APOE genotype influences acquisition and recall following traumatic brain injury.

APOE has been demonstrated to influence traumatic brain injury (TBI) outcome. The relationship between APOE genotype and memory following TBI was examined in 110 participants in the Defense and Veterans' Head Injury Program. Memory performance was worse in those who had an APOE epsilon 4 allele (n = 30) than those who did not (n = 80), whereas genotype groups did not differ on demographic or injury variables or on measures of executive functioning. These data support a specific role for the APOE protein in memory outcome following TBI, and suggest an APOE isoform-specific effect on neuronal repair processes.

Patterns of verbal learning and memory in traumatic brain injury.

CVLT and WMS-R Digit Span variables were used to calculate indexes of seven specific short- and long-term memory processes: working memory span and central executive functions, and long-term memory encoding, consolidation, retention, retrieval, control abilities. Scores on these indexes were then cluster-analyzed to determine whether subtypes of memory performance exist that correspond to deficits in these theoretical memory constructs. Parallel analyses were conducted with two large samples (N = 150 and N = 151) of individuals who had sustained a traumatic brain injury (TBI). Findings showed that TBI results in subgroups of memory disorders with specific deficits in consolidation, retention, and retrieval processes. Control problems (keeping track of list versus non-list items) only appeared in conjunction with retrieval deficits. Working memory span and central executive functioning (i.e., the ability to manipulate information in working memory) do not appear to be deficits characteristic of TBI as no such clusters emerged in the analyses. By using specific indexes of memory processes, and in contrast to previous studies, patterns of memory dysfunction were found that correspond to deficits in theoretically meaningful memory constructs.

Verbal learning and memory deficits in traumatic brain injury: encoding, consolidation, and retrieval.

The present study examined the nature of verbal memory deficits in individuals with traumatic brain injury (TBI) compared to healthy controls. The study was designed to control for methodological shortcomings of previous related research. Three groups of participants were used: (a) a head injured sample with moderate to severe traumatic brain injuries (N=55), (b) a control sample matched on age and initial performance on CVLT Trial 5 and Sum of Trials 1 to 5 (N=55), and (c) a control sample matched on age, education, and race, but not on initial CVLT learning performance (N=55). Current findings indicate that: (a) rate of learning was comparable across groups, consistent with no encoding differences, (b) TBI patients have a significantly more rapid rate of forgetting of new information than either acquisition-matched or demographic-matched controls, consistent with consolidation problems in TBI, (c) TBI patients have less proactive interference than demographic-matched control participants, consistent with a consolidation problem in the TBI group, (d) TBI patients and acquisition-matched controls have comparably low rates of proactive interference, consistent with impaired acquisition in both of these groups, and (e) TBI patients and controls do not differ in the benefit experienced from semantic or recognition retrieval cues, consistent with no differences in retrieval processes. These data support an impaired consolidation hypothesis, rather than encoding or retrieval deficits, as the primary deficit underlying memory impairment in TBI.

Material-specific memory in traumatic brain injury: differential effects during acquisition, recall, and retention.

Material-specific memory refers to the ability to learn and recall new episodic information on the basis of the nature of the stimulus material (e.g., verbal vs. nonverbal-visuospatial). Structural equation modeling was used to analyze data from a sample of patients with traumatic brain injury to compare 3 models of memory functioning: material-specific, material-specific plus general, and general (non-material-specific). The models were examined separately for acquisition, delayed free recall, and retention aspects of memory. Results suggest that, at least in a population with traumatic brain injury, the acquisition of new information takes place in a material-specific memory fashion, delayed free recall involves both material-specific and general (non-material-specific) memory components, but retention relies primarily on general (non-material-specific) memory processes.

Malingering assessment: evaluation of validity of performance.

Consideration of symptom exaggeration or overt malingering is of particular importance in assessment of alleged mild head trauma and other mild or questionable personal injury situations. Validity is the extent to which tests assess what they were designed to measure. The determination of invalidity is part of the overall neuropsychological interpretation process. In neuropsychology a line of validity assessment research has developed, leading to three general approaches to validity and/or malingering assessment: (a) symptom validity measures, (b) invalid patterns of performance on clinical neuropsychological measures, and (c) concomitant extra-test behavioral information or observations. In each case some aspect of behavior is compared to an external standard or to other intra-subject behavior. Inconsistencies and discrepant comparisons are cause for validity concerns. These approaches are described and recommendations are provided based on the extant literature. However, validity assessment is difficult and at times ambiguous in part because real and feigned deficits are not mutually exclusive. In some clinical situations the most that can be said about an invalid performance is that it is not indicative of the true neurobehavioral capabilities of the person being evaluated, and is not consistent with the presumed etiologic event.

