Biomedical subjects

Rodney D Vanderploeg

Publications and source records attributed to Rodney D Vanderploeg.

18 recordsLinked to original sources

PubMed2005

Florida Cognitive Activities Scale: initial development and validation.

We used a rational-empirical approach in the construction and validation of a cognitive activity scale for use with elderly populations. The scale development effort produced a 25-item scale with a reasonably high level of internal consistency in a sample of 200 elderly individuals. Scale scores were positively correlated with years of education and measures of various domains of cognitive ability. In a separate cross-validation sample, a similar pattern of reliability and validity coefficients was obtained. The full scale score was found to contribute significantly to the prediction of cognitive ability after controlling for the effects of age, education, and gender. Two subscales (Higher Cognitive Abilities and Frequent Cognitive Abilities) and a measure of self-reported maintenance of cognitive activity were also developed. In a separate study, the maintenance score was found to differ significantly between the validation sample and a sample of individuals with a history of neurological disorder, with a moderate effect size (d approximately = .7). Further cross-validation studies in minority groups and groups of varying socioeconomic status will be critical in establishing the research and clinical value of the scale and subscales.

Aged↗

PubMed2005

Factors moderating neuropsychological outcomes following mild traumatic brain injury: a meta-analysis.

There continues to be debate about the long-term neuropsychological impact of mild traumatic brain injury (MTBI). A meta-analysis of the relevant literature was conducted to determine the impact of MTBI across nine cognitive domains. The analysis was based on 39 studies involving 1463 cases of MTBI and 1191 control cases. The overall effect of MTBI on neuropsychological functioning was moderate (d = .54). However, findings were moderated by cognitive domain, time since injury, patient characteristics, and sampling methods. Acute effects (less than 3 months postinjury) of MTBI were greatest for delayed memory and fluency (d = 1.03 and .89, respectively). In unselected or prospective samples, the overall analysis revealed no residual neuropsychological impairment by 3 months postinjury (d = .04). In contrast, clinic-based samples and samples including participants in litigation were associated with greater cognitive sequelae of MTBI (d = .74 and .78, respectively at 3 months or greater). Indeed, litigation was associated with stable or worsening of cognitive functioning over time. The implications and limitations of these findings are discussed.

Brain Injuries↗

PubMed2005

Long-term neuropsychological outcomes following mild traumatic brain injury.

Mild traumatic brain injury (MTBI) is common, yet few studies have examined neuropsychological outcomes more than 1 year postinjury. Studies of nonreferred individuals with MTBI or studies with appropriate control groups are lacking, but necessary to draw conclusions regarding natural recovery from MTBI. We examined the long-term neuropsychological outcomes of a self-reported MTBI an average of 8 years postinjury in a nonreferred community-dwelling sample of male veterans. This was a cross-sectional cohort study derived from the Vietnam Experience Study. Three groups matched on premorbid cognitive ability were examined, those who (1) had not been injured in a MVA nor had a head injury (Normal Control; n = 3214), (2) had been injured in a motor vehicle accident (MVA) but did not have a head injury (MVA Control; n = 539), and (3) had a head injury with altered consciousness (MTBI; n = 254). A MANOVA found no group differences on a standard neuropsychological test battery of 15 measures. Across 15 measures, the average neuropsychological effect size of MTBI compared with either control group was -.03. Subtle aspects of attention and working memory also were examined by comparing groups on Paced Auditory Serial Addition Test (PASAT) continuation rate and California Verbal Learning Test (CVLT) proactive interference (PI). Compared with normal controls, the MTBI group evidenced attention problems in their lower rate of continuation to completion on the PASAT (odds ratio = 1.32, CI = 1.0-1.73) and in excessive PI (odds ratio = 1.66, CI = 1.11-2.47). Unique to the MTBI group, PASAT continuation problems were associated with left-sided visual imperceptions and excessive PI was associated with impaired tandem gait. These results show that MTBI can have adverse long-term neuropsychological outcomes on subtle aspects of complex attention and working memory.

Adult↗

PubMed2005

Role of executive functioning in verbal and visual memory.

