Biomedical subjects

Jennifer J Vasterling

Publications and source records attributed to Jennifer J Vasterling.

11 recordsLinked to original sources

PubMed2006

Neuropsychological outcomes of army personnel following deployment to the Iraq war.

CONTEXT: The effects of war-zone deployment on neuropsychological health remain poorly understood. Neuropsychological performance deficits serve as sensitive measures of neural dysfunction and are often associated with psychosocial and occupational problems. Previous studies have not conducted objective neuropsychological assessments both before and after a major war-zone deployment. OBJECTIVE: To examine objective neuropsychological outcomes of Iraq War deployment in a large military cohort. DESIGN, SETTING, AND PARTICIPANTS: The Neurocognition Deployment Health Study, a prospective, cohort-controlled study conducted at military installations. This report centers on 961 male and female active-duty Army soldiers drawn from the larger cohort. Deploying Army soldiers (n = 654) were examined prior to deployment to Iraq (April-December 2003) and shortly after return (within a mean of 73 days [median, 75 days]; January-May 2005) from Iraq deployment. A comparison group of soldiers (n = 307) similar in military characteristics but not deploying overseas during the study was assessed in sessions timed to be as close as possible to the assessment of deployers. Military unit sampling procedures facilitated representation of combat, combat support, and combat service support functions among both deployers and nondeployers. MAIN OUTCOME MEASURES: Individually administered, performance-based neuropsychological tasks. Estimates (beta; the unstandardized parameter estimate) for the absolute differences in adjusted mean outcome scores between deployed and nondeployed groups were determined using generalized estimating equations. RESULTS: Multiple linear regression analyses adjusted for battalion membership revealed that Iraq deployment, compared with nondeployment, was associated with neuropsychological compromise on tasks of sustained attention (beta = 0.11; P<.001), verbal learning (beta = -1.51; P = .003), and visual-spatial memory (beta = -3.82; P<.001). Iraq deployment was also associated with increased negative state affect on measures of confusion (beta = 1.40; P<.001) and tension (beta = 1.24; P<.001). In contrast, deployment was associated with improved simple reaction time (beta = 4.30; P = .003). Deployment effects remained statistically significant after taking into account deployment-related head injury and stress and depression symptoms. CONCLUSIONS: Deployment to Iraq is associated with increased risk of neuropsychological compromise. Findings point to the need to investigate further the impact of deployment on neural functioning. Public health implications include consideration of neuropsychological compromise in health prevention and postdeployment clinical and occupational management.

Adult↗

PubMed2006

The impact of the 1991 Gulf War on the mind and brain: findings from neuropsychological and neuroimaging research.

Many veterans of the 1991 Gulf War (GW) have complained of somatic and cognitive symptoms that may be neurological in nature. However, whether or not changes in brain function are associated with GW service continues to be debated. Studies of GW veterans using objective, performance-based neuropsychological measures have yielded inconsistent findings, with those indicating deficits among GW veterans typically revealing only relatively mild levels of neuropsychological impairment. Further, performances on objective neuropsychological tasks show little correspondence to subjective perceptions of cognitive functioning. Although preliminary magnetic resonance spectroscopy (MRS) studies demonstrate reduced N-acetylaspartate-to-creatine (NAA/Cr) ratio in select brain regions among GW veterans who report health concerns, this work requires further replication with larger, more representative samples. There is no evidence from neuroimaging studies of a non-specific effect of GW service or of changes in brain structure or function related to health status when conventional radiological methods are used. Owing to the paucity of objective exposure, baseline health data, and the now significant time elapsed since the GW, aetiological issues may never be fully resolved. Therefore, research addressing clinical management of GW veterans with neuropsychological dysfunction and neuroimaging abnormalities may prove more fruitful than exclusive focus on aetiology.

Brain↗

PubMed2006

The Neurocognition Deployment Health Study: a prospective cohort study of Army Soldiers.

