Working memory and visuospatial deficits correlate with oculomotor control in children with fetal alcohol spectrum disorder

Brain Volume in Fetal Alcohol Spectrum Disorders Over a 20-Year Span

Importance

Anomalous brain development and mental health problems are prevalent in fetal alcohol spectrum disorders (FASD), but there is a paucity of longitudinal brain imaging research into adulthood. This study presents long-term follow-up of brain volumetrics in a cohort of participants with FASD.

Objective

To test whether brain tissue declines faster with aging in individuals with FASD compared with control participants.

Design, Setting, and Participants

This cohort study used magnetic resonance imaging (MRI) data collected from individuals with FASD and control individuals (age 13-37 years at first magnetic resonance imaging [MRI1] acquired 1997-2000) compared with data collected 20 years later (MRI2; 2018-2021). Participants were recruited for MRI1 through the University of Washington Fetal Alcohol Syndrome (FAS) Follow-Up Study. For MRI2, former participants were recruited by the University of Washington Fetal Alcohol and Drug Unit. Data were analyzed from October 2022 to August 2023.

Main Outcomes and Measures

Intracranial volume (ICV) and regional cortical and cerebellar gray matter, white matter, and cerebrospinal fluid volumes were quantified automatically and analyzed, with group and sex as between-participant factors and age as a within-participant variable.

Results

Of 174 individuals with MRI1 data, 48 refused participation, 36 were unavailable, and 24 could not be located. The remaining 66 individuals (37.9%) were rescanned for MRI2, including 26 controls, 18 individuals with nondysmorphic heavily exposed fetal alcohol effects (FAE; diagnosed prior to MRI1), and 22 individuals with FAS. Mean (SD) age was 22.9 (5.6) years at MRI1 and 44.7 (6.5) years at MRI2, and 35 participants (53%) were male. The FAE and FAS groups exhibited enduring stepped volume deficits at MRI1 and MRI2; volumes among control participants were greater than among participants with FAE, which were greater than volumes among participants with FAS (eg, mean [SD] ICV: control, 1462.3 [119.3] cc at MRI1 and 1465.4 [129.4] cc at MRI2; FAE, 1375.6 [134.1] cc at MRI1 and 1371.7 [120.3] cc at MRI2; FAS, 1297.3 [163.0] cc at MRI1 and 1292.7 [172.1] cc at MRI2), without diagnosis-by-age interactions. Despite these persistent volume deficits, the FAE participants and FAS participants showed patterns of neurodevelopment within reference ranges: increase in white matter and decrease in gray matter of the cortex and decrease in white matter and increase in gray matter of the cerebellum.

Conclusions and Relevance

The findings of this cohort study support a nonaccelerating enduring, brain structural dysmorphic spectrum following prenatal alcohol exposure and a diagnostic distinction based on the degree of dysmorphia. FASD was not a progressive brain structural disorder by middle age, but whether accelerated decline occurs in later years remains to be determined.

Fetal alcohol spectrum disorders (FASD) and youth firesetting: A call on criminal justice, emergency responder, and fire prevention specialists to become informed

Central nervous system damage resulting from prenatal exposure to alcohol, often referred to as fetal alcohol spectrum disorders (FASD), commonly manifests as lacking cognitive functioning, problem solving, impulsivity, memory, executive functioning, and social skill deficits. For individuals with FASD, these brain-based deficits translate into impulsive behaviors and poorly thought-out decision-making, coupled with an inability to anticipate and recognize the sometimes very severe consequences of their behaviors. Not unexpectedly, individuals with FASD frequently find themselves disproportionately involved in the criminal justice system and mental health services. For some individuals with FASD, these behaviors can also include firesetting. First responders, like other health and legal professionals, are often unable to recognize the behavioral indicators of FASD, primarily due to a lack of training. As a result, firesetting behaviors are often attributed to deliberate, willful acts of delinquency, a desire to damage property, thrill seeking, or as attempts for personal gain, rather than being viewed as maladaptive attempts to solve problems by individuals who lack the tools to do this in more appropriate ways. These same skill deficits also present when individuals with FASD are interviewed about their involvement in such behaviors, sometimes resulting in confabulation, suggestibility, and false confessions. Further education and training in FASD are vital for first responders if they are to better support individuals with FASD and minimize their chances of becoming involved in firesetting behaviors. Furthermore, this training and education will help ensure that first responders can intervene in more appropriately when crisis situations do occur. This article will outline key behavioral symptoms of FASD as well as provide first responders with suggestions as to how to best support individuals when FASD is suspected. The brief quote that follows highlights some of the key challenges facing individuals with FASD and how poor decision-making and impulsiveness can result in severe consequences for the individual and those around them.

Screening approaches for identifying fetal alcohol spectrum disorder in children, adolescents, and adults: A systematic review

BACKGROUND

Fetal alcohol spectrum disorder (FASD) is a prevalent neurodevelopmental disorder that is caused by prenatal alcohol exposure (PAE) and associated with a range of cognitive, affective, and health concerns. Although the identification of FASD can facilitate the provision of interventions and support, and plays a protective role against adverse outcomes, there are high rates of missed detection. The identification of FASD via screening may improve its recognition across settings. The current systematic review examined the available evidence on FASD screening tools and approaches across age groups and settings.