G. Tremont, S. Halpert, D. J. Javorsky, and R. A. Stern (2000) found that individuals with executive dysfunction were more impaired on less structured versus more structured verbal memory tasks. In the present study, the authors investigated the relationship between executive functions and memory in patients with a history of traumatic brain injury by examining the effect of executive functioning on more structured and less structured verbal and visual memory tasks at baseline and 1-year follow-up. Matched subgroups controlled for differences in severity of neuropsychological impairment unrelated to specific executive functions. The G. Tremont et al. (2000) findings were not replicated. Results showed that when acuteness and severity of injury were controlled, executive impairment played no significant role in performance on either more or less structured memory tasks. However, regardless of structure, executive functions played a role in visual memory performance, suggesting that visual memory may be a more fluid ability than verbal memory.

Adolescent↗

PubMed2003

Predictors of postconcussion symptom complex in community dwelling male veterans.

The presence of a persistent postconcussion symptom complex (PPCSC) was examined in a non-referred sample of male veterans with a history of mild head injury and a comparison group without a history of head injury. Hierarchical logistic regression procedures were used to determine possible predictors of PPCSC using variables supported by previous research (i.e., preexisting psychiatric difficulties, demographic and social support variables, and history of an accidental injurious event). Although PPCSC was common in all groups (23% of the total sample), a significantly greater proportion of individuals in the mild head injury with loss of consciousness group (37.2%) had PPCSC compared with three other groups (head injury without loss of consciousness = 26.1%; motor vehicle accident without head injury = 23%; and control = 17.3%). However, the most salient predictors of PPCSC were early life psychiatric difficulties such as anxiety or depression, limited social support, lower intelligence, and interactions among these variables. The predictive value of loss of consciousness was significant, but low (1.4% of unique variance). The findings provide support for the premise that PPCSC is mediated in part by individual resilience, preexisting psychological status, and psychosocial support.

Accidents, Traffic↗

PubMed2003

Development of the Key Behaviors Change Inventory: a traumatic brain injury behavioral outcome assessment instrument.

OBJECTIVE: To describe the development and initial validation of a neurobehavioral outcome measure, the Key Behaviors Change Inventory (KBCI), for individuals with traumatic brain injury (TBI). DESIGN: Scale construction and development, and validity study. SETTING: Large state university and postal survey. PARTICIPANTS: Seventy-five volunteer undergraduate students and 25 volunteer collateral informants of individuals with TBI participated in the item-analysis phase. Thirty members of the Brain Injury Association and 20 members of the National Multiple Sclerosis Society rated both an identified patient and an age- and gender-equated control in the validation phase. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Content validity was examined through expert panel item sorts. Scale internal consistencies were examined with the Cronbach alpha. Construct validity was examined by comparing scale elevations between controls and 2 neurologic groups. RESULTS: Item-analysis procedures resulted in 8 scales of 8 items each: inattention, impulsivity, unawareness of problems, apathy, interpersonal difficulties, communication problems, somatic difficulties, and emotional adjustment. Internal consistency reliability coefficients ranged from.82 to.91. Multivariate analysis of variance revealed significant (P</=.001) differences in scale elevations among TBI, multiple sclerosis (MS), and control groups. The TBI and MS groups scored significantly higher than the control group on all scales; a subset of KBCI scales discriminated between the 2 neurologic groups. CONCLUSION: The KBCI was both sensitive and specific to typical behavioral changes after TBI, thus supporting its usefulness in rehabilitation settings. Cross-validation and development of a normative database are future steps necessary in its development.

Adaptation, Psychological↗

PubMed2003

Executive and nonexecutive neuropsychological functioning in antisocial personality disorder.

OBJECTIVE: To examine the relationships between antisocial personality disorder and executive abilities as well as antisocial personality disorder with other domains of cognitive functioning. BACKGROUND: Previous research has suggested that antisocial personality disorder is associated with impaired executive functioning. However, methodological limitations of past research have resulted in inconsistent findings. METHODS: Executive functioning and other cognitive abilities were compared in four demographically matched groups of middle-aged community dwelling male veterans (N = 336). The groups were: (A). those with active antisocial personality disorder psychopathology; (B). those with a lifetime prevalence of antisocial personality disorder but inactive antisocial personality disorder psychopathology; (C). a nonantisocial personality disorder psychiatrically matched control group; and (D). a normal control group. RESULTS: Multivariate analysis of variance revealed that the four groups were not statistically significantly different on measures of executive functioning or other cognitive abilities. CONCLUSIONS: Those with antisocial personality disorder perform at comparable levels to psychiatric and normal controls with respect to executive functioning and other domains of cognitive ability (i.e., language, memory, visuospatial, and motor abilities). An incidental finding was that, over time, the antisocial personality disorder groups improved more than control groups on a measure of general intellectual aptitude.