Questions remain regarding the effects of military operational deployment on health. The Neurocognition Deployment Health Study addresses several gaps in the deployment health literature, including lack of baseline health data, reliance on subjective measures of exposure and health variables, prolonged intervals between redeployment and health assessments, and lack of a uniform case definition. The Neurocognition Deployment Health Study uses a prospective cohort design to assess neuropsychological outcomes associated with Iraq deployment. Methods incorporate administration of performance-based neuropsychological measures to Army soldiers before and after Iraq deployment and to nondeployed Army Soldiers assessed during comparable periods of garrison duty. Findings should have the potential to delineate neuropsychological outcomes related to combat theater deployment and to identify potential risk and protective factors related to health outcomes.

Cognition Disorders↗

PubMed2004

Global-local visual processing in posttraumatic stress disorder.

The purpose of this study was to examine a behavioral index of hemispheric asymmetry (i.e., visual hierarchical attention) in posttraumatic stress disorder (PTSD), a disorder characterized by anxiety and other emotional symptoms. A reaction time based, computerized, global-local visual paradigm was administered to 26 PTSD-diagnosed and 22 psychopathology-free right-handed, male Vietnam War zone veterans. Results indicated that PTSD-diagnosed veterans displayed slower reaction times to all targets than the no-mental disorders comparison sample. However, findings also revealed a Group x Target location interaction in which the PTSD group was slower than the no-disorders comparison sample to respond to local, but not global, targets. Moreover, relative global bias was greater among PTSD-diagnosed veterans than their no-diagnosis counterparts. Findings provide partial support for the hypothesis that PTSD may be associated with a functional cerebral asymmetry favoring the right hemisphere.

Analysis of Variance↗

PubMed2004

Suppression of attentional bias in PTSD.

Sixty combat veterans with posttraumatic stress disorder performed an emotional Stroop task under 1 of 4 contextual conditions designed to test theoretical explanations for an attentional bias suppression effect. Results revealed that when the emotional Stroop task was performed under conditions involving a future threat of either watching a combat video or giving a speech, attentional bias was inhibited. There was limited support for the prediction that the suppression effect was strongest when stressor content matched word content on the Stroop. In contrast to participants in the threat conditions, veterans who believed that they would receive additional compensation for speeded color naming or who believed that they would have no other experimental demands were slower when color naming combat-threat words. Potential theoretical explanations of the findings are discussed.

Attention↗

PubMed2004

Early symptom predictors of chronic distress in Gulf War veterans.

Although there is evidence that specific early hyperarousal, avoidance, and emotional numbing symptoms are associated with later posttraumatic stress disorder (PTSD) symptomatology among veterans, little is known about predictors of later non-PTSD-related psychological symptoms. One and 2 years after serving in the Gulf War, 348 military reservists were assessed for severity of war zone stress, PTSD, psychological distress, and stress-mediated physical complaints. Overall PTSD symptomatology and emotional numbing and hyperarousal symptom clusters increased over time, whereas re-experiencing and avoidance symptoms showed no change. Emotional numbing and hyperarousal symptoms at 1 year predicted generalized distress, depression, anxiety, hostility, and somatic symptoms at 2 years, whereas re-experiencing and avoidance symptoms did not. Findings highlight the importance of targeting early emotional numbing and hyperarousal symptom clusters to reduce longer-term psychological distress.

Adult↗

PubMed2003

Olfactory functioning in Gulf War-era veterans: relationships to war-zone duty, self-reported hazards exposures, and psychological distress.

To explore possible neurotoxic sequelae of Gulf War (GW) participation, olfactory identification performance, neurocognitive functioning, health perceptions, and emotional distress were assessed in 72 veterans deployed to the GW and 33 military personnel activated during the GW but not deployed to the war zone. Findings revealed that war-zone-exposed veterans reported more concerns about health, cognitive functioning, and depression than did their counterparts who did not see war-zone duty. There was no evidence that performances on olfactory or neurocognitive measures were related to war-zone duty or to self-reported exposure to GW toxicants. However, symptoms of emotional distress were positively correlated with self-report of health and cognitive complaints. Results do not provide support for the hypothesis that objectively-measured sensory (i.e., olfactory) or cognitive deficits are related to war-zone participation but do underscore the increasingly demonstrated association between self-reported health concerns and symptoms of emotional distress.