METHODS

A systematic search was carried out for both peer-reviewed studies and gray literature sources published between January 1990 and May 2020 and was preregistered with PROSPERO (#CRD42019122077). Studies included in the review focused on human applications of FASD screening in children, adolescents, and adults. The quality of the studies was assessed using the QUADAS-2 and GRADE frameworks.

RESULTS

The search yielded 20 screening tools and approaches across 45 studies, broadly characterized in 2 groups. The first group included approaches currently in use that aim to identify individuals at risk of FASD using a range of markers (n = 19) or associated sentinel dysmorphic facial features (n = 6). Another group of studies, characterized as emerging, focused on identifying promising biomarkers of PAE/FASD (n = 20). Overall, we identified limited research supporting the psychometric properties of most screening approaches. The quality review provided evidence of bias due to the common use of case-control designs and lack of adequate reference standards.

CONCLUSIONS

Although several FASD screening tools and approaches are available for use across a range of age groups and settings, the overall evidence base supporting their psychometric properties is weak, with most studies demonstrating significant risk of bias. Service providers should exercise caution in selecting and implementing FASD screening tools given these limitations. It is critically important to accurately identify individuals with FASD across ages and settings to support healthy outcomes. Thus, there is a pressing need for additional research in this area, particularly validation studies in large and representative samples using robust methodological approaches.

Measurement of neurodevelopmental effects of prenatal alcohol exposure in Ukrainian preschool children

Effects of prenatal alcohol exposure (PAE) are rarely measured in preschool children due to relative insensitivity of assessment methods at this age. To examine the potential of a nonverbal battery in early identification of cognitive problems in alcohol-exposed children, 291 prospectively identified Ukrainian children were evaluated using a test battery focusing on early executive functioning (EF) and visuospatial skills, areas of cognitive development particularly sensitive to PAE in older children. Tests included the Differential Ability Scales, 2^nd Edition (DAS-2) and several NEPSY/NEPSY-II subtests, standardized in the United States. Others were adapted from commonly used non-standardized neuropsychological measures of EF (Preschool Spatial Span, Imitation Hand Game, A not B, Delayed Attention, Subject Ordered Pointing). Children in two sites in Ukraine, Rivne and Khmelnitsky, were tested at 3 ½-4 ½ years to identify effects of PAE. Although most children performed within the average range, Alcohol-Exposed preschoolers had lower scores on DAS-II Summary Scores as well as on specific subtests. To evaluate the effects of alcohol dose during the pre-pregnancy recognition period and during mid-gestation of pregnancy, generalized linear regression models were used controlling for demographic and individual variables. In addition to DAS-II variables, measures reflecting sustained attention, working memory and ability to shift cognitive set were impacted by alcohol dose. Early executive function appears to subsume these performance differences. In conclusion, findings indicate that the effects of PAE can be identified in the preschool period and reliably measured using tests assessing nonverbal and spatial skills supported by executive functioning.

Functional connectivity of the attention networks is altered and relates to neuropsychological outcomes in children with prenatal alcohol exposure

Cognitive and functional brain alterations can occur in children with prenatal alcohol exposure (PAE). We examined the functional connectivity (FC) among regions within and between attention networks, and whether inter- and intranetwork FC moderated cognition in children with PAE (n = 37; age 12.8 ± 2.8 years) and nonexposed controls (n = 40; age 13.2 ± 2.8 years). Participants completed standardized attention and executive functioning tasks and resting state functional MRI. Inter- and intra-network FC and graph-theoretical metrics were calculated among attention network regions. Relative to controls, PAE was associated with reduced FC between the left temporoparietal junction and left ventral frontal cortex and anterior insula/frontal operculum (aI/fO), and between the left intraparietal sulcus and bilateral aI/fO. PAE was associated with increased FC between the right precuneus and intraparietal lobes, the right anterior prefrontal cortex and left ventral frontal cortex and aI/fO, and the left thalamus and dorsal frontal cortex. Graph-theoretical metrics did not differ by group. FC predicted cognitive performance, negatively in the children with PAE and positively in controls. Increased intra-network together with reduced internetwork FC suggests inefficient network specialization and impaired long-range FC among attention network regions after PAE. Results further suggest that those alterations may underlie attention and executive dysfunction in children with PAE.

A review of studies exploring fetal alcohol spectrum disorders through eye tracking measures

The widespread cognitive and cerebral consequences of prenatal alcohol exposure have been established during the last decades, through the exploration of fetal alcohol spectrum disorders (FASD) using neuropsychological and neuroscience tools. This research field has recently benefited from the emergence of innovative measures, among which eye tracking, allowing a precise measure of the eye movements indexing a large range of cognitive functions. We propose a comprehensive review, based on PRISMA guidelines, of the eye tracking studies performed in populations with FASD. Studies were selected from the PsycINFO, PubMed and Scopus databases, and were evaluated through a standardized methodological quality assessment. Studies were classified according to the eye tracking indexes recorded (saccade characteristics, initial fixation, number of fixations, dwell time, gaze pattern) and the process measured (perception, memory, executive functions). Eye tracking data showed that FASD are mostly associated with impaired ocular perceptive/motor abilities (i.e., altered eye movements, centrally for saccade initiation), lower accuracy as well as increased error rates in saccadic eye movements involving working memory abilities, and reduced inhibitory control on saccades. After identifying the main limitations presented by the reviewed studies, we propose guidelines for future research, underlining the need to increase the standardization of diagnosis and evaluation tools, and to improve the methodological quality of eye tracking measures.

