Executive functioning mediates the link between other neuropsychological domains and daily functioning: a Project FRONTIER study.

BACKGROUND: The purpose of this study was to examine the mediating impact of executive functioning on the link between other neuropsychological domain scores and informant-based rating of functional status. METHODS: Data on 181 participants were analyzed from an ongoing epidemiological study of rural health, Project FRONTIER (mean age = 64.6 ± 13.8 years, 69% women, 42% Mexican American). Executive functioning was assessed by the EXIT25 and other neuropsychological domains were assessed via the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Informant-based rating of functional status was assessed via the Clinical Dementia Rating Scale sum of boxes scores (CDR SB). RESULTS: RBANS Index scores were each significantly (p < 0.05) related to CDR SB scores and EXIT25 scores. EXIT25 score was a significant partial mediator of the link between four RBANS indices (Immediate Memory, Attention, Visuospatial/Construction, Delayed Memory) and CDR SB scores, and a complete mediator of the fifth index (Language). CONCLUSION: Executive functioning is a mediator of the link between other neuropsychological domains and daily functioning. Neuropsychological assessments that do not measure executive functioning will provide only a partial clinical picture with adults and elders.

Identifying functional impairment with scores from the repeatable battery for the assessment of neuropsychological status (RBANS).

OBJECTIVE: To examine the link between RBANS scores and functional impairment. Functional status was evaluated through informant report using the clinical dementia rating (CDR) scale. METHODS: Archival data were reviewed from records of 99 patients in a memory disorder clinic (MDC) research database. Consensus-based diagnoses were Alzheimer's disease (AD; n = 48), mild cognitive impairment (MCI; n = 48), AD with vascular components; (n = 2) and dementia due to psychiatric conditions (n = 1). RESULTS: The RBANS language index score was significantly related to CDR domain scores of community affairs (p < .01), home and hobbies (p < .01), personal care (p < .05), memory (p < 0.01), and judgment (p < 0.01). RBANS immediate memory index scores were significantly related to (p < 0.05) the CDR Memory and judgment and problem solving domains. Based on these findings, follow-up regressions were conducted. Semantic fluency was significantly related to CDR memory (p < 0.01), judgment (p < 0.05), community affairs (p < 0.05), home/hobbies (p < 0.05), and personal care (p < 0.05) functional domains. Picture naming was significantly related to the CDR personal care domain (p < 0.05). List learning was significantly related to CDR memory functional domain (p < 0.01) and judgment (p < 0.05). Lastly, story memory was significantly related to the CDR judgment domain (p < 0.05). CONCLUSIONS: The RBANS may be an indicator of functional impairment as well as a neuropsychological testing tool. The use of the RBANS could reduce the amount of testing that is administered to the patient, or can provide a way to compare other measurements of functional impairment to assess accuracy of findings.

Relation between cognitive testing performance and pattern of substance use in males at treatment entry.

This study examined the frequency and pattern of cognitive impairment in individuals entering substance use disorder treatment and additionally examined the relation between pattern of cognitive impairment and type of substance(s) used: alcohol (n = 116), cocaine (n = 49), alcohol/cocaine (n = 76), and alcohol/multiple substance (n = 54). The Cognistat, a screening measure of cognitive functioning, and the Addiction Severity Index were given to male veterans at the time of entering 3- to 4-week residential/day drug treatment. The most prominent areas of impairment were memory (37% of the total sample) and similarities or abstract concept formation (21% of the total sample). Moderate or greater severity of impairment was noted on at least one Cognistat scale in 35% of the participants. Results indicated no significant differences in the patterns of cognitive domain impairment between groups based on type(s) of substances used at the time of entering treatment. Multiple substance use was significantly related to greater levels of psychiatric problems as identified by the Alcohol Severity Index. Given the rate of impairment in memory and verbal abstract reasoning noted, it is suggested that cognitive screening be a standard consideration in residential substance use disorder treatment to assist in treatment selection and delivery that is optimized to provide maximal benefit to patients.

The California Verbal Learning Test-Children's Version: relation to factor indices of the Wechsler Intelligence Scale for Children-Third Edition.

The California Verbal Learning Test-Children's Version (CVLT-C) provides clinicians with a method of assessing various aspects of children's verbal memory and has been found to be sensitive to memory deficits resulting from a variety of neurological conditions. Intuitively, the CVLT-C would be expected to be highly related to a child's verbal cognitive abilities; however, with only a few exceptions, the relationship of this test to various domains of cognitive function has not been broadly studied empirically. To examine this issue, we evaluated the amount of unique variance in CVLT-C scores that could be predicted by the Verbal Comprehension, Perceptual Organization, Freedom from Distractibility, and Processing Speed indices of the Wechsler Intelligence Scale for Children, Third Edition (WISC-III) beyond that accounted for by age and gender in a sample of 62 children referred to an outpatient psychiatry clinic for neuropsychological evaluation. While the Processing Speed Index predicted a significant amount of variance for both short and long delay free and cued recall, the Verbal Comprehension Index was a poor predictor of CVLT-C performance on all outcome variables, accounting for only 1.5 to 4.5% additional variance above age and gender. These findings indicate that while the CVLT-C may be relatively independent of influences of verbal intelligence and abstract verbal reasoning, general speed and efficiency of processing play an important role in successful encoding for later retrieval on the CVLT-C.