Adult↗

PubMed2003

Neuropsychological screening for cognitive impairment using computer-assisted tasks.

The aim of this study was to validate a computer-assisted screening battery for classifying patients into two groups, those with and without cognitive impairment. Participants were all patients referred to the neuropsychology clinics at four VA medical centers during a 1-year period. Patients meeting the study inclusionary criteria (N = 252) were administered the Neurobehavioral Evaluation System-3 (NES3) computer-assisted battery. A detailed neuropsychological examination was carried out by an experienced neuropsychologist, who diagnosed the patient as cognitively impaired or not impaired. The neuropsychologist's diagnosis was the gold standard. Recursive partitioning analyses yielded several classification procedures using the NES3 data to predict the gold standard These procedures produced a set of six NES3 tasks that provide good sensitivity and specificity in predicting di- agnosis. Sensitivity and specificity for the least random classification procedure were 0.87 and 0.67, respectively. The results suggest that computer-assisted screening methods are a promising means of triaging patients.

Adult↗

PubMed2002

Interrater reliability of neuropsychological diagnoses: a Department of Veterans Affairs cooperative study.

This study examined the interrater reliability of neuropsychological diagnoses produced by clinical neuropsychologists across 4 medical centers. These diagnoses were based on evaluations using a comprehensive battery of commonly used neuropsychological test instruments, interview, history and medical chart review. The diagnoses of individual neuropsychologists were compared to those made by members of an external review panel for each patient evaluated. Patients were first diagnosed as showing cognitive impairment versus no cognitive impairment. If a patient was diagnosed as impaired, a specific neuropsychological diagnosis was assigned. The diagnostic classification for cognitive impairment was moderately reliable [kappa = .48 +/- s.e.(kappa) = .062]. The interrater reliability for specific diagnoses was in the fair to good range [kappa = .44 +/- s.e.(kappa) = .029]. These levels of reliability are comparable to those found for other psychiatric and neurologic specialties and for medical diagnoses made by other health care disciplines.

Adult↗

PubMed2002

Attention, learning, and memory performances and intellectual resources in Vietnam veterans: PTSD and no disorder comparisons.

Attention, learning, memory, and estimated intellectual potential were examined in 26 Vietnam veterans diagnosed with posttraumatic stress disorder (PTSD) and in 21 Vietnam veterans without mental disorders. Results revealed PTSD-associated cognitive deficits on tasks of sustained attention, working memory, initial learning, and estimated premorbid intelligence but not on measures of focus of attention, shift of attention, or memory savings. Cognitive task performances adjusted for estimated native intelligence remained negatively correlated with PTSD severity. An intellectual measure adjusted for cognitive task performances was negatively correlated with PTSD severity, even after the authors statistically controlled the level of combat exposure. Results suggested that although intellectual resources may constitute a vulnerability-protective factor for PTSD development, PTSD was associated with cognitive impairment independent of intellectual functioning.

Attention↗

PubMed2002

Cognitive components of deficit awareness in Alzheimer's disease.

Awareness of deficit was examined in 24 patients with Alzheimer's disease (AD) and their spouses (for a total of 48 participants) using performance prediction-postdiction and questionnaire discrepancy (QD) paradigms. Participants estimated their own memory performances as well the performances of spouses and of a fictional, memory-disordered patient observed on videotape. Patients overpredicted self-performances, but the extent of overestimation decreased for postdictions. Patients and caregivers accurately estimated caregiver performances but overestimated performances of the fictional patient. QD data revealed that patients underestimated their difficulties performing daily functioning tasks as compared with caregiver reports. Awareness of deficit is a complex ability, involving dissociable cognitive processes. AD patients may display intact immediate awareness of memory dysfunction but fail to incorporate incidents of memory failure into generalized self-belief systems.

Aged↗