Eye Tracking Studies Exploring Cognitive and Affective Processes among Alcohol Drinkers: a Systematic Review and Perspectives

Acute alcohol intoxication and alcohol use disorders are characterized by a wide range of psychological and cerebral impairments, which have been widely explored using neuropsychological and neuroscientific techniques. Eye tracking has recently emerged as an innovative tool to renew this exploration, as eye movements offer complementary information on the processes underlying perceptive, attentional, memory or executive abilities. Building on this, the present systematic and critical literature review provides a comprehensive overview of eye tracking studies exploring cognitive and affective processes among alcohol drinkers. Using PRISMA guidelines, 36 papers that measured eye movements among alcohol drinkers were extracted from three databases (PsycINFO, PubMed, Scopus). They were assessed for methodological quality using a standardized procedure, and categorized based on the main cognitive function measured, namely perceptive abilities, attentional bias, executive function, emotion and prevention/intervention. Eye tracking indexes showed that alcohol-related disorders are related to: (1) a stable pattern of basic eye movement impairments, particularly during alcohol intoxication; (2) a robust attentional bias, indexed by increased dwell times for alcohol-related stimuli; (3) a reduced inhibitory control on saccadic movements; (4) an increased pupillary reactivity to visual stimuli, regardless of their emotional content; (5) a limited visual attention to prevention messages. Perspectives for future research are proposed, notably encouraging the exploration of eye movements in severe alcohol use disorders and the establishment of methodological gold standards for eye tracking measures in this field.

Oculomotor deficits in children adopted from Eastern Europe

AIM

We aim to assess oculomotor behaviour in children adopted from Eastern Europe, who are at high risk of maternal alcohol consumption.

METHODS

This cross-sectional study included 29 adoptees and 29 age-matched controls. All of them underwent a complete ophthalmological examination. Oculomotor control, including fixation and saccadic performance, was assessed using a DIVE device, with eye tracking technology. Anthropometric and facial measurements were obtained from all the adopted children, to identify features of foetal alcohol spectrum disorders (FASD). Fixational and saccadic outcomes were compared between groups, and the effect of adoption and FASD features quantified.

RESULTS

Oculomotor performance was poorer in adopted children. They presented shorter (0.53 vs 1.43 milliseconds in the long task and 0.43 vs 0.82 in the short task) and more unstable fixations (with a bivariate contour ellipse area of 27.9 vs 11.6 degree² during the long task and 6.9 vs 1.3 degree² during the short task) and slower saccadic reactions (278 vs 197 milliseconds). Children with sentinel finding for FASD showed the worst oculomotor outcomes.

CONCLUSION

Children adopted from Eastern Europe present oculomotor deficits, affecting both fixation and saccadic skills. We highlight prenatal exposure to alcohol as the main cause for these deficits.

Relationship Between Task-Based and Parent Report-Based Measures of Attention and Executive Function in Children with Fetal Alcohol Spectrum Disorders (FASD)

A majority of children with fetal alcohol spectrum disorders (FASD) have demonstrated attention and executive function deficits as measured by both parent report measures and performance on tasks requiring sustained levels of attention. However, prior studies have consistently reported a lack of association between parental report-based and task-based performance measures. The current study investigated whether changes in performance over time within-task (i.e., first-half versus second-half) better correspond to parental reports of executive function and temperament in children with FASD. Greater differences in split-half performance during a continuous performance task were found to be associated with higher parent-reported levels of behavioral regulation and inhibitory control. These findings suggest that within-task performance differences may more accurately reflect individual differences in executive function and temperament as measured by parental report and help to further inform the way in which cognitive processes are measured in children with FASD.

Altered Functional Connectivity Observed at Rest in Children and Adolescents Prenatally Exposed to Alcohol

Studies of brain structure in fetal alcohol spectrum disorder (FASD) have shown the global and focal effects that prenatal alcohol exposure (PAE) has on the brain, suggesting but not measuring altered function in FASD. This study aimed to (1) identify resting-state functional networks in children and adolescents with FASD, (2) investigate functional connectivity differences compared with healthy controls, and (3) assess the links to cognitive deficits. Participants included 66 children/adolescents with FASD (aged 5.5-18.9 years) and 67 healthy controls (aged 5.8-18.5 years) scanned across four sites as part of the NeuroDevNet study. Six core functional networks with 27 regions of interest (ROIs) were examined using seed-based and ROI-to-ROI analyses. Average seed-based connectivity maps showed significant spatial overlap of positively correlated regions for all six core networks between FASD and controls, but there was less overlap for negatively correlated regions. ROI-to-ROI matrices demonstrated lower internetwork connectivity between regions primarily associated with the salience network (anterior cingulate cortex and bilateral insula), frontal-parietal network (bilateral posterior parietal cortex), and language network (right posterior superior temporal gyrus). Post hoc correlations of the FASD participants without medication revealed a relationship between functional connectivity and performance on two cognitive tests associated with mathematics ability and attention. Even though participants with PAE exhibit very similar intranetwork functional connectivity patterns as controls, their lower internetwork functional connectivity suggests underlying deficits in the functional network brain architecture that may be related to cognitive impairment.