Acute impact of severe traumatic brain injury on family structure and coping responses.

Family stress following traumatic brain injury (TBI) is well documented. Previous studies have shown that family adaptation and the use of coping strategies moderate the stresses of TBI in the long term. However, relatively little is known about the impact on the family and family response during the acute stage of recovery. The present study used Olson's Circumplex Model to examine acute changes in family structure and examined changes in coping responses pre- and post-TBI. Wives of 20 male TBI survivors completed the Couples Version of the Family Adaptability and Cohesion Evaluation Scales-II (FACES-II) and the Coping Responses Inventory (CRI). These questionnaires were completed retrospectively for a stressful event that occurred six months prior to the TBI, then for the current period following the TBI. Results found that 60% of all families experienced a significant change in structure following TBI. As predicted by the Circumplex Model, balanced families changed most, with 70% changing to the extreme type post-TBI. Focus of coping (problem versus emotion) and coping techniques (cognitive versus behavioral) also changed significantly from pre- to post-TBI and differed, depending on post-TBI family structure. Family interventions based on these differences in family structure and coping are presented.

Elderly norms for the Hopkins Verbal Learning Test-Revised.

The present study evaluates the effects of age, education, and gender in a representative sample of older adults and provides normative data for community-dwelling elderly. Age and gender had significant effects on HVLT-R performance. We provide age- and gender-adjusted normative data. Surprisingly, education level did not affect HVLT-R performance, indicating that education-adjusted norms are not necessary for this measure within this age range. We evaluated a subsample of subjects census-matched on age, education, and gender. These subjects did not differ in overall performance from our entire sample. Therefore, the normative data provided in this paper can be considered to be census-comparable for age, education, and gender.

Spot-the-Word: a measure for estimating premorbid intellectual functioning.

The present study investigates the validity of a recently developed measure for estimating premorbid cognitive abilities. The Spot-the-Word Test involves presenting participants with pairs of items comprised of one word and one nonword, and requiring the subject to identify the word. Participants were 61 community-residing healthy older adults ranging in age from 60 to 91 years. Results indicated that education had a small but significant effect on Spot-the-Word performance. However, gender and age did not. Significant correlations were observed between Spot-the-Word scores and scores on other measures used to estimate premorbid abilities, suggesting adequate convergent validity. Furthermore, small and nonsignificant correlations were observed between Spot-the-Word scores and sensitive neuropsychological variables suggesting adequate discriminant validity. Recommendations for future research are discussed.

WAIS-R prediction equations in patients with traumatic brain injury.

Arithmetic algorithms for predicting premorbid Full Scale IQ were evaluated in a sample of 125 brain injured adults who had been evaluated within two months of their injury, and then again one year later. FSIQ at post-test was used as the criterion variable. The prediction equation, based on demographic information only (Barona, Chastain, & Reynolds, 1984), proved to be a modest predictor of premorbid FSIQ. The BEST-3 (Vanderploeg & Schinka, 1995), a prediction equation that incorporates demographic information and performance data, was sensitive to the severity of the brain injury. Subsequent analyses found the BEST-3 to be a better predictor of recovery of function than it was an estimate of premorbid functioning. This study demonstrates the need for flexibility in the interpretation of results, as what was thought to be a prediction equation for premorbid functioning was better viewed as an estimate of recovery.

Comparing methods for estimating premorbid intellectual functioning.

Efforts to determine premorbid intellectual functioning for a patient prior to their current evaluation has been attempted using demographic information, current performance data, or a combination of both. Five of these premorbid intellectual prediction methods were assessed in a sample of 104 neurological patients referred for neuropsychological evaluation and a matched control sample. Predicted Full-Scale Intelligence Quotient (FSIQ) scores of patients did not differ from the true FSIQ scores of the matched controls. Logistic regression analyses found no difference in classification accuracy among the prediction methods. The findings of this study found combined demographic and performance methods developed by Vanderploeg and Schinka (1995), Vanderploeg, Schinka, and Axelrod (1996), Krull, Scott, and Sherer (1995) and Williamson, Krull, and Scott (1996) to be accurate estimates of premorbid functioning. This study found estimates of premorbid functioning based on demographic data alone (Barona, Reynolds, & Chastain, 1984) not to differ from the other methods, which is at odds with prior studies. Prospective studies employing all of these methods are recommended to clarify the utility of demographically based estimates.

Validity of a semantically cued recall procedure for the mini-mental state examination.

