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The supply of freshwater to estuarine ecosystems is a critical factor in maintaining the overall health and organization of coastal marshes. Specifically along the Texas Gulf coast, the coupled effects of decreased freshwater inflows to the estuary and natural processes (e.g., precipitation, wind, and tides) can exert significant salt-stress on coastal marsh vegetation. In this project we sought to quantitatively link the inflow of freshwater to the estuary (San Antonio Bay) with Aransas National Wildlife Refuge (ANWR) coastal marsh salinity and assess the influence of salinity and inundation on Carolina wolfberry (Lycium carolinianum Walt.) phenology (leaf and fruit abundance). The Carolina wolfberry is one of the more common high marsh plant species found at ANWR and has been shown to be a key food source for endangered Whooping Cranes which inhabit the coastal marshes of the ANWR each fall/winter. Results from our study show that periods of decreased freshwater inflows to the estuary correlated with increased marsh salinity at the ANWR. Wolfberry plants at ANWR marsh sites displayed increased fruit abundance during years which had lower mean summer time salinity (June, July, and August) in San Antonio Bay; conversely, during years of increased bay salinity during the same summertime months, wolfberry plants showed decreased fruit abundance. Through the continued validation of the relationship between inflows and coastal marsh salinity, we hope to provide additional insight into how wolfberry phenology varies inter-annually across both salinity and inundation regimes and how freshwater inflows may affect food availability for the endangered Whooping Crane.

The degree of hydrological connectivity in wetlands plays a vital role in determining the flux of energy, material, and nutrients across these wet landscapes. During the last century, compartmentalization of hydrologic flows in the Florida Everglades by canals and levees has had a profound impact on the natural timing and supply of freshwater and nutrients across the southern Everglades. Nitrogen (N) is an understudied nutrient in the phosphorus-limited Everglades; it plays an important role in many Everglades processes. To gain a better understanding of the overall N-dynamics in southern Everglades’ marshes and the role that canals play in the distribution of N across this landscape, we analyzed δ15N natural abundance data for the primary ecosystem components (the macrophyte Cladium jamaicense, marl soils, peat soils, and periphyton). Three sample transects were established in the three main basins of the southern Everglades: Shark River Slough, Taylor Slough, and the C-111 basin. Each transect included sample sites near canal inflows, in interior marshes, and at the estuarine ecotone. Natural abundance δ15N signatures provided insights into processes that may be enriching the 15N content of ecosystem components across the marsh landscape. We also conducted a combined analysis of δ15N data, tissue N concentrations, and water column N data to provide a broad overview of N cycling in the freshwater marshes of the southern Everglades. The primary trend that emerged from each basin was a significant 15N enrichment of all ecosystem components at near-canal sites, relative to more downstream sample sites. These data suggest that the phosphorus-limited marshes of the southern Everglades are not inactive conduits for N. Rather, these marshes appear to be actively cycling and processing N as it flows from the canal–marsh interface through downstream freshwater marshes. This finding has important implications to downstream coastal estuaries, including Florida Bay, and to nearshore coastal ocean ecosystems, such as coral reefs, where N is the limiting nutrient.

