RESUMEN

INTRODUCTION: Resilience is the ability to maintain or quickly return to a stable physical and psychological equilibrium despite experiencing stressful events. Flexibility of the autonomic nervous system is particularly important for adaptive stress responses and may contribute to individual differences in resilience. Power spectrum analysis of heart rate variability (HRV) allows measurement of sympathovagal balance, which helps to evaluate autonomic flexibility. The present study investigated HRV as a broad index of resilience. MATERIALS AND METHODS: Twenty-four male participants from the Army National Guard Special Forces completed psychological measures known to relate to resilience and had HRV measured while undergoing stressful virtual environment scenarios. Pearson product-moment correlations were used to explore the relationships between HRV and resilience factors. All research was conducted with the oversight of the Human Subjects Review Committee of Fuller Theological Seminary. RESULTS: Trends toward significance were reported in order to provide results that would reasonably be expected in a study of higher power. Trends between resilience factors and HRV were found only during specific stress-inducing simulations (see Tables III). CONCLUSION: Greater resilience to stress was associated with HRV during nonstress periods. Higher levels of resilience to traumatic events were associated with HRV during circumstances that were more stressful and emotionally distressing. Post hoc analysis revealed that specific factors including flexibility, emotional control, and spirituality were driving the relationship between general resilience and HRV following emotionally laden stressors. Less stress vulnerability was associated with HRV following intermittent brief stressors. In sum, HRV appears to represent some aspects of an individual's overall resilience profile. Although resilience remains a complex, multidimensional construct, HRV shows promise as a global psychophysiological index of resilience. This study also offers important perspectives concerning ways to optimize both physical and psychological health.

Asunto(s)

RESUMEN

Allostatic load (AL) is a complex clinical construct, providing a unique window into the cumulative impact of stress. However, due to its inherent complexity, AL presents two major measurement challenges to conventional statistical modeling (the field's dominant methodology): it is comprised of a complex causal network of bioallostatic systems, represented by an even larger set of dynamic biomarkers; and, it is situated within a web of antecedent socioecological systems, linking AL to differences in health outcomes and disparities. To address these challenges, we employed case-based computational modeling (CBM), which allowed us to make four advances: (1) we developed a multisystem, 7-factor (20 biomarker) model of AL's network of allostatic systems; (2) used it to create a catalog of nine different clinical AL profiles (causal pathways); (3) linked each clinical profile to a typology of 23 health outcomes; and (4) explored our results (post hoc) as a function of gender, a key socioecological factor. In terms of highlights, (a) the Healthy clinical profile had few health risks; (b) the pro-inflammatory profile linked to high blood pressure and diabetes; (c) Low Stress Hormones linked to heart disease, TIA/Stroke, diabetes, and circulation problems; and (d) high stress hormones linked to heart disease and high blood pressure. Post hoc analyses also found that males were overrepresented on the High Blood Pressure (61.2%), Metabolic Syndrome (63.2%), High Stress Hormones (66.4%), and High Blood Sugar (57.1%); while females were overrepresented on the Healthy (81.9%), Low Stress Hormones (66.3%), and Low Stress Antagonists (stress buffers) (95.4%) profiles.

RESUMEN

Mental health disorders are the signature wounds of war resulting from extended U.S. Military conflicts in the Middle East [1]. In an effort to abate the number of Service Members that develop mental health disorders in these conflicts, USC-ICT has created the Stress Resilience in Virtual Environments (STRIVE) project, a set of highly realistic virtual reality combat scenarios and resilience-building sessions designed for pre-deployed military personnel. This short-paper looks at self-reported differences in personality, emotion control, and presence between two different groups, pre-military and non-military, of pilot subjects that tested a prototype of the first four modules of STRIVE.