Myelin Water Fraction Imaging of the Brain in Children with Prenatal Alcohol Exposure

BACKGROUND

Prenatal alcohol exposure (PAE) is linked to alterations of cerebral white matter, including volume and nonspecific diffusion magnetic resonance imaging (MRI) indices of microstructure in humans. Some animal models of PAE have demonstrated myelination deficiencies, but myelin levels have not yet been evaluated in individuals with PAE. Multiecho T₂ MRI offers a quantitative method to estimate myelin water fraction (MWF; related to myelin content) noninvasively, which was used here to evaluate brain myelination in children with PAE.

METHODS

Participants with PAE (n = 10, 6 females, mean age 13.9 years, range 7 to 18 years) and controls (n = 14, 11 females, mean age 13.2 years, range 9 to 16 years) underwent 3T MRI of the brain. T₂ images (15 minutes acquisition for 32 echoes) were used to create MWF maps from which mean MWF was measured in 12 regions of interest (ROIs) including 8 in white matter and 4 in deep gray matter.

RESULTS

As expected, across the combined sample, MWF was highest for major white matter tracts such as the internal capsule and genu/splenium of the corpus callosum (10 to 18%) while the caudate and putamen had MWF less than 5%. Mean MWF was similar across 11/12 brain white and gray matter regions for the PAE and control groups (L/R internal capsule, major forceps, putamen, caudate nucleus, L minor forceps, genu and splenium of corpus callosum). In the PAE group, MWF was positively correlated with age in the genu of corpus callosum and right minor forceps, notably 2 frontal tracts.

CONCLUSIONS

Given comparable MRI-derived myelination fraction measures in PAE relative to controls, white matter alterations shown in other imaging studies, such as diffusion tensor imaging, may reflect microstructural anomalies related to axon caliber and density.

Detection of Children/Youth With Fetal Alcohol Spectrum Disorder Through Eye Movement, Psychometric, and Neuroimaging Data

Background: Fetal alcohol spectrum disorders (FASD) is one of the most common causes of developmental disabilities and neurobehavioral deficits. Despite the high-prevalence of FASD, the current diagnostic process is challenging and time- and money- consuming, with underreported profiles of the neurocognitive and neurobehavioral impairments because of limited clinical capacity. We assessed children/youth with FASD from a multimodal perspective and developed a high-performing, low-cost screening protocol using a machine learning framework. Methods and Findings: Participants with FASD and age-matched typically developing controls completed up to six assessments, including saccadic eye movement tasks (prosaccade, antisaccade, and memory-guided saccade), free viewing of videos, psychometric tests, and neuroimaging of the corpus callosum. We comparatively investigated new machine learning methods applied to these data, toward the acquisition of a quantitative signature of the neurodevelopmental deficits, and the development of an objective, high-throughput screening tool to identify children/youth with FASD. Our method provides a comprehensive profile of distinct measures in domains including sensorimotor and visuospatial control, visual perception, attention, inhibition, working memory, academic functions, and brain structure. We also showed that a combination of four to six assessments yields the best FASD vs. control classification accuracy; however, this protocol is expensive and time consuming. We conducted a cost/benefit analysis of the six assessments and developed a high-performing, low-cost screening protocol based on a subset of eye movement and psychometric tests that approached the best result under a range of constraints (time, cost, participant age, required administration, and access to neuroimaging facility). Using insights from the theory of value of information, we proposed an optimal annual screening procedure for children at risk of FASD. Conclusions: We developed a high-capacity, low-cost screening procedure under constrains, with high expected monetary benefit, substantial impact of the referral and diagnostic process, and expected maximized long-term benefits to the tested individuals and to society. This annual screening procedure for children/youth at risk of FASD can be easily and widely deployed for early identification, potentially leading to earlier intervention and treatment. This is crucial for neurodevelopmental disorders, to mitigate the severity of the disorder and/or frequency of secondary comorbidities.

White matter microstructure in fetal alcohol spectrum disorders: A systematic review of diffusion tensor imaging studies

Diffusion tensor imaging (DTI) has revolutionized our understanding of the neural underpinnings of alcohol teratogenesis. This technique can detect alterations in white matter in neurodevelopmental disorders, such as fetal alcohol spectrum disorder (FASD). Using Prisma guidelines, we identified 23 DTI studies conducted on individuals with prenatal alcohol exposure (PAE). These studies confirm the widespread nature of brain damage in PAE by reporting diffusivity alterations in commissural, association, and projection fibers; and in relation to increasing cognitive impairment. Reduced integrity in terms of lower fractional anisotropy (FA) and higher mean diffusivity (MD) and radial diffusivity (RD) is reported more consistently in the corpus callosum, cerebellar peduncles, cingulum, and longitudinal fasciculi connecting frontal and temporoparietal regions. Although these interesting results provide insight into FASD neuropathology, it is important to investigate the clinical diversity of this disorder for better treatment options and prediction of progression. The aim of this review is to provide a summary of different patterns of neural structure between PAE and typically developed individuals. We further discuss the association of alterations in diffusivity with demographic features and symptomatology of PAE. With the accumulated knowledge of the neural correlates of FASD presenting symptoms, a comprehensive understanding of the heterogeneity in FASD will potentially improve the disease management and will highlight the diagnostic challenges and potential areas of future research avenues, where neural markers may be beneficial.