The relation between ethnicity and cognistat performance in males seeking substance use disorder treatment.

This study examined the relation between ethnicity and results obtained during standard administration of the Cognistat, a screening measure of cognitive functioning, in a sample of male veterans seeking substance use disorder treatment (n = 312). Results indicated that screening items for the Naming, Calculation, and Similarities subtests were missed significantly more frequently by African American compared to Caucasian veterans, although the frequency of identification as impaired on the full metric portion of this scales did not differ based on ethnicity. The mean scores on the metric items for these three scales were very similar between groups. Additionally, African American veterans diverted to the Constructional Ability metric items had significantly lower scores on items from that subtest. Logistic regression analyses of impairment identification on the various subtests indicated that ethnicity was a significant (p < .005) predictor beyond the covariates of age and years of education for the Calculation subtest, but only accounted for 4.8% of the variance. Based on the results of the current study, it is recommended that 1) the entire Cognistat be administered regardless of screening item performance to minimize the risk of potential ethnic or cultural based performance bias and 2) a prospective study of potential demographic bias based on comparing Cognistat screening results to a battery of specific neuropsychological assessments of the same constructs be performed to maximize the potential specificity and sensitivity of this assessment for all demographic groups.

The relation of self-report of mood and anxiety to CVLT-C, CVLT, and CVLT-2 in a psychiatric sample.

The relation between mood and cognitive status has been examined extensively over the years suggesting a significant impact of mood and potentially anxiety on memory. This relation is of particular interest to practitioners conducting evaluations in settings that regularly treat individuals diagnosed with psychiatric disorders. With this in mind, the present study sought to evaluate the impact of self-report of depression and anxiety on the California Verbal Learning Test-children's version (CVLT-C), the California Verbal Learning Test (CVLT), and the California Verbal Learning Test-2nd edition (CVLT-2) in a mixed psychiatric sample. Records from 107 patients aged 6-78 evaluated in an outpatient psychiatry unit were examined. Results indicated minimal predictive utility was provided from self-report symptoms of anxiety or depression on CVLT-C, CVLT, or CVLT-2: Trial 1, Trial 5, total score, Short Delay Free Recall, Short Delay Cued Recall, long delay free recall, or long delay cued recall performance above the variance predicted by age, gender, and Full Scale IQ. Additional variance predicted by depression as measured by the Beck Depression Inventory (BDI) and the Child Depression Inventory (CDI) or anxiety as measured by the State-Trait Anxiety Inventory (STAI) was less than 3.0% over that accounted for by the covariates for the great majority of measurements from the various CVLT versions. Exceptions included the CDI that tended to account for approximately 5.0% of the variance on all of the CVLT-C measures and the STAI that accounted for approximately 5.0-10.0% additional variance on the short and long delay measures of the CVLT-2. The present results suggest that performance on the various forms of the CVLT are minimally predicted by self-reported depression and anxiety in a psychiatric setting.

Discrepancies between self-reported years of education and estimated reading level: potential implications for neuropsychologists.

Current standard neuropsychology practice is to examine normative sample performance for systematic influences of demographic variables and then to correct for these influences. The most commonly examined demographic variables are age, gender, and years of education, and current normative databases frequently take these into consideration. However, there is a literature to suggest that self-reported years of educational attainment may not be an accurate reflection of some patients' level of performance and may actually overpredict grade estimates based on reading level. Many of these studies have focused on older samples of individuals who were free of neurological or psychiatric symptoms. In this study, a younger sample (average age = 44.5) of African American (N = 62) and Caucasian (N = 133) patients referred to an outpatient psychiatry unit was examined. Results suggest that the prior findings of a significant discrepancy between self-reported years of education and Wide Range Achievement Test-3rd Edition Reading Recognition performance hold for a younger sample with a broad range of clinical diagnoses. How these findings might influence clinical practice are discussed.

Visual-spatial performance deficits in children with neurofibromatosis type-1.

Neurofibromatosis type-1 (NF1) is a common genetic disorder associated with a variety of medical complications, cognitive impairments, and behavioral problems including a high incidence of Attention Deficit Hyperactivity Disorder (ADHD). The current study examined the hypotheses that deficits in visual-spatial/motor abilities enable one to discriminate and classify children with NF1 (n = 101) compared to control children (n = 37), beyond effects secondary to parent reported ADHD symptomology. Discriminant analysis showed a multivariate combination of visual-spatial/motor ability tests (Judgment of Line Orientation, Block Design subtest of the WISC-III, Recognition-Discrimination Test, Beery Visual-Motor Integration Test) to be a significant predictor of NF1 diagnostic status (P = 0.0000004; canonical R(2) = 0.2306). A significantly greater degree of ADHD behavior was found in the NF1 group, and a discriminant analysis using ADHD residualized visual-spatial motor scores indicated that the combination of tests continued to be a significant predictor of group membership after the level of ADHD behavior was controlled (P = 0.00002 and a canonical R(2) = 0.1818). This combination of tests proved to be a strong discriminator of NF1. It correctly identified 90% of individuals with the diagnosis, and may be useful to educators to provide assistance and alternatives to minimize the impact of learning problems in those with either known or suspected NF1.