Asunto(s)

RESUMEN

The stressful experiences that have been characteristic of the combat environments in Iraq and Afghanistan have produced significant numbers of returning service members at risk for developing posttraumatic stress disorder and other psychosocial/behavioral health conditions. This paper describes a set of projects that are expanding the content for inclusion in a newly updated "Virtual Iraq/Afghanistan" Virtual Reality system for the delivery of exposure therapy (VRET) for PTSD with Service Members and Veterans. In addition to the complete rebuilding of this VRET system using the latest version of the Unity Game Engine, the system's content and functionality has been expanded to now support the use of VRET with combat medics/corpsmen and persons who have experienced military sexual trauma (MST). The focus of this paper is to present the rationale and general overview of the progress on these projects that will provide new relevant and customizable options for conducting VRET with a wider range of trauma experiences.

Asunto(s)

RESUMEN

The incidence of posttraumatic stress disorder (PTSD) in returning OEF/OIF military personnel is creating a significant healthcare challenge. This has served to motivate research on how to better develop and disseminate evidence-based treatments for PTSD. One emerging form of treatment for combat-related PTSD that has shown promise involves the delivery of exposure therapy using immersive Virtual Reality (VR). Initial outcomes from open clinical trials have been positive and fully randomized controlled trials are currently in progress to further validate this approach. Based on our research group's initial positive outcomes using VR to emotionally engage and successfully treat persons undergoing exposure therapy for PTSD, we have begun development in a similar VR-based approach to deliver stress resilience training with military service members prior to their initial deployment. The Stress Resilience In Virtual Environments (STRIVE) project aims to create a set of combat simulations (derived from our existing Virtual Iraq/Afghanistan exposure therapy system) that are part of a multi-episode narrative experience. Users can be immersed within challenging combat contexts and interact with virtual characters within these episodes as part of an experiential learning approach for training a range of psychoeducational and cognitive-behavioral emotional coping strategies believed to enhance stress resilience. The STRIVE project aims to present this approach to service members prior to deployment as part of a program designed to better prepare military personnel for the types of emotional challenges that are inherent in the combat environment. During these virtual training experiences users are monitored physiologically as part of a larger investigation into the biomarkers of the stress response. One such construct, Allostatic Load, is being directly investigated via physiological and neuro-hormonal analysis from specimen collections taken immediately before and after engagement in the STRIVE virtual experience.

Asunto(s)

RESUMEN

The regional distribution of degeneration of the corpus callosum (CC) in dementia is not yet clear. This study compared regional CC size in participants (n = 179) from the Cache County Memory and Aging Study. Participants represented a range of cognitive function: Alzheimer's disease (AD), vascular dementia (VaD), mild ambiguous (MA-cognitive problems, but not severe enough for diagnosis of dementia), and healthy older adults. CC outlines obtained from midsagittal magnetic resonance images were divided into 99 equally spaced widths. Factor analysis of these callosal widths identified 10 callosal regions. Multivariate analysis of variance revealed significant group differences for anterior and posterior callosal regions. Post-hoc pairwise comparisons of CC regions in patient groups as compared to the control group (controlling for age) revealed trends toward smaller anterior and posterior regions, but not all were statistically significant. As compared to controls, significantly smaller anterior and posterior CC regions were found in the AD group; significantly smaller anterior CC regions in the VaD group; but no significant CC regional differences in the MA group. Findings suggest that dementia-related CC atrophy occurs primarily in the anterior and posterior portions.

Asunto(s)

RESUMEN

Results from epidemiologic studies of postmenopausal hormone use and dementia have been conflicting. Investigators from the Women's Health Initiative Memory Study reported that the incidence of dementia in women aged >/=65 years assigned to hormone use was increased. Here the authors report results from a prospective cohort study of 2,906 dementia-free women (1,519 hormone users and 1,387 hormone nonusers) aged > or =75 years who were recruited from a Southern California health plan in 1999 and followed through 2003. Cognitive status was assessed annually using the Telephone Interview of Cognitive Status-modified, supplemented by the Telephone Dementia Questionnaire and medical record review. The mean self-reported age at initiation of hormone use was 48.3 years for users of estrogen alone (n = 1,072) and 54.9 years for users of estrogen plus progestin (n = 447); self-reported mean durations of hormone use were 30.5 years and 23.2 years, respectively. There were 283 incident dementia cases identified during follow-up. After adjustment for age, education, and medical history, hazard ratios for incident dementia were 1.34 (95% confidence interval: 0.95, 1.89) in estrogen/progestin users and 1.23 (95% confidence interval: 0.94, 1.59) in estrogen users. These findings do not provide support for an effect of estrogen or estrogen/progestin use in preventing dementia.