Background: MRI studies, including recent diffusion tensor imaging (DTI) studies, have shown corpus callosum abnormalities in children prenatally exposed to alcohol, especially in the posterior regions. These abnormalities appear across the range of fetal alcohol spectrum disorders (FASD). Several studies have demonstrated cognitive correlates of callosal abnormalities in FASD including deficits in visual-motor skill, verbal learning, and executive functioning. The goal of this study was to determine whether inter-hemispheric structural connectivity abnormalities in FASD are associated with disrupted inter-hemispheric functional connectivity and disrupted cognition. Methods: Twenty-one children with FASD and 23 matched controls underwent a 6-minute resting-state functional MRI scan as well as anatomical imaging and DTI. Using a semi-automated method, we parsed the corpus callosum and delineated 7 inter-hemispheric white matter tracts with DTI tractography. Cortical regions of interest (ROIs) at the distal ends of these tracts were identified. Right–left correlations in resting fMRI signal were computed for these sets of ROIs, and group comparisons were made. Correlations with facial dysmorphology, cognition, and DTI measures were computed. Results: A significant group difference in inter-hemispheric functional connectivity was seen in a posterior set of ROIs, the para-central region. Children with FASD had functional connectivity that was 12% lower than in controls in this region. Subgroup analyses were not possible owing to small sample size, but the data suggest that there were effects across the FASD spectrum. No significant association with facial dysmorphology was found. Para-central functional connectivity was significantly correlated with DTI mean diffusivity, a measure of microstructural integrity, in posterior callosal tracts in controls but not in FASD. Significant correlations were seen between these structural and functional measures, and Wechsler perceptual reasoning ability. Conclusions: Inter-hemispheric functional connectivity disturbances were observed in children with FASD relative to controls. The disruption was measured in medial parietal regions (para-central) that are connected by posterior callosal fiber projections. We have previously shown microstructural abnormalities in these same posterior callosal regions, and the current study suggests a possible relationship between the two. These measures have clinical relevance as they are associated with cognitive functioning.

Diffusion tensor imaging was used to evaluate cerebral white matter in eight patients (ages 10-17), with myotonic dystrophy type 1 (3 congenital-onset, 5 juvenile-onset) compared to eight controls matched for age and sex. Four regions of interest were examined: inferior frontal, superior frontal, supracallosal, and occipital. The myotonic dystrophy group showed white matter abnormalities compared to controls in all regions. All indices of white matter integrity were abnormal: fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. With no evidence of regional variation, correlations between whole cerebrum white matter fractional anisotropy and neurocognitive functioning were examined in the patients. Strong correlations were observed between whole cerebrum fractional anisotropy and full-scale intelligence and a measure of executive functioning. Results indicate that significant white matter abnormality is characteristic of young patients with myotonic dystrophy type 1 and that the white matter abnormality seen with neuroimaging has implications for cognitive functioning.

Schizophrenia is a heterogeneous neurodevelopmental disorder. Patients with high levels of negative symptoms have been identified as a specific subtype, but little is known about how the neurodevelopmental course may differ in this group. This study aimed to characterize developmental trajectories of premorbid social withdrawal and cognitive decline between patients with high versus low levels of negative symptoms in youth with schizophrenia-spectrum disorders.A standardized timeline was used to delineate the emergence of psychosis, social withdrawal, and cognitive decline in 52 subjects aged 8 to 19 with schizophrenia (n=36), schizophreniform (n=6), or schizoaffective disorder (n=10). The sample was divided into subgroups of high- (n=26) versus low- (n=26) negative symptoms, and developmental trajectories of premorbid symptoms were compared between groups.Mean ages for emergence of social withdrawal, cognitive decline, and psychosis were 11.1 years (SD=2.5), 11.9 (SD=4.4) and 13.2 years (SD=1.2), respectively. In the high-negative symptom group, the premorbid developmental trajectory for social withdrawal was more protracted. This group also had more severe cognitive decline at the onset of psychosis, but the premorbid trajectories for cognitive decline did not differ significantly between groups.This work documents a more severe and protracted trajectory of premorbid social withdrawal in patients with high levels of negative symptoms in comparison to those with low-negative symptoms. The findings reported here are supportive of the hypothesis that patients with illness characterized by high levels of negative symptoms may represent a subgroup with distinct neurodevelopmental abnormalities.

Ragan, A.N. and Wozniak, J.R., 2019. Linking hydrologic connectivity in salt marsh ponds to fish assemblages across a heterogenous coastal habitat. Journal of Coastal Research, 35(3), 545–...

