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Cognitively impaired older adults may be at increased risk of unsafe driving. Individuals with insight into their own impairments may minimize their risk by restricting or stopping driving. The purpose of this study was to examine the influence of cognitive impairment on driving status and driving habits and intentions. Participants were classified as cognitively impaired, no dementia single (CIND-single), CIND-multiple, or not cognitively impaired (NCI) and compared on their self-reported driving status, habits, and intentions to restrict or quit driving in the future. The groups differed significantly in driving status, but not in whether they restricted their driving or reduced their driving frequency. CIND-multiple group also had significantly higher intention to restrict/stop driving than the NCI group. Reasons for restricting and quitting driving were varied and many individuals reported multiple reasons, both external and internal, for their driving habits and intentions. Regardless of cognitive status, none of the current drivers were seriously thinking of restricting or quitting driving in the next 6 months. It will be important to determine, in future research, how driving practices change over time and what factors influence decisions to restrict or stop driving for people with cognitive impairment.

Although older adults with Mild Cognitive Impairment (MCI) show elevated rates of conversion to dementia as a group, heterogeneity of outcomes is common at the individual level. Using data from a prospective 5-year longitudinal investigation of cognitive change in healthy older adults (N = 262, aged 64-92 years), this study addressed limitations in contemporary MCI identification procedures which rely on single occasion assessment ("Single-Assessment [SA] MCI") by evaluating an alternate operational definition of MCI requiring evidence of persistent cognitive impairment over multiple-testing sessions ("Multiple-Assessment [MA] MCI"). As hypothesized, prevalence of SA-MCI exceeded that of MA-MCI. Further, the MA-MCI groups showed lower baseline cognitive and functional performance and steeper cognitive decline compared with Control and SA-MCI group. Results are discussed with reference to retest effects and clinical implications.

The purpose of the present study was to investigate whether inconsistency in reaction time (RT) is predictive of older adults' ability to solve everyday problems. A sample of 304 community dwelling non-demented older adults, ranging in age from 62 to 92, completed a measure of everyday problem solving, the Everyday Problems Test (EPT). Inconsistency in latencies across trials was assessed on four RT tasks. Performance on the EPT was found to vary according to age and cognitive status. Both mean latencies and inconsistency were significantly associated with EPT performance, such that slower and more inconsistent RTs were associated with poorer everyday problem solving abilities. Even after accounting for age, education, and mean level of performance, inconsistency in reaction time continued to account for a significant proportion of the variance in EPT scores. These findings suggest that indicators of inconsistency in RT may be of functional relevance.

The NEPSY-II consists of 32 subtests for use in a neuropsychological assessment with preschoolers, children, and adolescents. This test review provides an overview of the NEPSY-II for clinicians and researchers, including descriptions of the subtests, changes from the original NEPSY, reliability and validity evidence, strengths, and limitations.

We examined short-term changes in younger and older adults' control beliefs. Participants completed measures of general and memory-specific competence and locus of control on 10 bi-monthly occasions. At each occasion, participants rated their control beliefs prior to and following completion of a battery of cognitive tasks. Exposure to the set of cognitively demanding tasks led to declines in older adults' ratings of both general and memory-specific competence compared to little change or increases in younger adults' ratings. Older adults were also more inconsistent in their reported locus of control beliefs across the 10 occasions. Analyses examining the relationship between control beliefs and actual cognitive performance revealed few significant effects, suggesting that short-term changes in perceived control are not driven by monitoring changes in actual performance. The results suggest the importance of assessing short-term as well as long-term changes in perceived control to obtain a complete picture of aging-related changes.

A well-known challenge for research in the cognitive neuropsychology of aging is to distinguish between the deficits and changes associated with normal aging and those indicative of early cognitive impairment. In a series of 2 studies, the authors explored whether 2 neurocognitive markers, speed (mean level) and inconsistency (intraindividual variability), distinguished between age groups (64-73 and 74-90+ years) and cognitive status groups (nonimpaired, mildly impaired, and moderately impaired). Study 1 (n = 416) showed that both level and inconsistency distinguished between the age and 2 cognitive status (not impaired, mildly impaired) groups, with a modest tendency for inconsistency to predict group membership over and above mean level. Study 2 (n = 304) replicated these results but extended them because of the qualifying effects associated with the unique moderately impaired oldest group. Specifically, not only were the groups more firmly distinguished by both indicators of speed, but evidence for the differential contribution of performance inconsistency was stronger. Neurocognitive markers of speed and inconsistency may be leading indicators of emerging cognitive impairment.