Asunto(s)

Asunto(s)

RESUMEN

In this initial pilot study, a controlled clinical comparison was made of attention perforance in children with attention deficit-hyperactivity disorder (ADHD) in a virtual reality (VR) classroom. Ten boys diagnosed with ADHD and ten normal control boys participated in the study. Groups did not significantly differ in mean age, grade level, ethnicity, or handedness. No participants reported simulator sickness following VR exposure. Children with ADHD exhibited more omission errors, commission errors, and overall body movement than normal control children in the VR classroom. Children with ADHD were more impacted by distraction in the VR classroom. VR classroom measures were correlated with traditional ADHD assessment tools and the flatscreen CPT. Of note, the small sample size incorporated in each group and higher WISC-III scores of normal controls might have some bearing on the overall interpretation of results. These data suggested that the Virtual Classroom had good potential for controlled performance assessment within an ecologically valid environment and appeared to parse out significant effects due to the presence of distraction stimuli.

Asunto(s)

RESUMEN

BACKGROUND: Brief screening tests have been developed to measure cognitive performance and dementia, yet they measure limited cognitive domains and often lack construct validity. Neuropsychological assessments, while comprehensive, are too costly and time-consuming for epidemiological studies. This study's aim was to develop a psychometrically valid telephone administered test of cognitive function in aging. METHODS: Using a sequential hierarchical strategy, each stage of test development did not proceed until specified criteria were met. The 30 minute Cognitive Assessment of Later Life Status (CALLS) measure and a 2.5 hour in-person neuropsychological assessment were conducted with a randomly selected sample of 211 participants 65 years and older that included equivalent distributions of men and women from ethnically diverse populations. RESULTS: Overall Cronbach's coefficient alpha for the CALLS test was 0.81. A principal component analysis of the CALLS tests yielded five components. The CALLS total score was significantly correlated with four neuropsychological assessment components. Older age and having a high school education or less was significantly correlated with lower CALLS total scores. Females scored better overall than males. There were no score differences based on race. CONCLUSION: The CALLS test is a valid measure that provides a unique opportunity to reliably and efficiently study cognitive function in large populations.

Asunto(s)

RESUMEN

Global cognitive screening tests are increasingly used in clinical and research settings. However, many have not been developed following systematic psychometric principles; thus, construct validity is not clearly defined. It is the aim of this study to identify the cognitive domains that are associated with the total score from the Telephone Interview for Cognitive Status-modified (TICS-m). Data came from 104 women (75 years of age and older) who were participants in a longitudinal study of dementia and had been given the TICS-m and a battery of standardized neuropsychological tests. Factor analysis of all these neuropsychological tests yielded six interpretable factors. episodic memory for words, episodic memory for contextual information, working memory, episodic memory for nonverbal information, attention, and visuospatial processing efficiency. The TICS-m score showed modest associations with several distinct cognitive domains, including episodic memory for words and nonverbal information and attention.

Asunto(s)

RESUMEN

Treatment and rehabilitation of the cognitive, psychological, and motor sequelae of central nervous system dysfunction often relies on assessment instruments to inform diagnosis and to track changes in clinical status. Typically, these assessments employ paper-and-pencil psychometrics, hands-on analog/computer tests, and rating of behavior within the context of real-world functional environments. Virtual reality offers the option to produce and distribute identical "standard" simulation environments in which performance can be measured and rehabilitated. Within such digital scenarios, normative data can be accumulated for performance comparisons needed for assessment/diagnosis and for treatment/rehabilitation purposes. In this manner, reusable archetypic virtual environments constructed for one purpose can also be applied for applications addressing other clinical targets. This article will provide a review of such a retooling approach using a virtual classroom simulation that was originally developed as a controlled stimulus environment in which attention processes could be systematically assessed in children with attention-deficit/hyperactivity disorder. This system is now being applied to other clinical targets including the development of tests that address other cognitive functions, eye movement under distraction conditions, social anxiety disorder, and the creation of an earthquake safety training application for children with developmental and learning disabilities.