A better approach to in vivo developmental neurotoxicity assessment: Alignment of rodent testing with effects seen in children after neurotoxic exposures

High throughput screens for developmental neurotoxicity (DN) will facilitate evaluation of chemicals and can be used to prioritize those designated for follow-up. DN is evaluated under different guidelines. Those for drugs generally include peri- and postnatal studies and juvenile toxicity studies. For pesticides and commercial chemicals, when triggered, include developmental neurotoxicity studies (DNT) and extended one-generation reproductive toxicity studies. Raffaele et al. (2010) reviewed 69 pesticide DNT studies and found two of the four behavioral tests underperformed. There are now many epidemiological studies on children showing adverse neurocognitive effects, yet guideline DN studies fail to assess most of the functions affected in children; nor do DN guidelines reflect the advances in brain structure-function relationships from neuroscience. By reducing the number of test ages, removing underperforming tests and replacing them with tests that assess cognitive abilities relevant to children, the value of DN protocols can be improved. Testing for the brain networks that mediate higher cognitive functions need to include assessments of working memory, attention, long-term memory (explicit, implicit, and emotional), and executive functions such as cognitive flexibility. The current DNT focus on what can be measured should be replaced with what should be measured. With the wealth of data available from human studies and neuroscience, the recommendation is made for changes to make DN studies better focused on human-relevant functions using tests of proven validity that assess comparable functions to tests used in children. Such changes will provide regulatory authorities with more relevant data.

Resting-state functional connectivity in children born from gestations complicated by preeclampsia: A pilot study cohort

BACKGROUND

Individuals (PE-F1s) born from preeclampsia (PE)-complicated pregnancies have elevated risks for cognitive impairment. Intervals of disturbed maternal plasma angiokines precede clinical signs of PE. We hypothesized pan-blastocyst dysregulation of angiokines underlies altered PE-F1 brain vascular and neurological development. This could alter brain functional connectivity (FC) patterns at rest.

MATERIALS AND METHODS

Resting-state functional MRI datasets of ten, matched child pairs (5 boys and 5 girls aged 7-10 years of age) from PE or control pregnancies were available for study. Seed-based analysis and independent component analysis (ICA) methodologies were used to assess whether differences in resting-state functional connectivity (rs-FC) were present between PE-F1s and controls. Bilateral amygdala, bilateral hippocampus, and medial prefrontal cortex (MPFC) were selected as regions of interest (ROI) for the seed-based analysis based on previous imaging differences that we reported in this set of children.

RESULTS

Compared to controls, PE-F1 children had increased rs-FC between the right amygdala and left frontal pole, the left amygdala and bilateral frontal pole, and the MPFC and precuneus. PE-F1 children additionally had decreased rs-FC between the MPFC and the left occipital fusiform gyrus compared to controls.

CONCLUSION

These are the first reported rs-FC data for PE-F1s of any age. Theysuggest that PE alters FC during human fetal brain development. Altered FC may contribute to the behavioural and neurological alterations reported in PE-F1s. Longitudinal MRI studies with larger sample sizes are required to confirm these novel findings.

Oculomotor rehabilitation in children with dyslexia

Background: Dyslexia is the most common learning disorder. Visual and oculomotor deficits in dyslexic children have been reported. The purpose of this study was to measure oculomotor parameters and analyze the effect of oculomotor rehabilitation strategies on dyslexia. Methods: Binocular eye movements were recorded by oculomotor subtype of videonystagmography (VNG) testing on 30 children with dyslexia and 20 typical reader children (aged 8-12) in both genders. Dyslexic children were diagnosed with DSM-V scale by experts in reading disorder centers. We studied those children with developmental dyslexia, who had deficits in eye movements recording. Dyslexic children were divided into 2 groups of case and control. Oculomotor rehabilitation (including fixation, saccade, and tracking training) was performed in case group for 1 hour, twice weekly for 8 weeks. Before the intervention, results of oculomotor tests were compared between 3 groups (healthy, case, and control). Then, to analyze the effect of the intervention, results of oculomotor tests were compared between case and control groups in pre- and post- intervention stage. Data were analyzed by independent and paired samples t tests, ANOVA, and repeated measures tests in SPSS v. 21. Results: There were significant differences in oculomotor characteristics of dyslexic children in comparison with those reported in typical children. Oculomotor rehabilitation intervention had a positive effect on improvement of oculomotor responses and eye movements in dyslexic children. Moreover, there was no statistically significant difference between dyslexic children and non-dyslexic children in oculomotor skills after the training. Conclusion: Our results showed the positive effects of oculomotor rehabilitation on eye movements. Primary oculomotor assessment in dyslexic children and early use of oculomotor rehabilitation combined with other treatments are highly recommended.