Diffusion tensor imaging was used to investigate white matter (WM) integrity in adults with traumatic brain injury (TBI) and healthy adults as controls. Adults with TBI had sustained severe vehicular injuries on the average of 7 years earlier. A multivariate analysis of covariance with verbal IQ as the covariate revealed that adults with TBI had lower fractional anisotropy and higher mean diffusivity than controls, specifically in the three regions of interest (ROIs), the centrum semiovale (CS), the superior frontal (SPF), and the inferior frontal (INF). Adults with TBI averaged in the normal range in motor speed and two of three executive functions and were below average in delayed verbal recall and inhibition, whereas controls were above average. Time since injury, but not age, was associated with WM changes in the SPF ROI, whereas age, but not time since injury, was associated with WM changes in the INF ROI, suggesting that the effects of WM on time since injury may interact with age. To understand the utility of WM changes in chronic recovery, larger sample sizes are needed to investigate associations between cognition and WM integrity of severely injured individuals who have substantial cognitive impairment compared to severely injured individuals with little cognitive impairment. (JINS, 2009, 15, 130–136.)

The physical, cognitive, and behavioral correlates of Fetal Alcohol Spectrum Disorders (FASD) have been well-researched. However, there is minimal investigation of the non-biological correlates of cognition and behavior in this population. The association between foster care placement history and cognitive and behavioral functioning was explored using archival data from 136 children with FASD. Significant cognitive and behavioral abnormalities were found in the overall sample. Children with one foster care placement performed significantly better on measures of verbal intelligence, mathematics achievement, and impulse control and endorsed fewer symptoms of internalizing disorders compared to children who were never removed from their biological home. Children with multiple foster home placements generally fell between the other two groups on assessment measures. It may be important to consider placement history of children with FASD when attempting to understand their cognitive and behavioral abn...

Kleptomania is characterized by the failure to resist impulses to steal objects not needed for personal use or their monetary value. The objective of this study was to examine cognitive and executive functioning in subjects with kleptomania. Fifteen women with a primary DSM-IV diagnosis of kleptomania underwent a detailed psychiatric examination, including measures of kleptomania severity, and a battery of neuropsychological tests that emphasized executive functions. Correlational analyses were computed between measures of kleptomania severity and tests of executive functioning. Kleptomania subjects reported a mean duration of illness of 17.9 years and shoplifting a mean of 1.7 times per week. All subjects reported an inability to resist urges to shoplift. Neuropsychological testing revealed group mean test scores within 0.5 standard deviations of normative standards for age. Five subjects (33.3%), however, had below-average performance on at least one measure of executive functioning, and 4 (26.7%) had below-average scores on two executive measures. Correlational analyses revealed a statistically significant correlation between kleptomania severity and Wisconsin Card Sorting Test performance ( r = - 0.693 , p = 0.004 ). As a group, subjects with kleptomania did not demonstrate deficits on neuropsychological testing. Greater kleptomania symptom severity, however, was correlated with impairment in executive functioning.

This study examined the sensitivity of diffusion tensor imaging (DTI) to microstructural white matter (WM) damage in mild and moderate pediatric traumatic brain injury (TBI). Fourteen children with TBI and 14 controls ages 10-18 had DTI scans and neurocognitive evaluations at 6-12 months post-injury. Groups did not differ in intelligence, but children with TBI showed slower processing speed, working memory and executive deficits, and greater behavioral dysregulation. The TBI group had lower fractional anisotropy (FA) in three WM regions: inferior frontal, superior frontal, and supracallosal. There were no group differences in corpus callosum. FA in the frontal and supracallosal regions was correlated with executive functioning. Supracallosal FA was also correlated with motor speed. Behavior ratings showed correlations with supracallosal FA. Parent-reported executive deficits were inversely correlated with FA. Results suggest that DTI measures are sensitive to long-term WM changes and associated with cognitive functioning following pediatric TBI.

