Intraindividual neuropsychological test variability in healthy individuals with high average intelligence and educational attainment.

Knowledge of patterns of neuropsychological performance among normal, healthy individuals is integral to the practice of clinical neuropsychology, because clinicians may not always account for intraindividual variability (IIV) before coming to diagnostic conclusions. The IIV was assessed among a sample of 46 healthy individuals with high average intelligence and educational attainment, utilizing a battery of neuropsychological tests, including the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) and Wechsler Memory Scale, Fourth Edition (WMS-IV). The data indicated substantial variability in neurocognitive abilities. All participants were found to demonstrate scores considered impaired by at least 2 standard deviations (SDs). Despite adjusting for outliers, no participant produced a "normal" testing profile with an intraindividual maximum discrepancy (MD) of less than 1 SD in either direction. When WAIS-IV Full Scale IQ (FSIQ) was considered, participants generally demonstrated cognitive test scores ranging from 2 SDs less than to 1.5 SDs greater than their FSIQ. Furthermore, after demographic corrections, the majority (59%) of participants demonstrated at least 1 impaired cognitive test score, as defined by being 1 to 1.5 SDs below the mean. Overall, results substantiate the need for clinicians to consider FSIQ and educational attainment in interpretation of neuropsychological testing results, given the relevant commonality of "abnormal" test scores within this population. This may ultimately reduce the likelihood of making false-positive conclusions of impairment when educational attainment and intelligence are high, thus improving diagnostic accuracy.

Does high scatter on the Wechsler Adult Intelligence Scale-Fourth Edition general ability index reduce validity in predicting Wechsler Memory Scale-Fourth Edition indexes?

We examined whether significant scatter in WAIS-IV GAI will reduce its validity to predict performance on WMS-IV indexes. Participants were 330 individuals with neurological, psychiatric, or neurodevelopmental disorders and 59 referrals who were found to be free of a diagnosable disorder. For VCI > PRI, 59.32% were significant at p < .05 and 12.29% were >22 points. For VCI < PRI, 48.37% were significant at p < .05 and 7.19% were >22 points. Inter-subtest scatter across GAI subtests indicated 82.26% of individuals had a significant scatter range and 13.88% had an unusually large range (≥8). For the VCI, 49.10% had significant scatter (≥3) and 12.08% had an unusually large scatter range (≥5). On the PRI, 43.19% had a significant scatter range (≥4) and 12.85% had an unusually large degree of scatter (≥6). Moderation analyses revealed GAI was a significant predictor of each WMS-IV index. The interaction term of GAI with GAI scatter was not significant for any indexes, indicating that regression equations for predicting WMS-IV scores from GAI did not vary significantly across levels of scatter. Estimation of WMS-IV indexes from the GAI is justified even when significant VCI-PRI discrepancies are present and there is unusual variability across the GAI subtests.

Relative subtest scatter on the WAIS-IV in a clinical sample referred for outpatient neuropsychological evaluation.

OBJECTIVE: The primary aim of this study was to examine relative inter-subtest variability, or scatter, on the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) in a clinical sample of patients referred for neuropsychological evaluation and compare the findings to corresponding data from the scale's standardization sample. METHOD: Participants were 638 individuals diagnosed primarily with neurological, psychiatric, or neurodevelopmental disorders who completed the 10 core subtests of the WAIS-IV as part of a comprehensive assessment battery. RESULTS: Mean participant scores on the WAIS-IV Full Scale IQ and all index composites were within the average range, overall, but were significantly below those of the standardization sample. The correlation between scatter range and highest subtest scaled score was significant, r = .65, indicating a greater degree of subtest scaled score variability in participants with higher than average peak subtest scaled scores than participants with average or below peak subtest scaled scores. Mean variability by highest subtest scaled score was, in most cases, larger in this clinical sample relative to the scale's standardization sample. Exploratory secondary analyses also revealed specific differences in relative scatter based on diagnostic group classification. CONCLUSIONS: Subtest scatter on the WAIS-IV is common among both healthy individuals and clinical patients. Although somewhat higher in this investigation's clinical sample, the significance of this finding generally appears to be of nominal value during interpretation of individual cases but may have some utility in formulating hypotheses when considered in conjunction with reliability data and other approaches for analyzing test scores. High scatter is not pathognomonic of abnormality, and at least some degree of caution is warranted when interpreting subtest scaled score differences on the WAIS-IV.

Distinguishing Alzheimer's disease from vascular dementia: an exploration of five cognitive domains.