Altered functional connectivity during spatial working memory in children with heavy prenatal alcohol exposure

Individuals prenatally exposed to alcohol often have impaired spatial working memory (SWM). This study examines functional connections of frontal and parietal regions that support SWM in children with and without prenatal alcohol exposure. Children ages 10 to 16 with histories of heavy prenatal alcohol exposure (AE group; n = 18) and controls (CON group; n = 19) underwent functional magnetic resonance imaging (fMRI) while performing a SWM task. Whole brain task-related functional connectivity of bilateral dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex (PPC) seed regions were estimated for each participant using a psychophysiological interaction approach. Children in the AE group were less accurate than children in the CON group when performing the SWM task (p = 0.008). Positive coupling between bilateral DLPFC seeds and regions within the fronto-parietal network was observed in the CON group, whereas the AE group showed negative connectivity. In contrast to the CON group, the AE group showed positive connectivity between PPC seeds and frontal lobe regions. Across seeds, decreased negative coupling with regions outside the fronto-parietal network (e.g., left middle occipital gyrus) were observed in the AE group relative to the CON group. Functional data clusters were considered significant at p < 0.05. Overall findings suggest that localized alterations in neural activity, aberrant fronto-parietal network synchrony, and poor coordination of neural responses with regions outside of this network may help explain SWM deficits in individuals with a history of heavy prenatal alcohol exposure.

Choline and Working Memory Training Improve Cognitive Deficits Caused by Prenatal Exposure to Ethanol

Prenatal ethanol exposure is associated with deficits in executive function such as working memory, reversal learning and attentional set shifting in humans and animals. These behaviors are dependent on normal structure and function in cholinergic brain regions. Supplementation with choline can improve many behaviors in rodent models of fetal alcohol spectrum disorders and also improves working memory function in normal rats. We tested the hypothesis that supplementation with choline in the postnatal period will improve working memory during adolescence in normal and ethanol-exposed animals, and that working memory engagement during adolescence will transfer to other cognitive domains and have lasting effects on executive function in adulthood. Male and female offspring of rats fed an ethanol-containing liquid diet (ET; 3% v/v) or control dams given a non-ethanol liquid diet (CT) were injected with choline (Cho; 100 mg/kg) or saline (Sal) once per day from postnatal day (P) 16–P30. Animals were trained/tested on a working memory test in adolescence and then underwent attentional set shifting and reversal learning in young adulthood. In adolescence, ET rats required more training to reach criterion than CT-Sal. Choline improved working memory performance for both CT and ET animals. In young adulthood, ET animals also performed poorly on the set shifting and reversal tasks. Deficits were more robust in ET male rats than female ET rats, but Cho improved performance in both sexes. ET male rats given a combination of Cho and working memory training in adolescence required significantly fewer trials to achieve criterion than any other ET group, suggesting that early interventions can cause a persistent improvement.

Long-term alterations to DNA methylation as a biomarker of prenatal alcohol exposure: From mouse models to human children with fetal alcohol spectrum disorders

Rodent models of Fetal Alcohol Spectrum Disorders (FASD) have revealed that prenatal alcohol exposure (PAE) results in differential DNA cytosine methylation in the developing brain. The resulting genome-wide methylation changes are enriched in genes with neurodevelopmental functions. The profile of differential methylation is dynamic and present in some form for life. The methylation changes are transmitted across subsequent mitotic divisions, where they are maintained and further modified over time. More recent follow up has identified a profile of the differential methylation in the buccal swabs of young children born with FASD. While distinct from the profile observed in brain tissue from rodent models, there are similarities. These include changes in genes belonging to a number of neurodevelopmental and behavioral pathways. Specifically, there is increased methylation at the clustered protocadherin genes and deregulation of genomically imprinted genes, even though no single gene is affected in all patients studied to date. These novel results suggest further development of a methylation based strategy could enable early and accurate diagnostics and therapeutics, which have remained a challenge in FASD research. There are two aspects of this challenge that must be addressed in the immediate future: First, the long-term differential methylomics observed in rodent models must be functionally confirmed. Second, the similarities in differential methylation must be further established in humans at a methylomic level and overcome a number of technical limitations. While a cure for FASD is challenging, there is an opportunity for the development of early diagnostics and attenuations towards a higher quality of life.

