-up care. Increased access and decreased patient-caregiver stress were potential benefits. Barriers included perceived limitations of video and the belief that persons with dementia would have limited ability to manage technological aspects and to engage in video telehealth on their own. Conclusions: This study improves our understanding of the factors that caregivers perceive as barriers and facilitators to in-home video telehealth for dementia management. Clinical Implications: Strategies to optimize video telehealth include capitalizing on caregivers’ social network and providing targeted training.