Adult↗

PubMed2002

Effects of alcohol and cigarette use on cognition in middle-aged adults.

In this retrospective cohort study we examined the independent and interactive effects of drinking and smoking on cognition in a sample of 3361 males, ages 31 to 49, with varying lifetime histories of alcohol and cigarette use. Dependent variables were neuropsychological measures of global and specific cognitive abilities. Comparison of the ability scores of seven groups, defined by their drinking and smoking histories, explained only 5.4% of the multivariate variance in cognitive ability and less than 2% in any individual cognitive measure. Regression analyses for current drinkers and smokers showed only a single significant, but negligible, effect of pack-years of smoking on a measure of global cognitive ability. Differences in cognitive function in groups defined by intensity of alcohol and cigarette use revealed no significant effect for drinking and a significant, but very small, effect for smoking.

Adult↗

PubMed2002

Effects of the use of alcohol and cigarettes on cognition in elderly adults.

The objective of this study was to examine the independent and interactive effects of lifetime patterns of drinking and smoking on cognitive performance in the elderly. A sample of 395 individuals with varying histories of alcohol and cigarette use was drawn from the Charlotte County Healthy Aging Study, a community-based, cross-sectional study of randomly selected older adults of age 60 to 84. Dependent variables were the results of a neuropsychological battery that provided measures of general cognitive ability, executive function, and memory. Specifically, we examined (1) differences in performance among groups of abstainers, drinkers, and smokers, (2) the effects of lifetime drinking and smoking dose on cognition within the group of users, and (3) the effects of intensity of drinking and smoking on cognition. Potential methodological confounds, such as age, education, and medical history, were controlled by means of sampling and covariance procedures. Analyses failed to provide evidence for a beneficial J-curve or threshold effect for drinking, but did not reveal any detrimental effect. No detrimental effect of smoking was found in any analysis; nor was there any evidence of an interaction between alcohol and cigarette use on any cognitive measure.

Aged↗

PubMed2002

The Key Behaviors Change Inventory and executive functioning in an elderly clinic sample.

The Key Behaviors Change Inventory (KBCI) was developed to assess executive, behavioral, and emotional functioning following brain insults and to track the course of recovery. The purpose of this study was to investigate, in an elderly memory disorder clinic sample, the convergent and discriminant validity of the KBCI by examining the relationships between various measures of executive functioning and the KBCI scales that theoretically relate to executive functions. The KBCI was administered to the caregivers of 97 consecutive patients who came to a memory disorders clinic seeking services. The KBCI scales of Inattention, Apathy, Unawareness of Problems, and Communication Problems were significantly correlated with cognitive measures of executive functioning but not with measures of memory, visuospatial abilities or global cognitive functioning. In contrast, KBCI scales of Interpersonal Difficulties, Somatic Difficulties, and Emotional Adjustment were not related to any cognitive measures, either executive or nonexecutive. Contrary to predicted findings, the Impulsivity Scale was not associated with cognitive measures of executive functioning. This lack of relationship most likely reflects the failure to include executive measures of orbitofrontal functioning in this study. Results provide convergent and discriminant validity support for the KBCI. The KBCI may be a useful tool for assessing and tracking the executive, behavioral, and emotional sequelae of neurologic disorders.

Adaptation, Psychological↗

PubMed2002

Neuropsychological findings in combat-related posttraumatic stress disorder.

Previous research investigating whether combat-related Posttraumatic Stress Disorder (PTSD) is associated with impaired neuropsychological functioning has yielded inconsistent findings. The present study addressed many methodological limitations of previous research. Neuropsychological measures of intellectual ability, learning, memory, attention, visuospatial ability, executive functioning, language, and psychomotor speed were compared in four groups of early middle-aged community dwelling veterans. The four demographically comparable groups were: (a) those with current PTSD symptoms (n=80); (b) those with a prior history of PTSD but not currently experiencing active PTSD symptoms (n=80); (c) a non-PTSD psychiatrically matched control group (n=80); and (d) a normal control group (n=80). Results indicated that the four groups did not statistically differ on the neuropsychological measures and that veterans with PTSD perform similarly to demographically matched controls. Results further suggested that the cognitive difficulties previously linked to PTSD may actually have been secondary to preexisting individual differences or other clinical conditions coexisting with PTSD.