Inconsistency across trials of 2-choice reaction time (RT) data was analyzed in 72 adolescents (age 12-17 years) within 4 groups differentiated by the presence or absence of attention deficit/hyperactivity disorder (ADHD) and reading difficulties (RD). ADHD participants were more inconsistent (across all trials, and in the slow portion of the RT distribution) than controls, but only when RD was present. Within the fast portion of the RT distribution, ADHD participants were more inconsistent than controls regardless of RD. The results highlight the importance of fluctuations in cognitive performance in ADHD and suggest that there may be independent sources of variation in inconsistency affecting the fast and slow portions of the RT distribution.

The individualized nature of the aging process underlines the need to have neuropsychological tests that are sensitive enough to distinguish normal changes associated with aging from those that are pathological. However, these measures are only useful if adequate normative data are available. Normative data are presented for two new executive functioning tasks, the Hayling and Brixton tests, which were administered as part of a neuropsychological battery to 457 typically aging older adults (53-90 years). Advancing age was associated with poorer performance on both the Hayling and Brixton tests. Results showed that fluid intelligence accounts for some but not all of the age-related variance on these tasks.

The authors examined the factor structure of 4 indicators of executive functioning derived from 2 new (i.e., Hayling and Brixton) and 2 traditional (i.e., Stroop and Color Trails) tests. Data were from a cross-sectional sample of 55- to 85-year-old healthy adults (N=427) from the Victoria Longitudinal Study. Confirmatory factor analysis (LISREL 8.52) tested both a 2-factor model of Inhibition (Hayling, Stroop) and Shifting (Brixton, Color Trails) and a single-factor model. The 2-factor model did not fit the data because the covariance matrix of the factors was not positive definite. The single-factor model fit the data well, chi(2)(2, N=427)=0.32, p=.85, root-mean-square error of approximation (RMSEA)=.00, comparative fit index (CFI)=1.00, goodness-of-fit index (GFI)=1.00. Moreover, the single-factor structure of executive functioning was invariant (configural and metric) across gender, and invariant (configural with limited metric) across age. Structural relations showed that poorer executive functioning performance was related to older age and lower fluid intelligence, chi(2)(11, N=418)=23.04, p=.02, RMSEA=.05, CFI=.97, GFI=.98.

Inconsistency in latency across trials of 2-choice reaction time data was analyzed in 273 participants ranging in age from 6 to 81 years. A U-shaped curve defined the relationship between age and inconsistency, with increases in age associated with lower inconsistency throughout childhood and higher inconsistency throughout adulthood. Differences in inconsistency were independent of practice, fatigue, and age-related differences in mean level of performance. Evidence for general and specific variability-producing processes was found in those aged less than 21 years, whereas only a specific process, such as attentional blocks, was evident for those 21 years and older. The findings highlight the importance of considering moment-to-moment changes in performance in psychological research.

This study had two goals. One was to assess whether the WMS-III Spatial Span subtest operates as a visual analogue of Digit Span while the second was to determine whether backward span is a more sensitive measure of working memory than the forward span condition. Analyses based on the WAIS-III-WMS-III standardization and clinical group data revealed some important distinctions between Digit and Spatial Span. The two tasks exhibited differences in patterns of performance on the forward versus backward conditions, in their relationships with age, and in their methodology. Moreover, the backward conditions of both Digit and Spatial Span did not appear more affected by risk factors such as aging or pathology than the forward scores. This runs contrary to the widespread notion that backward span provides differential sensitivity regarding working memory processing.

Victoria Symptom Validity Test (VSVT) scores from six nonlitigants with neurological illness accompanied by dense anterograde amnesia or severe memory impairment are presented. All of these patients obtained perfect or near perfect scores on the VSVT. These data add to the literature suggesting that the VSVT is insensitive to genuine neurologically-based memory impairment and provide an additional floor-level clinical benchmark against which to compare the performance of litigants.

A previous investigation reported that cross-sectional age differences in Digit Symbol Substitution (DSS) test performance reflect declines in perceptual processing speed. Support for the tenability of the processing speed hypothesis requires examining whether longitudinal age-related change in DSS performance is largely mediated by changes in speed. The present study used data from the Victoria Longitudinal Study to examine patterns and predictors of longitudinal change in DSS for 512 older adults (M(age) = 68.37 years, SD = 7.43). On the basis of multilevel modeling, baseline DSS performance was poorer for older participants and men, with longitudinal declines more pronounced with increasing age and decreasing speed. In contrast to the present cross-sectional findings, statistical control of change trajectories in perceptual speed using the same data did not substantially attenuate age changes. These discrepancies suggest different sources of variance may underlie cross-sectional age differences and longitudinal age changes for DSS.

Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions.

The utility of various measures of malingering was evaluated using an analog design in which half the participants (composed of three groups: naive healthy people, professionals working with head-injured people, individuals who suffered a head injury but not currently in litigation) were asked to try their best and the remainder was asked to feign believable injury. Participants were assessed with the Reliable Digit Span (RDS) task, the Victoria Symptom Validity Test (VSVT), and the Computerized Dot Counting Test (CDCT) on three separate occasions in order to determine whether repeat administration of tests improves prediction. The results indicated that regardless of an individual's experience, consideration of both level of performance (particularly on forced-choice symptom validity tasks) and intraindividual variability holds considerable promise for the detection of malingering.

The utility of the WMS–III in detecting lateralized impairment was examined in a large sample of patients with temporal lobe epilepsy. Methods of analysis included evaluation of group means on the various indexes and subtest scores, the use of ROC curves, and an examination of Auditory–Visual Index discrepancy scores. In addition, performance on immediate and delayed indexes in the auditory and the visual modality was compared within each group. Of the WMS–III scores, the Auditory–Visual Delayed Index difference score appeared most sensitive to side of temporal dysfunction, although patient classification rates were not within an acceptable range to have clinical utility. The ability to predict laterality based on statistically significant index score differences was particularly weak for those with left temporal dysfunction. The use of unusually large discrepancies led to improved prediction, however, the rarity of such scores in this population limits their usefulness. Although the utility of the WMS–III in detecting laterality may be limited in preoperative cases, the WMS–III may still hold considerable promise as a measure of memory in documenting baseline performance and in detecting those that may be at risk following surgery. (JINS, 2001, 7, 881–891.)

Symptoms of the Postconcussion Syndrome (PCS) were evaluated in a university sample, using the Postconcussion Syndrome Checklist (PCSC). Three hundred twenty-six participants completed a questionnaire regarding history of head injury, cognitive or psychosocial difficulties, and demographic data. Scores on the PCSC did not vary by self-report of head injury. Females, however, endorsed more frequent, intense, and prolonged symptomatology, regardless of history or severity of head injury. Only 5% of the sample endorsed more than 6 symptoms on the PCSC, suggesting a potentially useful cutoff for abnormality. The PCSC was significantly correlated with the Beck Depression Inventory, suggesting that general level of psychological distress is a key factor in evaluating symptoms of PCS.

Object. The authors sought to determine the impact of early temporal lobectomy (in patients younger than age 17 years) on intellectual functioning. The efficacy of temporal lobectomy for treating seizures is well established and the procedure is becoming more acceptable as a treatment for children whose seizures are intractable. However, cognitive outcomes of temporal lobectomy in children and adolescents are largely unreported. The present study takes advantage of a unique multicenter collaboration to examine retrospectively intellectual functioning in a large sample of children who underwent temporal lobectomy.Methods. Intellectual functioning was assessed before and after temporal lobectomy for treatment of medication-resistant seizures in 82 patients at eight centers of epilepsy surgery. All children underwent standard presurgical examinations, including electroencephalography—video monitoring, magnetic resonance (MR) imaging, and neuropsychological testing, at their respective centers.Forty-three children underwent left temporal lobectomy and 39 underwent right temporal lobectomy. For the entire sample, there were no significant declines in intelligence quotient (IQ) following surgery. Children who underwent left temporal lobectomy demonstrated no significant loss in verbal intellectual functioning and improved significantly in nonverbal intellectual functioning. Children who underwent right temporal lobectomy did not demonstrate significant changes in intellectual functioning. Although group scores showed no change in overall IQ values, an analysis of individual changes revealed that approximately 10% of the sample experienced a significant decline and 9% experienced significant improvement in verbal functioning. Significant improvement in nonverbal cognitive function was observed in 16% of the sample and only 2% of the sample showed significant declines. Risk factors for significant decline included older patient age at the time of surgery and the presence of a structural lesion other than mesial temporal sclerosis on MR imaging.Conclusions. The present study provides preliminary data for establishing the risk of cognitive morbidity posed by temporal lobectomy performed during childhood. With respect to global intellectual functioning, a slight improvement was significantly more likely to occur than a decline. However, there were several patients in whom significant declines did occur. It will be necessary to study further the factors associated with such declines. In addition, further study of more specific cognitive functions, particularly memory, is needed.