Visual-spatial neglect in a child following sub-cortical tumor resection.

Although clinical syndromes of visual-spatial neglect have been well described in adults, clinical features of neglect associated with subcortical dysfunction are infrequently reported in children and have not been described in detail. Unilateral visual-spatial neglect in a 7-year-old male following removal of a right subcortical juvenile pilocytic astrocytoma is reported. Preoperative baseline neurocognitive assessment of the patient established intact attentional and intellectual functioning. Postoperatively visual-spatial neglect was observed that was not accounted for by the patient's visual field deficit. Consistent with classic features of attentional neglect, increases in attentional demands led to greater errors in performance. The risk of unilateral neglect following resection of subcortical tumors that abut the thalamus or disrupt thalamo-cortical projections was confirmed in a retrospective analysis of patients referred for neurocognitive testing at our site. It was concluded that the ventral thalamus may play a role in visual-spatial attention early in development.

Significance of planum temporale and planum parietale morphologic features in neurofibromatosis type 1.

BACKGROUND: Neurofibromatosis type 1 (NF-1) is associated with learning disabilities and cognitive impairment in childhood and adolescence. Individuals with NF-1 have a propensity for brain hyperintensities on T2-weighted magnetic resonance images, macrocephaly, and optic gliomas. Few clear relationships between these central nervous system abnormalities and cognitive function, however, have been found in this population. OBJECTIVES: To determine whether planum temporale (PT) and planum parietale (PP) morphologic features are associated with learning disabilities in NF-1. PATIENTS AND METHODS: We measured and compared the surface area, gray matter volume, and asymmetry of the PT and PP on T1-weighted MRIs from 24 children and adolescents with NF-1 and an equal number of controls. Relationships between these measurements and cognitive and academic achievement scores were examined. RESULTS: The left PT in boys with NF-1 was significantly smaller in both surface area and gray matter volume compared with girls with NF-1 and controls. Boys with NF-1 also showed greater symmetry between the left and right hemispheres in this region compared with girls with NF-1 and controls, who showed a pattern of left greater than right asymmetry of the PT. Intelligence-based discrepancy scores of reading and math achievement, which are commonly used to define learning disabilities, were significantly related to PT asymmetry in the NF-1 group as a whole. Less leftward asymmetry of the PT was associated with poorer reading and math achievement in relation to intellectual test scores. CONCLUSIONS: The high susceptibility of individuals with NF-1 to develop reading and other learning disabilities seems to be related to the development of the sylvian fissure. These results provide further support for the hypothesized association between sylvian fissure morphologic features and learning disabilities.

Caudate nucleus volume asymmetry predicts attention-deficit hyperactivity disorder (ADHD) symptomatology in children.

Clinical diagnosis of attention-deficit hyperactivity disorder (ADHD) is based on evaluation of behavioral functioning in three domains: inattentiveness, hyperactivity, and impulsivity. Caudate and frontal lobe function figures prominently in several neuroanatomic models of attentional functioning. Studies comparing children with and without ADHD have found differences in the size and symmetry of the caudate nuclei. Using multiple regression, we tested the hypothesis that caudate volume symmetry (log left minus log right caudate volume) measured from serial sagittal magnetic resonance images in a sample of nonreferred children (12 girls/15 boys, 7.0 to 16.6 years, 81 to 129 IQ) would predict the cumulative severity of parent-reported ADHD diagnostic behaviors beyond variance predicted by age, sex, and level of internalizing problems as measured by the Child Behavior Checklist. No child had been previously diagnosed with ADHD, although one child was found to meet diagnostic criteria based on the rating scale used for the study. The degree of caudate asymmetry significantly predicted cumulative severity ratings of inattentive behaviors (P = .015), uniquely accounting for 17.1% of the variance in inattention symptomatology over demographic variables and internalizing problems, which collectively predicted 28.9% of the variance. Caudate asymmetry uniquely accounted for only 4.3% of the variance in cumulative severity ratings of hyperactive/impulsive symptomatology over demographic variables and internalizing problems that collectively predicted 21.2% of the variance. A greater degree of right to left caudate volume asymmetry predicted subclinical inattentive behaviors in a sample of nonreferred children. This finding is congruent with neuroanatomic models of attention emphasizing lateralized alteration in prefrontal/striatal systems. The results support the view that clinical ADHD is the extreme of a behavioral continuum that extends into the normal population.