Adult↗

PubMed2002

Validity indicators within the Wisconsin Card Sorting Test: application of new and previously researched multivariate procedures in multiple traumatic brain injury samples.

The Wisconsin Card Sorting Test (WCST) is a popular neuropsychological measure of executive dysfunction that has been researched with regard to invalid performances, a subset of which in a forensic context could be associated with malingering. In the first of three studies, WCST multivariate approaches identified in prior research (Bernard, McGrath, & Houston, 1996; Suhr & Boyer, 1999), as well as newly created variables, were used to differentiate 33 chronic traumatic brain injury (TBI) patients with good effort and 27 patients with probable insufficient effort (IE). Newly created variables that were derived logically based upon hypotheses regarding strategies that might be employed by malingerers were not effective in differentiating TBI and IE groups. Application of previously researched validity indicators based upon commonly used WCST variables, individually, and within new logistic regression findings were reasonably effective in differentiating TBI and IE groups. In order to determine whether results would vary in different TBI samples, these validity indicators were examined in Study 2 with 75 moderate and severe, acute TBI rehabilitation patients whose posttraumatic amnesia had just resolved. Statistically significant differences were present between the IE group of Study 1 and the rehabilitation patient group of Study 2 on failures to maintain set, number of trials to achieve first correct category, and number of categories completed. All these measures were performed more poorly by the IE group. However, previously used multivariate approaches and the logistic regression analysis developed in Study 1 ranged widely in the degree to which Study 2's more acute rehabilitation patients were correctly classified. Specifically, the discriminant function of Bernard and colleagues correctly classified 73% and the Suhr and Boyer logistic regression correctly classified 75% of the Study 2 participants. The Study 1 logistic regression classified 97% of the Study 2 participants correctly. In Study 3, 130 mild to severe TBI patients in the VA system were studied. The Study 1 IE group performed significantly worse than the more acute and more severe VA TBI group on all 10 common WCST variables of interest. Application of the three multivariate procedures resulted in good to excellent classification rates: Suhr and Boyer logistic regression 85%, Bernard et al. discriminant function 85%, and Study 1 logistic regression 99%. The aggregate discussion of the three studies focuses on apparent differences in samples associated with varying degrees of success in identifying TBI patients. Application of these validity indicators in forensic situations should consider that some of these multivariate approaches possess possible classification limitations associated with chronicity and severity of the reported TBI. Only the Study 1 logistic regression demonstrated improved classification rates with the more acute and severe patients of Study 2 and Study 3. As with all validity indicators, use of any WCST IE criteria in isolation would not be appropriate.

Adult↗

PubMed2002

Differences in executive functioning between Alzheimer's disease and subcortical ischemic vascular dementia.

The present study examined the performance of 114 individuals (62 males, 52 females) on a variety of tests purported to measure executive abilities. Participants were diagnosed with possible or probable Alzheimer's disease (AD), subcortical ischemic vascular dementia (SVaD), or were normal controls (NoDx). Groups were matched for age and education, and clinical groups were matched for severity of dementia. Multivariate and univariate analyses of variance were performed which indicated that the AD and SVaD patients differed from the NoDx on all measures of executive functioning. Further, the AD group made significantly more episodic memory errors than the SVaD group. On the other hand, consistent with previous research, the SVaD group performed significantly better than the AD group on recognition memory, but not on free recall measures. Present findings suggest that AD patients have more executive self-monitoring problems than SVaD patients do, but SVaD patients have more retrieval problems (executive memory search), suggesting a fractionation of executive abilities. Thus, differences between dementia groups depend on the nature of the executive function assessed.

Aged↗

PubMed2002

Identifying retrieval problems using the California Verbal Learning Test.