The disease process of Alzheimer's disease (AD) and Vascular Dementia (VaD) are dissimilar; however, the cognitive presentations may be difficult to distinguish as they may present in tandem or result in similar deficits despite different pathogenesis. This study examined the efficacy of memory, confrontational naming, visuoconstructional ability, processing speed, and executive functioning in differentiating AD from VaD. Delayed verbal memory, visuoconstructional ability, and confrontational naming as measured by WMS-R Logical Memory II, WAIS-R Block Design (BD), and Boston Naming Test, respectively, were most effective in discriminating between these two disorders. Results indicated AD was best classified by BD, and BD was the most sensitive to AD-related pathogenesis. Delayed memory and confrontational naming were highly implicated in each subtype, suggesting they are sensitive to each disease process, thus reducing the reliability of utilizing them as sole differentiating agents.

Frequency of occurrence of four- and five-factor WAIS-IV profiles.

Interpretive strategies for the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) include Wechsler's four-factor structure and the five-factor Cattell-Horn-Carroll (CHC) model. The frequency of profile occurrence and the contribution of demographic- and ability-related variables to their incidence are unknown. Current participants were 291 referrals (males = 134; female = 157) for neuropsychological evaluation with mean years for age and education of 34.94 (SD = 13.53) and 12.74 (SD = 2.46), respectively. Lichtenberger and Kaufman's guidelines for selecting each model were applied. Of the total, 67.3% were four-factor and 32.6% were five-factor profiles. The same pattern emerged when participants were subdivided by gender, education, ethnicity, IQ, and diagnosis. A noteworthy association between IQ and profile type emerged. When IQ increased, four-factor profiles declined and five-factors increased. A logistic regression, using demographics, IQ, and diagnosis as predictors, correctly classified 64.8% of participants. The average subtest intercorrelations and g saturations in the four-factor group were substantially larger than those for five-factor participants. These findings were consistent with Spearman's differentiation by ability hypothesis.

Self-change: A pathway to cannabis abuse resolution.

Long-term daily cannabis abusers (N = 25) who without treatment stopped using cannabis for at least one year were interviewed about their past substance use, antecedents to change, and factors supportive of change. Respondents' cannabis problems decreased in the year prior to their recovery compared to their lifetime use. Respondents described their successful quit attempts through structured interviews and autobiographical narratives. The narratives were content analyzed for factors related to recovery. The reports indicated that marijuana cessation was motivated more by internal than external factors, and the most common precipitants of quit attempts were cognitive anti-cannabis factors. The major reason reported by respondents for stopping cannabis was a change in how they viewed their cannabis use, followed by negative personal effects. The most common reported maintenance factors were avoidance of situations in which cannabis was used, changes in lifestyle, and the development of non-cannabis-related interests. Cognitive and respiratory functioning were also assessed. Lastly, more than 75% of respondents reported not seeking treatment because they believed it was not needed or because they wanted to quit on their own. Directions for future research are offered.

Improving neuropsychological function after chronic brain injury with hyperbaric oxygen.

PURPOSE: One suggested treatment for chronic brain injury (CBI) is the use of hyperbaric oxygen therapy (HBOT). The present study was an evaluation of neuropsychological improvement after HBOT in CBI patients. METHOD: Study 1 compared test - retest results of 21 CBI children treated with HBOT against test - retest results of 42 untreated brain injured and normal children. Study 2 compared 21 CBI adults treated with HBOT against 42 untreated normal and brain injured adults. In each study, subjects received pre and post assessments to evaluate neuropsychological function. RESULTS: The HBOT-treated children showed significant improvement when compared with the two control groups on measures of daily living, socialization, communication, and motor skills. The treated adults made significant gains in all neuropsychological areas tested as compared to controls. CONCLUSION: The studies were strongly supportive of HBOT as a treatment for lessening the neurological impact of CBI. These studies indicate that HBOT can be an effective aid in ameliorating the neuropsychological and physiological effects of CBI. The absence of a clear sham HBOT treatment group is an issue as it could be that there was a placebo effect, but it should be noted that the controls were receiving more traditional interventions during the study.

Neuropsychological consequences of HIV in children: a review of current literature.