Asunto(s)

RESUMEN

Based on anecdotal reports and a few empirical studies, there is concern about the cognitive effects of cancer and its treatment effects among adults. A cross-sectional comparison of the cognitive performance of 541 elderly women who reported at least one hospitalization for cancer and 3,123 who had no reported hospitalizations for cancer was conducted. The difference between cancer survivors and those with no history of cancer on a screening test of global cognitive functioning was not significant, nor were there differences on a subtest of the global test that assesses verbal memory. Older women who report being hospitalized for cancer as adults may perform similar to women with no history of cancer on rudimentary cognitive tasks.

Asunto(s)

RESUMEN

The epidemiology of prolapse and incontinence questionnaire (EPIQ) was developed to screen for female pelvic floor disorders (PFD). Content and face validity, reliability, internal consistency and criterion validity of the EPIQ to detect the presence of pelvic organ prolapse (POP), stress urinary incontinence (SUI), overactive bladder (OAB) and anal incontinence (AI) is presented. Cronbach's alpha; Spearman's, kappa, intraclass correlations, factor analysis and Chi-Squared tests were used for analysis. Questions related to PFD proved internally consistent (alpha = 0.91) and reproducible (correlations >0.70) for all but three items on the EPIQ. Positive and negative predictive values of the EPIQ to detect PFD were: POP = 76% and 97%, SUI = 88% and 87%, OAB = 77% and 90% and AI = 61% and 91% respectively. EPIQ is a psychometrically validated screening instrument that may identify women at high risk of having pelvic floor disorders in large undiagnosed populations.

Asunto(s)

RESUMEN

BACKGROUND: The association between blood pressure (BP) and dementia is not easily interpreted, but some prospective studies suggest that dementia may lower BP. OBJECTIVE: To examine the relationship between BP during a 10-year period and the prevalence of dementia. DESIGN: Comparison of longitudinal BP between participants who had dementia, participants who were cognitively impaired, and unimpaired participants selected from an ongoing cohort study. SETTING: A prepaid health plan in southern California. PARTICIPANTS: Three hundred participants had dementia, 285 were cognitively impaired, and 585 were unimpaired. MAIN OUTCOME MEASURES: Retrospective medical record review of up to 3 randomly selected BP measurements per year for the 10 years before cognitive classification of each participant. RESULTS: Systolic BP increased with time in the unimpaired participants, and increased less in women who developed cognitive impairment and in women who developed dementia. Diastolic BP declined significantly (P<.001) with time in all 3 groups. Compared with unimpaired women, the adjusted rate of decline in diastolic BP was significantly (P = .04) greater for the women who developed dementia. CONCLUSIONS: These findings are consistent with previous findings that the relationship between BP and dementia is affected by age at data collection. Valid inferences about the effect of BP on the development of dementia require prospective data collection in which subjects are free of dementia or cognitive impairment at enrollment.

Asunto(s)

RESUMEN

OBJECTIVE: The purpose of this study was to assess the validity of Visual Analog Scales in urogynecologic research. STUDY DESIGN: In phase I, 35 women completed short forms of the urogenital distress inventory, incontinence impact questionnaire, and Beck depression inventory fast screen using the Likert-type scale and Visual Analog Scale formats. Reliability was estimated with Spearman's correlations and Cronbach's alpha; construct validity was assessed with the use of factor analyses. In phase II, 101 women were recruited for the test-retest reliability assessment of the Visual Analog Scale formats of the urogenital distress inventory and incontinence impact questionnaire short forms. Reproducibility was analyzed with intraclass correlations. RESULTS: In phase I, correlations between the Likert-type scale and the Visual Analog Scale were good: urogenital distress inventory (0.748), incontinence impact questionnaire (0.787), and Beck depression inventory fast screen (0.852; P <.05). In phase II, intraclass correlations were 0.898 and 0.938 for the urogenital distress inventory and incontinence impact questionnaire scores, respectively ( P <.001). CONCLUSION: The Visual Analog Scale is a simple, reliable, and reproducible method for the assessment of quality of life in urogynecologic research.