© 2015 Elsevier Inc.. Objectives: Precise characterization of cognitive outcomes and factors that contribute to cognitive variability will enable better understanding of disease progression and treatment effects in mucopolysaccharidosis type I (MPS I). We examined the effects on cognition of phenotype, genotype, age at evaluation and first treatment, and somatic disease burden. Methods: Sixty patients with severe MPS IH (Hurler syndrome treated with hematopoietic cell transplant and 29 with attenuated MPS I treated with enzyme replacement therapy), were studied with IQ measures, medical history, genotypes. Sixty-seven patients had volumetric MRI. Subjects were grouped by age and phenotype and MRI and compared to 96 normal controls. Results: Prior to hematopoietic cell transplant, MPS IH patients were all cognitively average, but post-transplant, 59% were below average, but stable. Genotype and age at HCT were associated with cognitive ability. In attenuated MPS I, 40% were below average with genotype and somatic disease burden predicting their cognitive ability. White matter volumes were associated with IQ for controls, but not for MPS I. Gray matter volumes were positively associated with IQ in controls and attenuated MPS I patients, but negatively associated in MPS IH. Conclusions: Cognitive impairment, a major difficulty for many MPS I patients, is associated with genotype, age at treatment and somatic disease burden. IQ association with white matter differed from controls. Many attenuated MPS patients have significant physical and/or cognitive problems and receive insufficient support services. Results provide direction for future clinical trials and better disease management.

The 2014 Fetal Alcohol Spectrum Disorders Study Group (FASDSG) meeting focused on the dual themes of the risks associated with low to moderate alcohol exposure during pregnancy and knowledge translation practices to enhance the impact of scientific research. The meeting theme was titled “Low drinking versus no drinking: Matching science with policy and public perception.” Despite decades of basic science and clinical evidence that has documented the risks associated with prenatal alcohol exposure, there still exists confusion and uncertainty on the part of health professionals and the public regarding the question of whether or not there is a “safe” level of alcohol consumption during pregnancy. The first keynote presentation reviewed the data obtained from large-scale epidemiological studies that have attempted to address the question of relative risk associated with low to moderate alcohol exposure during pregnancy. This presentation was followed by an expert panel discussion of the state of scientific evidence obtained from clinical and basic science investigations concerning this question, and strategies for moving research evidence into policy and practice. The second keynote presentation presented a framework for knowledge translation and mobilization to move research discoveries toward implementation. The conference also featured updates by government agencies, FASt data talks that highlighted new and innovative findings in FASD research, and award presentations, including a lifetime achievement award presented to Dr. Kenneth Warren to acknowledge his longstanding support for FASD research. A highlight of the meeting was the presentation of the 2014 Henry Rosett award to Dr. Philip May in recognition of his substantial contributions to epidemiological studies on FASD.

The phenotype of attenuated mucopolysaccharidosis type II (MPS II), also called Hunter syndrome, has not been previously studied in systematic manner. In contrast to the “severe” phenotype, the “attenuated” phenotype does not present with behavioral or cognitive impairment; however, the presence of mild behavior and cognitive impairment that might impact long-term functional outcomes is unknown. Previously, significant MRI abnormalities have been found in MPS II. Recent evidence suggests white matter abnormalities in many MPS disorders. Methods As the initial cross-sectional analysis of a longitudinal study, we studied the association of brain volumes and somatic disease burden with neuropsychological outcomes, including measures of intelligence, memory, and attention in 20 patients with attenuated MPS II with a mean age of 15.8. MRI volumes were compared to 55 normal controls. Results While IQ and memory were average, measures of attention were one standard deviation below the average range. Corpus callosum volumes were significantly different from age-matched controls, differing by 22%. Normal age-related volume increases in white matter were not seen in MPS II patients as they were in controls. Somatic disease burden and white matter and corpus callosum volumes were significantly associated with attention deficits. Neither age at evaluation nor age at starting treatment predicted attention outcomes. Conclusions Despite average intelligence, attention is compromised in attenuated MPS II. Results confirm an important role of corpus callosum and cortical white matter abnormality in MPS II as well as the somatic disease burden in contributing to attention difficulties. Awareness by the patient and caregivers with appropriate management and symptomatic support will benefit the attenuated MPS II patient.