Pediatric HIV has reached epidemic proportions. In 1997, 1.1 million children younger than 15 were living with HIV or AIDS. The virus affects children cognitively and developmentally due to the immaturity of their nervous systems and immune systems. Studies in the area of neuropsychological deficits are as yet limited in number and less well developed than studies on adult HIV. However, despite methodological weaknesses, the literature has proven conclusively that pediatric HIV affects children cognitively, developmentally, emotionally, psychologically, behaviorally, and educationally. Although treatments are allowing these children to live longer, the effects of the virus remain, requiring special care. This review examines the mechanisms behind HIV in children, the neuropsychological findings to date, and the limitations of this work. Possible useful future approaches in understanding the neuropsychological course of the disorder, as well as directions for treatment and prevention are addressed.

Bilingualism, brain injury, and recovery: implications for understanding the bilingual and for therapy.

Psychologists and other therapists are seeing an increasingly large number of bilingual individuals. Such clients are a special challenge when there has been some type of brain injury or disease because of the seemingly unpredictable effect such disorders may have on language skills, impacting either or both of the client's languages and interfering with internal speech that plays a role in higher cognitive functions such as insight and awareness. While there are many clinical assumptions about which language will show the least impairment or recover the best, such suppositions based on clinical lore are often contradictory. A review of the literature finds that the outcome of brain injury may be influenced by factors such as cerebral representation of a secondary language, method of language acquisition, age of acquisition, premorbid language proficiency, and style of learning in an individual. Neuropsychological concepts that can explain these findings are examined, along with their implications for therapy, and rehabilitation.

Abbreviated form of the Wechsler Memory Scale-III Faces subtest.

A major criticism of the Wechsler Memory Scale-III Faces subtest is the number of items, which can be daunting and time-consuming for an impaired client or boring for a normal client. An analysis of several versions, with data from a sample of 50 clinical referrals, revealed that a 32-item subtest was best overall. Using this version, 100% (Faces I) and 94% (Faces II) of the predicted raw scores were less than 4 points away from the actual raw scores, whereas 66% (Faces I) and 70% (Faces II) were less than 2 points away. Limitations of this procedure are discussed.

Relationships of objectively scored Bender variables with MMPI scores in an outpatient psychiatric population.

The purpose of the present study was to examine whether the Advanced Psychodiagnostic Interpretation system for the Bender Gestalt Test could reasonably predict the results of the most widely used objective measure of personality, the MMPI. Despite the widespread use of both tests, no previous studies could be found which correlated actual Bender scores with MMPI results, arising partly from the lack of a well-accepted, reliable, and objective scoring system for the Bender. The study compared the performance of 279 adult psychological outpatients on both the MMPI and Bender. The 55 Bender scorable points, which are seen most frequently in the outpatient population, were factor analyzed to yield 17 factors which were correlated with the MMPI. Significant multiple correlations were found between the Bender factors and 10 of 12 MMPI scales, with significant correlations ranging from .36 to .47. The Bender overall was able to discriminate moderately high scorers on the MMPI from low scorers. The overall results suggested that the Advanced Psychodiagnostic Interpretation scoring system includes measures that reflect general psychopathology and correlate with the MMPI as well as more specific content that is independent of the MMPI scales. The potential of this scoring system and joint use of the MMPI and Bender in personality assessment are discussed. Replication with a larger sample than 279 is encouraged for these 55 Bender and 12 MMPI items.

Cell phone use and visual attention.

The purpose of the present study was to evaluate how much cell phones and just speaking (similar to speaking to someone in the car vs a hands-free cell phone task) interfere with visual attention skills as might be required in a driving situation. Influence of cell phones on attention has been noted but little research has been completed. Licensed adult drivers were divided into three groups (ns = 15) with all subjects taking the Connors Continuous Performance Test II. Group 1 performed without any distractions: those in Group 2 performed with someone in the same room talking to them: Group 3 engaged in a cell phone conversation during the task. Overall, there were substantial differences among groups on all variables, but primarily between the control group and the two experimental groups. While the cell phone group had lower mean scores than the talking group overall, the differences were not significant. Thus, while cell phones were distracting to visual attention functions on the Connors task, they were not more distracting than a similarly active conversation without a cell phone.

Olfactory deficits in frontotemporal dementia as measured by the Alberta Smell Test.