OBJECTIVE: The validity of supplementing the three-item recall portion of the Mini-Mental State Examination (MMSE) with a cued recall procedure to help specify the nature of patients' memory problems was examined. METHOD: Subjects were 247 individuals representing three diagnostic groups: Alzheimer's disease (AD), subcortical vascular ischemic dementia (SVaD), and normal controls. Individuals were administered a battery of neuropsychological tests, including the MMSE, as part of a comprehensive evaluation for the presence of dementia or other neurologic disorder. RESULTS: MMSE performance differed among groups. The three-item free recall performance also differed among groups, with post hoc analyses revealing the AD and SVaD groups were more impaired than controls but did not differ significantly from each other. Following a cued recall procedure of the MMSE three-items, groups differed, with post hoc analyses showing that AD patients failed to benefit from cues, whereas SVaD patients performed significantly better and comparable to control subjects. Significant correlations between the MMSE three-item cued recall performance and other memory measures demonstrated concurrent validity. CONCLUSIONS: Consistent with previous research indicating that SVaD is associated with memory encoding and retrieval deficits, whereas AD is associated with consolidation and storage problems, the present study supported the validity of the cued recall procedure of the three items on the MMSE in helping to distinguish between patients with AD and those with a vascular dementia with primarily subcortical pathology; however, despite these findings, a more extensive battery of neuropsychological measures is still recommended to consistently assess subtle diagnostic differences in these memory processes.

Neuropsychological outcomes research: a necessity and an opportunity.

Clinical neuropsychology is subject to the same pressures and demands as other aspects of health care. Increasingly, this means being able to document the usefulness of services and interventions. This special issue of Applied Neuropsychology on neuropsychological outcomes research provides preliminary data on the effectiveness of neuropsychological services in various clinical and medicolegal settings. To date, clinical neuropsychology has devoted little time and energy to such outcomes research. It is hoped that this special issue will challenge neuropsychologists to conduct additional outcomes research that in turn will stimulate the development of increasingly better and more cost-effective services. Such outcomes research is one mark of a maturing and responsible clinical profession.

Normative data on a measure of estimated premorbid abilities as part of a dementia evaluation.

Estimating a person's premorbid cognitive abilities is common practice as part of a dementia assessment. Vocabulary has traditionally served as a "hold" measure because of its relative resilience to neurologic impairment and aging and its high correlation with overall intellectual functioning. Normative data for the Vocabulary subtest of the Shipley Institute of Living Scale (SILS) only go to age 64. This study describes the relations among age, gender, education, and SILS Vocabulary subtest performance. Normative data and Wechsler Adult Intelligence Scale-Revised equivalent Full-Scale IQ scores are reported for SILS Vocabulary subtest performance for a sample of 383 nonimpaired community-dwelling older adults, ranging in age from 60 to 94. Results expand the utility of the Vocabulary subtest of the SILS in providing an estimated level of premorbid cognitive ability.

Profile clusters in the WAIS-R standardization sample.

In this study we applied clustering procedures to a subgroup of 341 participants from the WAIS-R standardization sample. These individuals were selected by virtue of their having full-scale profiles characterized by scatter of greater than 8 scaled scores. Using a hierarchical clustering algorithm, a multistage procedure was used to establish and evaluate a cluster solution. The subject selection and clustering methods were successful in revealing a set of 9 profile types characterized by unique profile shapes. All profiles were associated with FSIQs that were at least in the average range. Seven of the profiles were characterized by specific subtest strengths, only 1 with subtest weaknesses. Examination of the external correlates of profile membership revealed differences among profile groups for age, marital status, education, and occupation. Our findings suggest that variability in and across the 9 profile types in this sample reflects increased contributions of unique abilities in comparison to the influence of the underlying primary and secondary WAIS-R dimensions of cognitive ability.

Predicting WAIS-R IQ premorbid ability: combining subtest performance and demographic variable predictors.

The WAIS-R standardization sample was used to develop regression formulas designed to predict WAIS-R IQ scores. In contrast to previous approaches that focused on either "hold" measures or demographic variables as predictors of premorbid functioning, these two domains were used conjointly in the present study. WAIS-R subtests served as measures of present ability, whereas age, race, sex, education, and occupation served as the demographic predictors. Because any WAIS-R subtest may be impaired following brain injury, no subtest(s) were determined a priori to be "hold" measure(s). Instead, 33 regression formulas were developed each combining 1 of the 11 WAIS-R subtests with demographic variables, to predict IQ scores. The current equations generally doubled the amount of variance accounted for by demographic variables alone and accounted for more variance in WAIS-R IQs than any other currently available method of predicting premorbid cognitive functioning. Regression to the mean was not a significant problem. The regression equations are reported to aid in the estimation of premorbid WAIS-R IQ. Tables of predictive accuracy are also presented.

Relationships between measures of auditory verbal learning and executive functioning.