Asunto(s)

RESUMEN

The aim of this research was to compare the data analytic applicability of a backpropagated neural network with that of regression analysis. Thirty individuals between the ages of 64 and 86 (Mean age = 73.6; Mean years education = 15.4; % women = 50) participated in a study designed to validate a new test of spatial ability administered in virtual reality. As part of this project a standard neuropsychological battery was administered. Results from the multiple regression model R(2) = .21, p < .28; Standard Error = 18.01) were compared with those of a backpropagated ANN (R(2) = .39, p < .02; Standard Error = 13.07). This 18% increase in prediction of a common neuropsychological problem demonstrated that an ANN has the potential to outperform a regression.

Asunto(s)

RESUMEN

The visuospatial ability referred to as mental rotation has been shown to produce one of the largest and most consistent sex differences, in favor of males, in the cognitive literature. The current study utilizes both a paper-and-pencil version of the mental rotations test (MRT) and a virtual environment for investigating rotational ability among 44 adult subjects. Results replicate sex differences traditionally seen on paper-and-pencil measures, while no sex effects were observed in the virtual environment. These findings are discussed in terms of task demands and motor involvement. Sex differences were also seen in the patterns of correlations between rotation tasks and other neuropsychological measures. Current results suggest men may rely more on left hemisphere processing than women when engaged in rotational tasks.

Asunto(s)

RESUMEN

OBJECTIVE: The authors examined whether older adults respond comparably to two standard depression instruments rating symptoms by frequency/duration or degree of severity/"bother." METHODS: Data for this cross sectional analysis of a prospective cohort came from 699 community-dwelling individuals within the communities of Durham, North Carolina, and New Haven, Connecticut. Differences in response between the Center for Epidemiological Studies-Depression (CES-D) survey, emphasizing symptom frequency, were compared with the Hopkins Symptom Checklist (HSCL) subscale, emphasizing bother or discomfort related to those symptoms. Socioeconomic, demographic, and clinical characteristics for subjects with the greatest difference between standardized scale scores were analyzed with multivariable logistic regression. RESULTS: Older persons differed in their responses between the two instruments, despite similar content. Individuals in the highest quartile of difference between the two scales (indicating more bother than symptom frequency) had significantly more education, higher income, and were less often African American, with no differences in health conditions. Moreover, these specific socioeconomic and ethnic characteristics remained significant in multivariable analyses. CONCLUSIONS: Older persons not only differed significantly in their responses between depression instruments based on one dimension or the other, although with similar content, but response was significantly associated with specific subject characteristics. The heterogeneity of older patient populations suggests that recognition of depressive symptoms should include both constructs of symptom-associated discomfort and symptom frequency to achieve more accurate assessment.

Asunto(s)

RESUMEN

Coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) can produce a higher incidence of neuropsychological complications than other types of highly invasive noncardiac vascular surgery. Cognitive complications most likely arise from either embolization or hypoxia. An alternative surgical procedure has been developed that allows CABG to be performed without stopping the heart ("off-pump" CABG, or OPCABG). This study examined the neuropsychological performance of patients undergoing OPCABG, hypothesizing that patients undergoing OPCABG would show fewer cognitive deficits than patients whose hearts were stopped. A 1-hr neuropsychological battery was administered preoperatively to 43 patients before prospective randomization to either CPB CABG or OPCABG, and again to 34 of those patients 2 to 3 months postoperatively by an examiner blind to surgical condition. Neuropsychological status did not change 2.5 months postsurgically in either OPCABG or CABG groups. However, both groups showed dramatic presurgical cognitive deficits in multiple domains, particularly verbal memory and psychomotor speed. This corroborates previous research suggesting that patients requiring CABG surgery may evidence significant presurgical cognitive deficits as a result of existing vascular disease.

Asunto(s)