The study of olfaction in neurodegeneration has primarily focused on Alzheimer's disease. Research of olfaction in frontotemporal dementia (FTD) has generally not been empirically studied. The current study compared olfaction in FTD to major depressive disorder (MDD) using the Alberta Smell Test (AST). Independent-samples t test results suggested olfaction in FTD was impaired when compared with participants diagnosed with MDD. The AST Total score (out of 20 trials) significantly predicted the diagnostic group and accounted for 40% of the variance in diagnostic group status with an odds ratio of 20.08. Results suggested that a cutoff of ≤2/20 differentiated FTD from MDD with 94% accuracy (91% sensitivity, 97% specificity) and a cutoff of ≤1/20 differentiated the groups with a 95.5% hit rate (91% sensitivity, 100% specificity). Results confirmed olfactory identification deficits in FTD and suggested that the AST is an effective tool for the demarcation of FTD from MDD. This is especially important due to the potential for significant overlap in the behavioral/emotional phenotype and cognitive deficits between the two disorders when presented with early stages of FTD.

The differential impacts of Alzheimer's dementia, head injury, and stroke on personality dysfunction.

The current study was an attempt to empirically measure and compare the personality effects of Alzheimer's dementia, stroke, and head injury. The study hypothesized that there are differences in the Minnesota Multiphasic Personality Inventory (MMPI-2) patterns generated by the three groups. It was hypothesized that head injury shows the most personality dysfunction. The subjects included 124 stroke clients, 290 head injury clients, and 166 dementia clients. These individuals averaged 58.04 years old, while the mean education was 12.67 years with a minimum of 7 years. The individuals were mostly Caucasian, but included 80 African-Americans, Hispanics, or others. The average chronicity was 77.55 months. The dependent variables were the patient's personality characteristics as measured by 15 MMPI-2 scales. A MANCOVA indicated that there was a significant difference among the three groups after covarying for age, education, and sex (F(30, 1116)=11.03, p<.001). There were overall differences among 10 of the 15 MMPI scales according to univariate follow-up tests. The major pattern was increased pathology for the Head Injury Group. The Stroke and Dementia Groups differed from each other on 6 of the 15 scales but the overall level of severity was similar. High scores on depression and schizophrenia were seen in all three groups. The data appeared to suggest that such factors as the speed of onset of the injury as well as organic factors both played a role in determining personality dysfunction. The elevation on schizophrenia reflected both personality dysfunction as well as a general elevation related to brain injury.

Impact of brain injury severity on personality dysfunction.

Although the cognitive effects of traumatic brain injury (TBI) have been well investigated, emotional problems are less well understood. The purpose of this study was to explore the relationship of the length of loss of consciousness (LOC) and the severity of cognitive impairment (HRNB) to personality changes after head trauma. The subjects included 320 chronic TBI patients. A multivariate analysis was conducted using HRNB (three levels), as measured by a modified Halstead-Reitan Impairment Index and LOC (four levels), as the independent variables, and 30 scales from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) as the dependent variables. Multivariate Fs were significant for both HRNB and LOC. Follow-up ANOVAs and t-tests revealed a consistent pattern of findings across both variables. The data indicated that the reported emotional problems increased with the severity of both LOC and HRNB, except in the most severe groups. The severe subjects when defined by either variable displayed high levels of denial and a lack of awareness of their problems. LOC and HRNB contributed independently to the degree of personality problems, however, LOC was found to be a stronger predictor of personality change than was HRNB at milder levels of severity. The implications of these findings for both treatment and understanding of the mechanisms of head injury are discussed.

Improvement in cerebral metabolism in chronic brain injury after hyperbaric oxygen therapy.

While no research study has yet demonstrated convincing evidence for the efficacy of Hyperbaric Oxygen Therapy (HBOT) in patients with chronic neurological disorders (CND), anecdotal studies have been supportive of its use in improving healing of the damaged brain. The current study hypothesized that (1) individuals with CND show increases in cerebral blood flow and metabolism as measured by Single Positron Emission Computed Tomography (SPECT) in the cerebral hemispheres, but not on measures of cerebellar and pons blood flow; and (2) younger patients show more improvement than older patients. The study used archival data to compare 25 older and 25 younger subjects who were given SPECT scans pretherapy, midtherapy, and posttherapy. ANOVAs using the SPECT scans as a within subjects variable and age as a between subjects variable confirmed the hypothesis that the cerebral measures all changed but that the cerebellar and pons measures did not. Post-hoc t-tests confirmed that there was improvement in blood flow from the beginning to the end of the study. An age effect was found on only two of the five measures; however, there were no interactions. Analysis by post-hoc t-tests showed that the younger group had higher blood flows, but not more improvement than the older group. The results provided the first statistical research data to show the effectiveness of HBOT in improving blood flow in CND. These results indicate that HBOT can be an effective part of the treatment for such clients. The implications of these findings and future research directions were discussed.