Relationships between performance on the California Verbal Learning Test (CVLT) and executive abilities were examined. In a sample of 115 neurological cases principal components factor analysis produced five theoretically and clinically meaningful CVLT factors. The five CVLT factors reflected general verbal learning (CVLT1), response discrimination (CVLT2), a proactive interference effect or "working memory" (CVLT3), serial learning strategy (CVLT4), and a retroactive interference effect (CVLT5). Canonical correlation between executive function measures and the five CVLT factor scores yielded one significant canonical variable accounting for 29 percent of the variance in the data. Two CVLT factors (CVLT1 and CVLT3), the Trail Making Test Part B, and Digit Span were significantly correlated with the canonical variate. Higher levels of memory performance were associated with better attention and mental tracking. Based on the present findings, attentional aspects of executive abilities appear to play a role in learning and working memory. Other aspects of executive abilities (abstraction, problem-solving, planning) appear to have minimal relationships with memory processes.

Neuropsychological battery choice and theoretical orientation: a multivariate analysis.

In order to investigate the tests selected by neuropsychologists to make up clinical batteries, a large survey of neuropsychological test usage was cluster analyzed. This provided groupings of tests that are endorsed in common. Theoretical orientation within neuropsychology also was included in the analysis to determine which tests and clusters of tests are more and less associated with the reported orientation of the neuropsychologist. Fifteen clusters of tests were found. Strong and appropriate associations with the eclectic, hypothesis testing, process approach, Halstead-Reitan, Luria, and Benton orientations were seen.

Comparison of the Halstead Category Test and the revised Category Test: comment on Russell and Levy.

Russell and Levy recently published an article describing a new shortened version of the Halstead Category Test. They compared their revised Category Test (RCAT) with the Category Test (CAT) and reported it to be highly correlated with and as accurate as the CAT in predicting the presence or absence of brain damage. However, they substantially modified the CAT and claimed the two versions to be comparable without having administered the RCAT to a single person. This comment critiques their revision from a theoretical perspective and additionally questions the methodology reported by the authors to establish the RCAT's validity. We conclude that the Russell and Levy modifications of the CAT make the RCAT a new, different, and as yet unvalidated instrument. Suggestions are offered for future research in the area of modifying the CAT or its scoring system.

Judgments of emotion in words and faces: ERP correlates.

Visual event-related potentials (ERPs) to two types of stimuli (faces and words) were analyzed to determine the effects of the perceived emotional connotations of the stimuli (positive, neutral, or negative) in 10 right-handed normal functioning adult males. Principal component analysis (PCA) of the ERPs reveals 5 factors accounting for over 90% of the ERP waveform variance for both faces and words. In the facial data, two ERP components varied in amplitude according to the perceived emotional connotation of the stimulus. For the P3 component, neutrally rated stimuli produced significantly larger amplitudes than stimuli rated as positive or negative. This effect was lateralized to the left hemisphere. A later positive component, the slow wave (448-616 ms), manifested complementary effects, i.e. faces perceived as positive and negative produced larger amplitudes than those perceived as neutral over the right hemisphere. The verbal stimuli did not result in significant main effects for perceived emotional connotation, but produced subtle connotation-related differences in slow wave topography. Hemispheric asymmetries, unrelated to affective connotation, were evident in the verbal data, manifesting different patterns of lateralization depending on the ERP component. The results suggest that differential processing of emotional connotation affects ERP waveforms and that the effects can be understood in terms of ERP components known to be associated with more general aspects of cognitive processing.

A reevaluation of the use of the MMPI in the assessment of combat-related posttraumatic stress disorder.

This study attempts to validate previously developed, empirically based Minnesota Multiphasic Personality Inventory (MMPI) decision rules (Keane, Malloy, & Fairbank, 1984) to aid in the diagnosis of combat-related posttraumatic stress disorder (PTSD). Four groups of 21 subjects each were identified: PTSD, psychotic, depressed, and chronic pain. A decision rule based on the standard clinical scales resulted in a correct classification rate (PTSD vs. non-PTSD) of 81% across the four-group sample. An empirically derived MMPI PTSD scale resulted in a correct classification rate of 77%. However, 43% of the PTSD subjects were incorrectly classified as non-PTSD by these rules. Independent, blind sorting of the 84 MMPI profiles by two doctoral-level clinical psychologists resulted in "hit rates" similar to the MMPI decision rules. The present results suggest that the previously derived, empirically based MMPI decision rules for PTSD do scarcely better than chance on correct classification of individuals with PTSD. We suggest that the differential diagnosis of PTSD is difficult because of the wide variety of symptoms in common with other diagnostic groups, and hence the variability of PTSD subjects on psychometric measures. We also suggest that the MMPI decision rules of Keane et al. (1984) may have utility in identifying subgroup(s) of combat-related PTSDs.