Fetale Alkoholspektrumstörungen – Diagnose, neuropsychologische Testung und symptomorientierte Förderung

Zusammenfassung. Laut den aktuellen Studien zur Gesundheit in Deutschland (GEDA) haben knapp 20 % der schwangeren Frauen einen „moderaten Alkoholkonsum“ und knapp 8 % einen riskanten Alkoholkonsum. 12 % der Schwangeren geben ein Rauschtrinken (≥ 5 Getränke pro Gelegenheit) seltener als einmal pro Monat, knapp 4 % jeden Monat und 0.1 % mindestens jede Woche an. Zurückhaltende, strenge Schätzungen ergeben, dass ca. 1 % aller Kinder intrauterin durch Alkohol geschädigt werden. Extrapoliert aus dieser Schätzung bedeutet dies, dass in Deutschland ca. 0.8 Millionen Menschen, davon 130 000 Kinder, mit einer Fetalen Alkoholspektrumstörung (FASD) leben. Die Mehrzahl der betroffenen Kinder werden nicht oder erst spät richtig diagnostiziert. Professionelle Helfer im Gesundheits- und Sozialsystem sind bislang über die Symptome und die notwendige Diagnostik der FASD nur unzureichend informiert. Ziel dieses Übersichtsartikels ist die Erläuterung der ärztlichen und psychologischen diagnostischen Möglichkeiten und Notwendigkeiten bei Kindern und Jugendlichen mit FASD. Eine frühzeitige Diagnose und ein konstantes förderndes und gewaltfreies Umfeld sind als wichtigste protektive Faktoren für den Langzeit-Outcome von Menschen mit FASD identifiziert worden.

The Structure of Working Memory in Young Children and Its Relation to Intelligence

This study investigated the structure of working memory in young school-age children by testing the fit of three competing theoretical models using a wide variety of tasks. The best fitting models were then used to assess the relationship between working memory and nonverbal measures of fluid reasoning (Gf) and visual processing (Gv) intelligence. One hundred sixty-eight English-speaking 7-9 year olds with typical development, from three states, participated. Results showed that Cowan's three-factor embedded processes model fit the data slightly better than Baddeley and Hitch's (1974) three-factor model (specified according to Baddeley, 1986) and decisively better than Baddeley's (2000) four-factor model that included an episodic buffer. The focus of attention factor in Cowan's model was a significant predictor of Gf and Gv. The results suggest that the focus of attention, rather than storage, drives the relationship between working memory, Gf, and Gv in young school-age children. Our results do not rule out the Baddeley and Hitch model, but they place constraints on both it and Cowan's model. A common attentional component is needed for feature binding, running digit span, and visual short-term memory tasks; phonological storage is separate, as is a component of central executive processing involved in task manipulation. The results contribute to a zeitgeist in which working memory models are coming together on common ground (cf. Cowan, Saults, & Blume, 2014; Hu, Allen, Baddeley, & Hitch, 2016).

Fetal Alcohol Spectrum Disorders: A Case Study

This grand rounds manuscript reviews important considerations in developing case conceptualizations for individuals with a history of prenatal alcohol exposure. This case study provides an introduction to fetal alcohol spectrum disorders, diagnostic issues, a detailed description of the individual's history, presenting symptoms, neuropsychological test results, and an integrated summary. We describe a 9-year old girl diagnosed with a fetal alcohol spectrum disorder (FASD): Neurobehavioral Disorder Associated with Prenatal Alcohol Exposure (ND-PAE). This patient is a composite of a prototypical child who participated as part of a research project at the Center for Behavioral Teratology who was subsequently seen at an outpatient child psychiatry facility.

Diffusion tensor imaging of white matter and correlates to eye movement control and psychometric testing in children with prenatal alcohol exposure

Prenatal alcohol exposure (PAE) can cause central nervous system dysfunction and widespread structural anomalies as detected by magnetic resonance imaging (MRI). This study focused on diffusion tensor imaging (DTI) of white matter in a large sample of PAE participants that allowed us to examine correlations with behavioral outcomes. Participants were confirmed PAE (n = 69, mean age = 12.5 ± 3.2 years) or typically developing control children (n = 67, mean age = 12.1 ± 3.2 years) who underwent brain MRI, eye movement tasks, and psychometric tests. A semi-automated tractography method extracted fractional anisotropy (FA) and mean diffusivity (MD) values from 15 white matter tracts. The PAE group displayed decreased FA compared with controls in multiple tracts including 3 corpus callosum regions, right corticospinal tract, and 3 left hemisphere tracts connecting to the frontal lobe (cingulum, uncinate fasciculus, and superior longitudinal fasciculus). Significant group by sex interactions were found for the genu, left superior longitudinal fasciculus, and the left uncinate, with females in the PAE group exhibiting lower FA compared with control females. Correlations were found between DTI and eye movement measures in the control group, but these same relationships were absent in the PAE group. In contrast, no correlations were found between DTI and any of the psychometric tests used in this study. These findings support the hypothesis that measures of eye movement control may be valuable functional biomarkers of the brain injury induced by PAE as these tasks reveal group differences that appear to be linked to deficits in white matter integrity in the brain. Hum Brain Mapp 38:444-456, 2017. © 2016 Wiley Periodicals, Inc.