Wilde, Boake, and Sherer (1995) examined the discrepancy between Long Delayed Free Recall (LDFR) and Recognition Discriminability (RD)--the California Verbal Learning Test (CVLT) index thought to indicate the presence of memory retrieval problems--and found little evidence to recommend its use in traumatic brain injury (TBI). The present investigation re-examined this index from the perspective of a continuum of retrieval deficit severity. CVLT performance was examined in 122 TBI patients, and 2 retrieval deficit indicators of varying severity were evaluated. Memory-impaired control groups were matched with retrieval deficit groups on initial acquisition and demographic characteristics. Individuals with a LDFR/RD discrepancy did not show predicted differences on other CVLT indices of retrieval problems, similar to the findings of Wilde et al. (1995). In contrast, individuals with a consistent discrepancy between free recall and semantic cued recall (Short and Long Delay) had greater improvement with recognition cueing and made fewer intrusive errors than controls. Individuals who benefited from semantic cues (where retrieval of the target word is still required) also benefited from recognition cues (where retrieval demands are minimal). Evidence supported the existence of a continuum of retrieval deficit severity. An LDFR/RD discrepancy without performance improvement from semantic cueing appears to indicate a more severe retrieval deficit, whereas performance improvement from both recognition and semantic cueing indicates less severe retrieval deficits.

Adult↗

PubMed2002

Elderly norms for the Spot-the-Word test.

This study provides population-based normative data for healthy, community-dwelling American elderly on the Spot-the-Word test (STW). The effects of age, education, and gender on STW performance are also investigated. Given previously limited normative data for the elderly, the current norms expand the clinical utility of STW as an estimate of premorbid intelligence. Significant but small effects were found for age on STW performance. Significant and moderate effects were found for education. Therefore, normative adjustments are provided for education. Consistent with previous research, no effect was found for gender.

Journal Article↗

PubMed2002

3MS normative data for the elderly.

The Modified Mini-Mental State Examination (3MS) was developed to overcome shortcomings of the Mini-Mental Status Exam (MMSE), specifically its narrow range of possible scores and ceiling effects. Several studies have examined the psychometric characteristics of the 3MS, showing an improvement in reliability and increased sensitivity in detecting dementia in comparison to the MMSE. Despite research supporting the favorable psychometric features of the 3MS, the clinical value of the instrument is restricted by limited normative data, especially for the elderly population. In this study, we examine the influence of demographic characteristics on 3MS scores and present descriptive data for a sample of 393 community-dwelling older adults. Normative data, based on age and with adjustments for education, are provided for clinical use.

Journal Article↗

PubMed2002

The effects of depression and anxiety on memory performance.

The effects of depression and anxiety, as assessed by MMPI D and Pt scales, on memory performance was examined in 3999 veterans who completed the California Verbal Learning Test (CVLT). Depressive symptoms (without anxiety) had an adverse effect on immediate recall of new information and the total amount (but not rate) of acquisition; however, retrieval and retention were unaffected. On the other hand, high levels of anxiety did not have significant detrimental effects on any aspect of memory functioning assessed including immediate recall, total amount acquired, retention, and retrieval of novel information. However, when depression was compounded by anxiety, there was not only an adverse effect on immediate recall and amount (but not rate) of acquisition, but also on the retrieval of newly learned information. We conclude that the presence of comorbid anxiety may, in part, account for the variability in previous research findings regarding the effects of depression on memory functioning.

Journal Article↗

PubMedDate not supplied

Demographic, medical, and psychiatric factors in work and marital status after mild head injury.

OBJECTIVE: To explore factors associated with long-term outcomes of work and marital status in individuals who had experienced a mild head injury (MHI), as well as those who had not. DESIGN: Population-based study using logistical regression analyses to investigate the impact of preinjury characteristics on work and marital status. PARTICIPANTS: Two groups of Vietnam-era Army veterans: 626 who had experienced a MHI an average of 8 years before examination, and 3,896 who had not. MAIN OUTCOME MEASURES: Demographic characteristics, concurrent medical conditions, early life psychiatric problems, loss of consciousness (LOC), and interactions among these variables were used to predict current work and marital status. RESULTS: Multiple variables were associated with work and marital status in the sample with MHI, accounting for approximately 23% and 17% of the variance in these two outcome variables, respectively. In contrast, the same factors accounted for significantly less variance in outcome in the sample without a head injury-13.3% and 9.4% for work and marital status, respectively. CONCLUSIONS: These findings suggest a more potent role for and increased vulnerability to the influence of demographic, medical, and psychiatric factors on outcomes after a MHI. That is, MHI itself moderates the influence of preinjury characteristics on work and marital status. In addition, in those who had a MHI, moderator relationships were found between education and LOC for both work and marital status. Similarly, complex moderator relationships among race, region of residence, and LOC were found for both work and marital status outcomes.

Adult↗