Background: Fetal alcohol spectrum disorders (FASDs) are conditions characterized by physical anomalies, neurodevelopmental abnormalities, and neurocognitive deficits, including intellectual, executive, and memory deficits. There are no specific biological treatments for FASDs, but rodent models have shown that prenatal or postnatal choline supplementation reduces cognitive and behavioral deficits. Potential mechanisms include phospholipid production for axonal growth and myelination, acetylcholine enhancement, and epigenetic effects. Objective: Our primary goal was to determine whether postnatal choline supplementation has the potential to improve neurocognitive functioning, particularly hippocampal-dependent memory, in children with FASDs. Design: The study was a double-blind, randomized, placebo-controlled pilot trial in children (aged 2.5–5 y at enrollment) with FASDs (n = 60) who received 500 mg choline or a placebo daily for 9 mo. Outcome measures were Mullen Scales of Early Learning (primary) and the elicited imitation (EI) memory paradigm (secondary). Results: The administration proved feasible, and choline was well tolerated. Participants received a dose on 88% of enrolled days. The only adverse event linked to choline was a fishy body odor. Choline supplementation improved the secondary outcome (EI) only after immediate recall performance was controlled for, and the outcome was moderated by age. The treatment effect on EI items recalled was significant in the younger participants (2.5- to ≤4.0-y-olds); the young choline group showed an increase of 12–14 percentage points greater than that of the young placebo group on delayed recall measures during treatment. However, there was a marginal baseline difference in delayed item recall between the young choline and placebo groups as well as a potential ceiling effect for item recall, both of which likely contributed to the observed treatment effect. We also observed a trend toward a negative effect of choline supplementation on the immediate EI recall of ordered pairs; the young placebo group showed an increase of 8–17 percentage points greater than that of the choline group during treatment. There was an inverse relation between choline dose (in mg/kg) and memory improvement (P = 0.041); the data suggest that weight-adjusted doses may be a better alternative to a fixed dose in future studies. Limitations included trend-level baseline differences in performance, the post-hoc determination of age moderation, and potential ceiling effects for the memory measure. Conclusions: This pilot study suggests that an additional evaluation of choline supplementation as an intervention for memory functioning in children with FASDs is warranted. The observed interaction between age and choline’s effect on EI suggests that potential sensitive periods should be considered in future work. This trial was registered at clinicaltrials.gov as {"type":"clinical-trial","attrs":{"text":"NCT01149538","term_id":"NCT01149538"}}NCT01149538.

Because prenatal alcohol exposure is associated with growth deficiency, little attention has been paid to the potential for overweight and obesity in children with fetal alcohol spectrum disorders (FASD). This study examined the prevalence of overweight/obesity (body mass index [BMI]) in a large clinical sample of children with FASD.Children, aged 2 to 19 years, who were evaluated for FASD at University Clinics, included 445 with an FASD diagnosis and 171 with No-FASD diagnosis. Prevalence of overweight/obesity (BMI ≥ 85 percentile) was compared to national and state prevalence. BMI was examined in relation to FASD diagnosis, gender, and age. Dietary intake data were examined for a young subsample (n = 42).Thirty-four percent with any FASD diagnosis were overweight or obese, which did not differ from the No-FASD group or U.S. prevalence. Underweight was prevalent in those with fetal alcohol syndrome (FAS) (17%). However, increased rates of overweight/obesity were seen in those with partial FAS (40%). Among adolescents, those with any FASD diagnosis had increased overweight/obesity (42%), particularly among females (50%). The rate in adolescent females with FASD (50%) was nearly 3 times higher than state prevalence for adolescent females (17 to 18%), p0.001. In the young subsample, those who were overweight/obese consumed more calories, protein, and total fat per day than those who were not overweight or obese.Rates of overweight/obesity are increased in children with partial FAS. In adolescents, rates are increased for any FASD diagnosis (particularly in females). Results are suggestive of possible metabolic/endocrine disruption in FASD-a hypothesis for which there is evidence from animal models. These data suggest that clinicians may consider prenatal alcohol exposure as a risk factor for metabolic/endocrine disruption, should evaluate diet as a risk in this population, and may need to target interventions to females prior to puberty to effect changes in overweight-related outcomes.