Impact of preeclampsia on cognitive function in the offspring

Preeclampsia (PE) is a significant clinical disorder occurring in 3-5% of all human pregnancies. Offspring of PE pregnancies (PE-F1s) are reported to exhibit greater cognitive impairment than offspring from uncomplicated pregnancies. Previous studies of PE-F1 cognitive ability used tests with bias that do not assess specific cognitive domains. To improve cognitive impairment classification in PE-F1s we used standardized clinical psychometric testing and eye tracking studies of saccadic eye movements. PE-F1s (n=10) and sex/age matched control participants (n=41 for psychometrics; n=59 for eye-tracking) were recruited from the PE-NET study or extracted from the NeuroDevNet study databases. Participants completed a selected array of psychometric tests which assessed executive function, working memory, attention, inhibition, visuospatial processing, reading, and math skills. Eye-tracking studies included the prosaccade, antisaccade, and memory-guided tasks. Psychometric testing revealed an impairment in working memory among PE-F1s. Eye-tracking studies revealed numerous impairments among PE-F1s including additional saccades required to reach the target, poor endpoint accuracy, and slower reaction time. However, PE-F1s made faster saccades than controls, and fewer sequence errors in the memory-guided task. Our study provides a comprehensive assessment of cognitive function among PE-F1s. The development of PE may be seen as an early predictor of reduced cognitive function in children, specifically in working memory and oculomotor control. Future studies should extended to a larger study populations, and may be valuable for early studies of children born to pregnancies complicated by other disorders, such as gestational diabetes or intrauterine growth restriction.

Executive Functioning in Children and Adolescents Prenatally Exposed to Alcohol: A Meta-Analytic Review

Prenatal alcohol exposure is associated with a constellation of adverse physical, neurocognitive and behavior outcomes, which comprise a continuum of disorders labeled Fetal Alcohol Spectrum Disorders (FASD). Extant research has consistently identified executive functions (EF) as a central impairment associated with FASD. Despite this, heterogeneity exists regarding the strength of the association between FASD and different EF, and this association has not yet been quantitatively synthesized. The current meta-analysis reviews 46 studies that compare children and adolescents with FASD to participants without FASD, on a variety of EF measures. In accordance with Miyake et al. Cognitive Psychology, 41, 49-100 (2000) three-factor model of EF, findings for the primary EF domains of working memory, inhibition, and set shifting are reviewed. Results indicate that children and adolescents with FASD demonstrate significant deficits across these EF, although the magnitude of effects diverged between EF, with working memory and inhibition yielding medium effects and set shifting yielding large effects. These results were moderated by sample characteristics, type of FASD diagnosis, and EF methodology. This quantitative synthesis offers novel future research directions.

Eye movements reveal sexually dimorphic deficits in children with fetal alcohol spectrum disorder

Background: We examined the accuracy and characteristics of saccadic eye movements in children with fetal alcohol spectrum disorder (FASD) compared with typically developing control children. Previous studies have found that children with FASD produce saccades that are quantifiably different from controls. Additionally, animal studies have found sex-based differences for behavioral effects after prenatal alcohol exposure. Therefore, we hypothesized that eye movement measures will show sexually dimorphic results.

Methods: Children (aged 5–18 years) with FASD (n = 71) and typically developing controls (n = 113) performed a visually-guided saccade task. Saccade metrics and behavior were analyzed for sex and group differences.

Results: Female control participants had greater amplitude saccades than control males or females with FASD. Accuracy was significantly poorer in the FASD group, especially in males, which introduced significantly greater variability in the data. Therefore, we conducted additional analyses including only those trials in which the first saccade successfully reached the target within a ± 1° window. In this restricted amplitude dataset, the females with FASD made saccades with significantly lower velocity and longer duration, whereas the males with FASD did not differ from the control group. Additionally, the mean and peak deceleration were selectively decreased in the females with FASD.

Conclusions: These data support the hypothesis that children with FASD exhibit specific deficits in eye movement control and sensory-motor integration associated with cerebellar and/or brain stem circuits. Moreover, prenatal alcohol exposure may have a sexually dimorphic impact on eye movement metrics, with males and females exhibiting differential patterns of deficit.

Response inhibition deficits in children with Fetal Alcohol Spectrum Disorder: relationship between diffusion tensor imaging of the corpus callosum and eye movement control

Response inhibition is the ability to suppress irrelevant impulses to enable goal-directed behavior. The underlying neural mechanisms of inhibition deficits are not clearly understood, but may be related to white matter connectivity, which can be assessed using diffusion tensor imaging (DTI). The goal of this study was to investigate the relationship between response inhibition during the performance of saccadic eye movement tasks and DTI measures of the corpus callosum in children with or without Fetal Alcohol Spectrum Disorder (FASD). Participants included 43 children with an FASD diagnosis (12.3 ± 3.1 years old) and 35 typically developing children (12.5 ± 3.0 years old) both aged 7-18, assessed at three sites across Canada. Response inhibition was measured by direction errors in an antisaccade task and timing errors in a delayed memory-guided saccade task. Manual deterministic tractography was used to delineate six regions of the corpus callosum and calculate fractional anisotropy (FA), mean diffusivity (MD), parallel diffusivity, and perpendicular diffusivity. Group differences in saccade measures were assessed using t-tests, followed by partial correlations between eye movement inhibition scores and corpus callosum FA and MD, controlling for age. Children with FASD made more saccade direction errors and more timing errors, which indicates a deficit in response inhibition. The only group difference in DTI metrics was significantly higher MD of the splenium in FASD compared to controls. Notably, direction errors in the antisaccade task were correlated negatively to FA and positively to MD of the splenium in the control, but not the FASD group, which suggests that alterations in connectivity between the two hemispheres of the brain may contribute to inhibition deficits in children with FASD.