The goals of the study were to determine how neuropsychological functioning is related to depressive status in persons with head injury, and to quantify this relationship from a clinically relevant standpoint. Participants were 175 adults involved in litigation, referred for evaluation of suspected head injury. Depression status was measured using the Depression Content (Dep) scale of the MMPI-2. Depression status was related to measures of visual attention and psychomotor skills, but not to other neuropsychological domains such as verbal ability, visual-spatial reasoning, or encoding/organization. However, differences between low Dep and high Dep groups were minimal from a clinical standpoint. Depression appeared to contribute to an increased risk of impaired neuropsychological performance across domains, but only in persons not severely compromised by neuropsychological deficits. Overall, the results indicated a small effect of depression on neuropsychological functioning that is likely only detectable in persons whose neuropsychological compromise is relatively minimal.

The utility of measures for detecting malingering was evaluated using a simulation design in which half the participants were encouraged to do their best and half were asked to feign head injury. Particular attention was focused on the utility of repeated assessment (intraindividual variability) in discriminating the groups. Participants were tested on three occasions on measures commonly used to detect malingering including a specific symptom validity test (SVT). The results indicated that multiple measures of malingering obtained in single assessment (occasion one) discriminated the groups effectively. In addition, however, intraindividual variability in performance, particularly of indicators from the SVT, provided unique information beyond level of performance. The results suggest that response inconsistency across testing sessions may be a clinically useful measure for the detection of malingering.

Summary: Purpose: Considerable debate exists Concerning whether the presence of low preoperative IQ should be a contraindication for focal resective epilepsy surgery. Methods: We examined the relationship between baseline IQ scores and seizure outcome in 1,034 temporal lobectomy cases from eight epilepsy surgery centers participating in the Bozeman Epilepsy Consortium. Results: Those patients who continued to have seizures following surgery had statistically lower preoperative IQ scores than those who were seizure-free (p < 0.009), but only by 2.3 points. This small but statistically significant relationship was fairly robust; it was observed across seven of the eight centers, and indicates that the findings can be generalized. Among patients with IQ scores of ≤75, 32.8% continued to have seizures following surgery, whereas 23.8% and 16.9% were not seizure-free when IQ scores were between 76 and 109 and ≥110, respectively. Relative risk analyses revealed no significant increase in risk among patients with low IQ scores who had no structural lesions other than mesial temporal sclerosis. However, patients with IQ scores of ≤75 had nearly a fourfold (390%) increase in risk for continued seizures as compared with those with higher IQ scores if structural lesions were present. Conclusions: While our results suggest that preoperative IQ scores alone are not good predictors of seizure outcome and should not be used to exclude patients as potential surgical candidates. IQ scores can be useful for counseling patients and their families concerning the relative risks of surgery.

In a descriptive analysis of 158 patients with temporal lobe epilepsy, Taylor (1969) reported that the age of first seizure varied systematically as a function of laterality and sex. We conducted inferential analyses of Taylor's original data which (1) provided support for his proposal of disproportionate left hemisphere vulnerability to seizure onset in early life, but (2) failed to provide evidence of sex differences in age of onset of unilateral seizures. Examination of these effects in a larger sample of 844 patients drawn from the Bozeman Epilepsy Consortium provided some additional support for findings from the inferential analysis. Specifically, the left hemisphere appeared more vulnerable to seizure onset in childhood, this increased vulnerability extending to about age 5 years. Age of onset of seizures was not different when males and females were compared. Thus, reanalysis of Taylor's original data as well as examination of data from a larger, more contemporary sample suggest that seizure onset varies as a function of laterality, but not sex. (JINS, 1997, 3, 428–434.)

The construct of nonverbal memory, as assessed by figural reproduction tests, has recently been questioned by a number of investigators. The purpose of this study was to reexamine this construct and its relationship to right temporal lobe dysfunction. Figural reproduction test scores were examined in 757 epilepsy surgery candidates obtained from 8 epilepsy centers participating in the Bozeman Epilepsy Consortium. All participants exhibited unequivocal evidence of left (LTL) or right (RTL) temporal lobe epilepsy observed in ictal and interictal EEG recordings. All subjects also had IQ scores exceeding 70, right-hand preference, and left hemisphere language dominance confirmed by intracarotid sodium amytal testing. Comparisons of LTL and RTL groups showed no significant differences in scores on the Visual Reproduction subtests from the Wechsler Memory Scale (WMS) or Wechsler Memory Scale–Revised (WMS–R) or on the copy and delayed recall conditions of the Rey–Osterrieth Complex Figure Test (ROCFT). Significant differences were observed among centers on WMS and ROCFT scores, which are likely to be a result of variations in administration and/or scoring procedures. The lack of significant differences between LTL and RTL groups in this large sample raise questions about the nature of nonverbal memory and its relationship to right temporal lobe dysfunction. (JINS, 1997, 3, 435–443.)

