Leila Glass

Further Development of a Neurobehavioral Profile of Fetal Alcohol Spectrum Disorders

BACKGROUND Heavy prenatal alcohol exposure (AE) results in a broad array of neurobehavioral deficits. Recent research has focused on identification of a neurobehavioral profile or profiles that will improve the identification of children affected by AE. This study aimed to build on our preliminary neurobehavioral profile to improve classification accuracy and test the specificity of the resulting profile in an alternate clinical group. METHODS A standardized neuropsychological test battery was administered to 3 groups of children: subjects with AE (n = 209), typically developing controls (CON, n = 185), and subjects with attention-deficit/hyperactivity disorder (ADHD, n = 74). We assessed a large sample from 6 sites in the United States and South Africa, using standardized methodology. Data were analyzed using 3 latent profile analyses including (i) subjects with fetal alcohol syndrome (FAS) and controls, (ii) subjects with AE without FAS and controls, and (iii) subjects with AE (with or without FAS) and subjects with ADHD. RESULTS Classification accuracy was moderate but significant across the 3 analyses. In analysis 1, overall classification accuracy was 76.1% (77.2% FAS, 75.7% CON). In the second analysis, overall classification accuracy was 71.5% (70.1% AE/non-FAS, 72.4% CON). In the third analysis, overall classification accuracy was 73.9% (59.8% AE, 75.7% ADHD). Subjects that were misclassified were examined for systematic differences from those that were correctly classified. CONCLUSIONS The results of this study indicate that the neuropsychological effects of AE are clinically meaningful and can be used to accurately distinguish alcohol-affected children from both typically developing children and children with ADHD. Further, in combination with other recent studies, these data suggest that approximately 70% of children with heavy prenatal alcohol exposure are neurobehaviorally affected, while the remaining 30% are spared these often-devastating consequences, at least those in the domains under study. Refining the neurobehavioral profile will allow improved identification and treatment development for children affected by prenatal alcohol exposure.

Neuropsychological deficits associated with heavy prenatal alcohol exposure are not exacerbated by ADHD.

OBJECTIVE Neuropsychological functioning of individuals with attention-deficit/hyperactivity disorder (ADHD) or heavy prenatal alcohol exposure has been well documented independently. This study examined the interaction between both factors on cognitive performance in children. METHOD As part of a multisite study, 344 children (8-16 y, M = 12.28, SD = 2.52) completed a comprehensive neuropsychological battery. Four subject groups were tested: children with histories of heavy prenatal alcohol exposure (AE) and ADHD (AE+, n = 90), alcohol-exposed without ADHD, (AE-, n = 38), nonexposed with ADHD (ADHD, n = 80), and nonexposed without ADHD (CON, n = 136). RESULTS Separate 2(AE) × 2(ADHD) MANCOVAs revealed significant main and interactive effects of ADHD and AE on overall WISC-IV, D-KEFS, and CANTAB performance. Individual ANOVAs revealed significant interactions on 2 WISC-IV indices [Verbal Comprehension (VCI), Perceptual Reasoning (PRI)], and four D-KEFS and CANTAB subtests [Design Fluency, Verbal Fluency, Trail Making, Spatial Working Memory]. Follow-up analyses demonstrated no difference between AE+ and AE- groups on these measures. The combined AE+/- group demonstrated more severe impairment than the ADHD group on VCI and PRI, but there were no other differences between clinical groups. CONCLUSIONS These results support a combined AE+/- group for neuropsychological research and indicate that, in some cases, the neuropsychological effects seen in ADHD are altered by prenatal alcohol exposure. The effects of alcohol exposure on verbal comprehension and perceptual reasoning were greater than those related to having ADHD without alcohol exposure, although both conditions independently resulted in cognitive impairment compared to controls. Clinically, these findings demonstrate task-dependent patterns of impairment across clinical disorders.

The clinical utility and specificity of parent report of executive function among children with prenatal alcohol exposure.

Prenatal alcohol exposure and attention-deficit/hyperactivity disorder (ADHD) result in behavioral issues related to poor executive function (EF). This overlap may hinder clinical identification of alcohol-exposed children. This study examined the relation between parent and neuropsychological measures of EF and whether parent ratings aid in differential diagnosis. Neuropsychological measures of EF, including the Delis-Kaplan Executive Function System (D-KEFS), were administered to four groups of children (8-16 years): alcohol-exposed with ADHD (AE+, n=80), alcohol-exposed without ADHD (AE-, n=36), non-exposed with ADHD (ADHD, n=93), and controls (CON, n=167). Primary caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF). For parent ratings, multivariate analyses of variance revealed main effects of Exposure and ADHD and an interaction between these factors, with significant differences between all groups on nearly all BRIEF scales. For neuropsychological measures, results indicated main effects of Exposure and ADHD, but no interaction. Discriminant function analysis indicated the BRIEF accurately classifies groups. These findings confirm compounded behavioral, but not neuropsychological, effects in the AE+ group over the other clinical groups. Parent-report was not correlated with neuropsychological performance in the clinical groups and may provide unique information about neurobehavior. Parent-report measures are clinically useful in predicting alcohol exposure regardless of ADHD. Results contribute to a neurobehavioral profile of prenatal alcohol exposure.