Brain functional connectivity has been studied by analyzing time series correlations in regional brain activities based on resting-state fMRI data. Brain functional connectivity can be depicted as a network or graph defined as a set of nodes linked by edges. Nodes represent brain regions and an edge measures the strength of functional correlation between two regions. Most of existing work focuses on estimation of such a network. A key but inadequately addressed question is how to test for possible differences of the networks between two subject groups, say between healthy controls and patients. Here we illustrate and compare the performance of several state-of-the-art statistical tests drawn from the neuroimaging, genetics, ecology and high-dimensional data literatures. Both real and simulated data were used to evaluate the methods. We found that, Network Based Statistic (NBS) performed well in many but not all situations, and its performance critically depends on the choice of its threshold parameter, which is unknown and difficult to choose in practice. Importantly, two adaptive statistical tests called adaptive sum of powered score (aSPU) and its weighted version (aSPUw) are easy to use and complementary to NBS, being higher powered than NBS in some situations. The aSPU and aSPUw tests can be also applied to adjust for co-variates. Between the aSPU and aSPUw tests, they often, but not always, performed similarly with neither one as a uniform winner. On the other hand, Multivariate Matrix Distance Regression (MDMR) has been applied to detect group differences for brain connectivity; with the usual choice of the Euclidean distance, MDMR is a special case of the aSPU test. Consequently NBS, aSPU and aSPUw tests are recommended to test for group differences in functional connectivity.

Executive function (EF) deficit is a hallmark of Fetal Alcohol Spectrum Disorders (FASD), but the vast majority of available evidence comes from school-age children and adolescents. Very little is known about EF during the critical developmental period prior to 6 years of age in FASD. We evaluated EF in 39 children with FASD (3.0-5.5 years) and a comparison group of 50 age-matched, nonexposed controls. Measures included the EF Scale for Early Childhood and a Delay of Gratification task. Compared to age-matched controls, preschool children with FASD had impairments on the EF Scale and showed more impulsivity on the Delay of Gratification task. To confirm the EF Scale finding, FASD group performance was compared to a separate normative dataset (N = 1,400). Those with FASD performed below normal (M = -0.57, SD = 0.92). Within the FASD group, IQ was correlated with the EF Scale (partial r = .60, p = .001) and Delay of Gratification (partial r = .58, p = .005). EF Scale performance did not differ significantly across levels of FASD severity (fetal alcohol syndrome [FAS], partial FAS, or alcohol-related neurobehavioral disorder [ARND]). However, compared to normative data, those with FAS had the largest deficits (M = -0.91 SD from the mean, SE = 0.23), followed by partial FAS (M = -0.66 SD from the mean, SE = 0.26), then ARND (M = -0.36 SD from the mean, SE = 0.20). These novel data show that EF deficits manifest well before the age of 6 years in children with FASD, that they occur across the spectrum, and that EF may be most impaired in children with more severe forms of FASD and/or lower IQs.

Cocaine dependence is a particularly severe problem in the United States, resulting in broad economic and personal costs. Significant evidence of generalized cognitive deficits associated with cocaine dependence has been reported. Two studies evaluated whether context processing, the processes involved in representing and maintaining information regarding the context of one's environment, might be seen as a process-specific deficit that may explain some aspects of the broader cognitive deficits associated with cocaine dependence. Study 1 used the expectancy variant of the AX task to assess this ability; Study 2 employed the Dot Pattern Expectancy task. Significant between-groups differences were found in each study for d'-context, a comparison of AX hits and BX misses; these results indicated significant between-groups differences in context-processing ability. In Study 1, significant between-groups a priori contrasts of AY versus BX trials indicated the likelihood of a specific deficit in context processing in the cocaine group; however, this contrast was not significant in Study 2. Overall, the results of these studies support the theory of impaired context-processing ability associated with cocaine misuse. However, these results do not allow for the interpretation of a process-specific deficit in context-processing ability. Future research targeted at investigating aspects of this context-processing impairment associated with cocaine misuse can shed light on the specificity of this deficit.