There is evidence of a link between stressful life events and risk of cardiovascular disease, but the pathway has not been fully explored. The present study of 1859 employed men tested the association between reported intensity of life events and blood pressure and serum lipid levels, risk behaviors, and psychological distress symptoms. The findings revealed a striking disparity in the outcomes. Life events were negatively associated with systolic (p=0.001) and diastolic (p=0.038) blood pressure, triglycerides (p=0.011), and uric acid (p=0.05), even after controlling for job strain and other possible confounders. In contrast, life events were positively associated with somatic complaints (p

The Five-Point test, a measure of nonverbal figural fluency created by Regard, Strauss, and Knapp (1982), was administered to 258 patients (196 with neurologic disease and 62 with psychiatric disorders) to provide information on the sensitivity of the measure to frontal lobe dysfunction. Patients with frontal lobe dysfunction had a significantly higher percentage of perseverative errors than did nonfrontal neurologic and psychiatric patients on two versions of the Five-Point test. Furthermore, patients with right frontal lobe dysfunction were more often correctly classified as defective on the basis of percent perseveration than patients with cerebral dysfunction in other brain regions. These data provide evidence of the sensitivity of the Five-Point test to brain damage generally and to frontal lobe dysfunction specifically.

The goal of this study was to evaluate the construct and criterion-related validity of the PASAT in 441 adults referred for evaluation of possible closed-head injury (mean age of 32.7 years, SD = 12.4). Convergent evidence for the construct validity of the PASAT as an attention test was stronger than divergent evidence. Although the PASAT correlated with several measures of attention, tests tapping mathematical knowledge accounted for a substantial amount of variance in PASAT scores. Further, other tests measuring conceptually unrelated abilities, such as verbal ability, academic achievement, verbal memory, and complex motor skills were also moderately correlated with PASAT performance. The slower PASAT presentation rate was also related to one test of visual memory and to one test of visual-spatial ability. These results suggest that PASAT performance is related to several cognitive abilities other than attention and processing speed. PASAT scores were not related to criterion-related indices of...

Using the Minnesota Multiphasic Personality Inventory (MMPI), this study investigated preoperative and postoperative emotional and personality adjustment of temporal lobectomy patients from two major epilepsy surgery centers. Temporal lobectomy patients were included only if they were without evidence of lesional pathology on magnetic resonance imaging (MRI; other than evidence of mesial temporal sclerosis), were left-hemisphere language-dominant, and had Wide Range Achievement Test-Revised (WRAT-R) reading achievement standard scores of 70 or higher. The MMPI was completed by 175 patients before and after a temporal lobectomy. There were no significant preoperative differences on any MMPI scale between right temporal (n = 79) and left temporal (n = 96) lobectomy patients. Analysis of MMPI data from one of the surgical centers revealed significant effects for postoperative seizure control. Minimal effects of laterality of seizure onset on preoperative or postoperative psychological adjustment were found. Adequacy of preoperative psychological adjustment and postoperative seizure control have a greater impact on preoperative to postoperative psychological adjustment than side of seizure onset.

Seven subtests from the Wechsler Adult Intelligence Scale, Revised as a Neuropsychological Instrument (WAIS-R NI) were administered to 20 nonreferred university students. The same participants were administered the corresponding subtests from the WAIS-R 3 to 4 weeks later. Data concerning amount and consistency of change in ‘scaled scores’ were compared to those reported by Wechsler (1981) for test-retest with the WAIS-R. Performance on standard items was also compared to performance on multiple choice items from the WAIS-R NI. Gains observed in subtest ‘scaled scores’ at retest were comparable to those reported by Wechsler (1981). A substantial minority of participants obtained lower scores on some multiple choice items than they did on corresponding standard items. Implications and limitations of the current data, and the pressing need for comprehensive normative data for the WAIS-R NI are discussed.

Interhemispheric transfer (IHT) was investigated in patients with multiple sclerosis (n = 20) and healthy control subjects (n = 23). On verbal dichotic listening and tachistoscopic reading tests, MS patients showed a pattern of left-sided suppression and/or right-sided enhancement, consistent with impairment of IHT. Patients with chronic-progressive MS were most affected. Clinical and empirical implications are noted.