Correspondence of parent report and laboratory measures of inattention and hyperactivity in children with heavy prenatal alcohol exposure.

Clinical research and practice support a multi-method approach to validating behavioral problems in children. We examined whether parent-reported symptoms of hyperactivity and inattention (using the Disruptive Behavior Disorder Rating Scale) were substantiated by objective laboratory measures [hyperactivity measured by wrist-worn actigraphy (ACT) and inattention assessed using a 20-minute continuous performance task (CPT)] in three age- and demographically-matched groups of school-age children: children with prenatal alcohol exposure (AE), non-exposed children with idiopathic ADHD (ADHD), and controls (CON). Results indicated that the clinical groups (AE, ADHD) had significantly higher parent-reported levels for both domains compared to the CON group, and did not differ from each other. On the laboratory measures, the clinical groups were more inattentive than controls on the CPT, but did not differ from each other. In contrast, the ADHD group had higher objective activity on the ACT than AE and CON, which did not differ from each other. Thus, laboratory measures differentially validated parent reports in a group-dependent manner. Actigraphy substantiated parent-reported hyperactivity for children in the ADHD group but not for children in the AE group, while the CPT validated parent-reported inattention for both clinical groups. Although the majority of children in the AE group met the criteria for ADHD, objective activity levels were not different from controls, indicating that hyperactivity may be a less prominent feature in the AE group. Thus, while there is considerable overlap between the effects of prenatal alcohol exposure and ADHD, differences in behavioral profiles may be clinically useful in differential diagnosis. Further, these data indicate that objective measures should be used to validate parent reports.

Anterior cingulate cortex surface area relates to behavioral inhibition in adolescents with and without heavy prenatal alcohol exposure

Prenatal alcohol exposure is associated with behavioral disinhibition, yet the brain structure correlates of this deficit have not been determined with sufficient detail. We examined the hypothesis that the structure of the anterior cingulate cortex (ACC) relates to inhibition performance in youth with histories of heavy prenatal alcohol exposure (AE, n = 32) and non-exposed controls (CON, n = 21). Adolescents (12-17 years) underwent structural magnetic resonance imaging yielding measures of gray matter volume, surface area, and thickness across four ACC subregions. A subset of subjects were administered the NEPSY-II Inhibition subtest. MANCOVA was utilized to test for group differences in ACC and inhibition performance and multiple linear regression was used to probe ACC-inhibition relationships. ACC surface area was significantly smaller in AE, though this effect was primarily driven by reduced right caudal ACC (rcACC). AE also performed significantly worse on inhibition speed but not on inhibition accuracy. Regression analyses with the rcACC revealed a significant group × ACC interaction. A smaller rcACC surface area was associated with slower inhibition completion time for AE but was not significantly associated with inhibition in CON. After accounting for processing speed, smaller rcACC surface area was associated with worse (i.e., slower) inhibition regardless of group. Examining processing speed independently, a decrease in rcACC surface area was associated with faster processing speed for CON but not significantly associated with processing speed in AE. Results support the theory that caudal ACC may monitor reaction time in addition to inhibition and highlight the possibility of delayed ACC neurodevelopment in prenatal alcohol exposure.

Effects of Prenatal Alcohol Exposure and Attention‐Deficit/Hyperactivity Disorder on Adaptive Functioning

BACKGROUND Heavy prenatal alcohol exposure and attention-deficit/hyperactivity disorder (ADHD) are associated with adaptive behavior deficits. This study examined the interaction between these 2 factors on parent ratings of adaptive behavior. METHODS As part of a multisite study, primary caregivers of 317 children (8 to 16 years, M = 12.38) completed the Vineland Adaptive Behavior Scales-Second Edition (VABS-II). Four groups of subjects were included: children with prenatal alcohol exposure with ADHD (AE+, n = 82), children with prenatal alcohol exposure without ADHD (AE-, n = 34), children with ADHD (ADHD, n = 71), and control children (CON, n = 130). VABS-II domain scores (Communication, Daily Living Skills, Socialization) were examined using separate 2 (Alcohol Exposure [AE]) × 2 (ADHD diagnosis) between-subjects analyses of covariance. RESULTS There were significant main effects of AE (p < 0.001) and ADHD (p < 0.001) on all VABS-II domains; alcohol-exposed children had lower scores than children without prenatal alcohol exposure and children with ADHD had lower scores than those without ADHD. There was a significant AE × ADHD interaction effect for Communication, F(1, 308) = 7.49, p = 0.007, partial η(2) = 0.024, but not Daily Living Skills or Socialization domains (ps > 0.27). Follow-up analyses in the Communication domain indicated the effects of ADHD were stronger in comparison subjects (ADHD vs. CON) than exposed subjects (AE+ vs. AE-), and the effects of alcohol exposure were stronger in subjects without ADHD (AE- vs. CON) than in subjects with ADHD (AE+ vs. ADHD) CONCLUSION As found previously, both prenatal alcohol exposure and ADHD increase adaptive behavior deficits in all domains. However, these 2 factors interact to cause the greatest impairment in children with both prenatal alcohol exposure and ADHD for communication abilities. These results further demonstrate the deleterious effects of prenatal alcohol exposure and broaden our understanding of how ADHD exacerbates behavioral outcomes in this population.