This study evaluated dietary intake in children with fetal alcohol spectrum disorders (FASD). Pre-clinical research suggests that nutrient supplementation may attenuate cognitive and behavioral deficits in FASD. Currently, the dietary adequacy of essential nutrients in children with FASD is unknown. Dietary data were collected as part of a randomized, doubleblind controlled trial of choline supplementation in FASD. Participants included 31 children with FASD, ages 2.5 – 4.9 years at enrollment. Dietary intake data was collected three times during the nine month study via interview-administered 24-hour recalls with the Automated Self-Administered 24-hour Recall. Dietary intake of macronutrients and 17 vitamins/minerals from food were averaged across three data collection points. Observed nutrient intakes were compared to national dietary intake data of children ages 2 – 5 years (What we Eat in America, NHANES 2007–2008) and to the Dietary Reference Intakes. Compared to the dietary intakes of children in the NHANES sample, children with FASD had lower intakes of saturated fat, vitamin D, and calcium. The majority (>50%) of children with FASD did not meet the Recommended Dietary Allowance (RDA) or Adequate Intake (AI) for fiber, n-3 fatty acids, vitamin D, vitamin E, vitamin K, choline, and calcium. This pattern of dietary intake in children with FASD suggests that there may be opportunities to benefit from nutritional intervention. Supplementation with several nutrients including choline, vitamin D, and n-3 fatty acids, has been shown in animal models to attenuate the cognitive deficits of FASD. These results highlight the potential of nutritional clinical trials in FASD.

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.

To compare the eating behaviors and nutrition-related concerns in children with fetal alcohol spectrum disorder (FASD) with those in typically developing children.A survey that assessed eating behaviors was completed between October 2013 and May 2014 by the caregivers of children screened for FASD at the University of Minnesota's Fetal Alcohol Spectrum Disorders Program, and typically developing children recruited from that clinic or from the Research Participation Core of the Waisman Center, University of Wisconsin.Compared with controls (N = 81), children with FASD (N = 74) had delayed acquisition of self-feeding behavior (P.001) and solid food introduction (P.001). Impaired satiety was common and independent of medication use: 23.0% were never full/satisfied, 31.1% snacked constantly, and 27.0% concealed food (all P ≤ .002). They consumed the equivalent of an additional meal/snack daily (P.01). Children with FASD were more likely to have a past diagnosis of underweight (P.001). Mean body mass index was significantly reduced for males (P = .009) but not females (P = .775) with FASD, and only 2 children with FASD were currently underweight. Children with FASD were more physically active (P.01).Abnormal eating patterns are common in children with FASD and may contribute to their delayed growth and nutritional inadequacies. Their poor satiety may reflect poor impulse control. Children with FASD may benefit from diet counseling. Conversely, some children with hyperphagia may warrant referral for FASD screening.

Aim: Adolescents with psychotic disorders show deficits in IQ, attention, learning and memory, executive functioning, and processing speed that are related to important clinical variables including negative symptoms, adaptive functioning and academics. Previous studies have reported relatively consistent deficits with varying relationships to illness status and symptoms. The goals of this study were to examine these relationships in a larger sample at baseline, and also to examine the longitudinal course of these deficits in a smaller subset of adolescents. Method: Thirty-six subjects, aged 10 to 17 years, were included at baseline. All had Diagnostic and Statistical Manual-Fourth Edition diagnoses of schizophrenia, schizoaffective disorder, schizophreniform disorder and psychosis – not otherwise specified, as determined by Kiddie-Schedule for Affective Disorders and Schizophrenia for School-Age Children structured interviews. Patients were administered a neuropsychological battery, and Positive and Negative Syndrome Scale ratings were completed at baseline and again at 1 year (n = 14). Most participants were inpatients at baseline, and 13 of 14 were on atypical antipsychotic medication during both sessions. Results: At baseline, the patients demonstrated impairments in working memory, processing speed, executive function and verbal learning. No significant cognitive change was detected at 1-year follow-up. In contrast, clinical symptoms were variable across 1 year, with an improvement in positive symptoms at 1 year. No relationships between clinical and cognitive symptoms were observed, with the exception of baseline IQ predicting negative symptoms at 1 year. Conclusions: Young patients with schizophrenia-spectrum disorders displayed neurocognitive impairments at baseline. Despite measurable fluctuations in clinical symptoms over the year, no significant changes were measured in cognition. Lower IQ at baseline was predictive of more negative symptoms at 1 year.