Neural signatures of third-party punishment: Evidence from penetrating traumatic brain injury

The ability to survive within a cooperative society depends on impartial third-party punishment (TPP) of social norm violations. Two cognitive mechanisms have been postulated as necessary for the successful completion of TPP: evaluation of legal responsibility and selection of a suitable punishment given the magnitude of the crime. Converging neuroimaging research suggests two supporting domain-general networks; a mentalizing network for evaluation of legal responsibility and a central-executive network for determination of punishment. A whole-brain voxel-based lesion-symptom mapping approach was used in conjunction with a rank-order TPP task to identify brain regions necessary for TPP in a large sample of patients with penetrating traumatic brain injury. Patients who demonstrated atypical TPP had specific lesions in core regions of the mentalizing (dorsomedial prefrontal cortex [PFC], ventromedial PFC) and central-executive (bilateral dorsolateral PFC, right intraparietal sulcus) networks. Altruism and executive functioning (concept formation skills) were significant predictors of TPP: altruism was uniquely associated with TPP in patients with lesions in right dorsolateral PFC and executive functioning was uniquely associated with TPP in individuals with lesions in left PFC. Our findings contribute to the extant literature to support underlying neural networks associated with TPP, with specific brain-behavior causal relationships confirming recent functional neuroimaging research.

Neurobehavioral, neurologic, and neuroimaging characteristics of fetal alcohol spectrum disorders.

Alcohol consumption during pregnancy can have deleterious consequences for the fetus, including changes in central nervous system development leading to permanent neurologic alterations and cognitive and behavioral deficits. Individuals affected by prenatal alcohol exposure, including those with and without fetal alcohol syndrome, are identified under the umbrella of fetal alcohol spectrum disorders (FASD). While studies of humans and animal models confirm that even low to moderate levels of exposure can have detrimental effects, critical doses of such exposure have yet to be specified and the most clinically significant and consistent consequences occur following heavy exposure. These consequences are pervasive, devastating, and can result in long-term dysfunction. This chapter summarizes the neurobehavioral, neurologic, and neuroimaging characteristics of FASD, focusing primarily on clinical research of individuals with histories of heavy prenatal alcohol exposure, although studies of lower levels of exposure, particularly prospective, longitudinal studies, will be discussed where relevant.

Mental Paper Folding Performance Following Penetrating Traumatic Brain Injury in Combat Veterans: A Lesion Mapping Study

Mental paper folding is a complex measure of visuospatial ability involving a coordinated sequence of mental transformations and is often considered a measure of mental ability. The literature is inconclusive regarding the precise neural architecture that underlies performance. We combined the administration of the Armed Forces Qualification Test boxes subtest measuring mental paper folding ability, with a voxel-based lesion symptom mapping approach to identify brain regions associated with impaired mental paper folding ability. Using a large sample of subjects with penetrating traumatic brain injury and defined lesions studied over 2 time points, roughly 15 and 35 years post-injury, enabled us to answer the causal questions regarding mental paper folding impairment. Our results revealed that brain injury significantly exacerbates the decline of performance on mental paper folding tasks over time. Our study adds novel neuropsychological and neuroimaging support for parietal lobe involvement; specifically the right inferior parietal lobule (Broadmanns Area [BA] 40) and the left parahippocampal region (BAs 19, 36). Both areas were consistently associated with mental paper folding performance and demonstrate that the right parietal lobe and the left parahippocampal gyrus play an integral role in mental paper folding tasks.

A Decision Tree to Identify Children Affected by Prenatal Alcohol Exposure

OBJECTIVE To develop and validate a hierarchical decision tree model that combines neurobehavioral and physical measures to identify children affected by prenatal alcohol exposure even when facial dysmorphology is not present. STUDY DESIGN Data were collected as part of a multisite study across the US. The model was developed after we evaluated more than 1000 neurobehavioral and dysmorphology variables collected from 434 children (8-16 years of age) with prenatal alcohol exposure, with and without fetal alcohol syndrome, and nonexposed control subjects, with and without other clinically-relevant behavioral or cognitive concerns. The model subsequently was validated in an independent sample of 454 children in 2 age ranges (5-7 years or 10-16 years). In all analyses, the discriminatory ability of each model step was tested with logistic regression. Classification accuracies and positive and negative predictive values were calculated. RESULTS The model consisted of variables from 4 measures (2 parent questionnaires, an IQ score, and a physical examination). Overall accuracy rates for both the development and validation samples met or exceeded our goal of 80% overall accuracy. CONCLUSIONS The decision tree model distinguished children affected by prenatal alcohol exposure from nonexposed control subjects, including those with other behavioral concerns or conditions. Improving identification of this population will streamline access to clinical services, including multidisciplinary evaluation and treatment.