Pathophysiological mechanisms underlying the clinically devastating CNS features of myotonic dystrophy (DM) remain more enigmatic and controversial than do the muscle abnormalities of this common form of muscular dystrophy. To better define CNS and cranial muscle changes in DM, we used quantitative volumetric and diffusion tensor MRI methods to measure cerebral and masticatory muscle differences between controls ( n =5) and adults with either congenital ( n =5) or adult onset ( n =5) myotonic dystrophy type 1 and myotonic dystrophy type 2 ( n =5). Muscle volumes were diminished in DM1 and strongly correlated with reduced white matter integrity and gray matter volume. Moreover, correlation of reduced fractional anisotropy (white matter integrity) and gray matter volume in both DM1 and DM2 suggests that these abnormalities may share a common underlying pathophysiological mechanism. Further quantitative temporal and spatial characterization of these features will help delineate developmental and progressive neurological components of DM, and help determine the causative molecular and cellular mechanisms.

MRI studies, including recent diffusion tensor imaging (DTI) studies, have shown corpus callosum abnormalities in children prenatally exposed to alcohol, especially in the posterior regions. These abnormalities appear across the range of fetal alcohol spectrum disorders (FASD). Several studies have demonstrated cognitive correlates of callosal abnormalities in FASD including deficits in visual-motor skill, verbal learning, and executive functioning. The goal of this study was to determine whether inter-hemispheric structural connectivity abnormalities in FASD are associated with disrupted inter-hemispheric functional connectivity and disrupted cognition.Twenty-one children with FASD and 23 matched controls underwent a 6-minute resting-state functional MRI scan as well as anatomical imaging and DTI. Using a semi-automated method, we parsed the corpus callosum and delineated 7 inter-hemispheric white matter tracts with DTI tractography. Cortical regions of interest (ROIs) at the distal ends of these tracts were identified. Right-left correlations in resting fMRI signal were computed for these sets of ROIs, and group comparisons were made. Correlations with facial dysmorphology, cognition, and DTI measures were computed.A significant group difference in inter-hemispheric functional connectivity was seen in a posterior set of ROIs, the para-central region. Children with FASD had functional connectivity that was 12% lower than in controls in this region. Subgroup analyses were not possible owing to small sample size, but the data suggest that there were effects across the FASD spectrum. No significant association with facial dysmorphology was found. Para-central functional connectivity was significantly correlated with DTI mean diffusivity, a measure of microstructural integrity, in posterior callosal tracts in controls but not in FASD. Significant correlations were seen between these structural and functional measures, and Wechsler perceptual reasoning ability.Inter-hemispheric functional connectivity disturbances were observed in children with FASD relative to controls. The disruption was measured in medial parietal regions (para-central) that are connected by posterior callosal fiber projections. We have previously shown microstructural abnormalities in these same posterior callosal regions, and the current study suggests a possible relationship between the two. These measures have clinical relevance as they are associated with cognitive functioning.

Over the past 5 years, Diffusion Tensor Imaging (DTI) has begun to provide new evidence about the effects of prenatal alcohol exposure on white matter development. DTI, which examines microstructural tissue integrity, is sensitive to more subtle white matter abnormalities than traditional volumetric MRI methods. Thus far, the available DTI data suggest that white matter microstructural abnormalities fall on a continuum of severity in Fetal Alcohol Spectrum Disorder (FASD). Abnormalities are prominent in the corpus callosum, but also evident in major anterior-posterior fiber bundles, corticospinal tracts, and cerebellum. These subtle abnormalities are correlated with neurocognitive deficits, especially in processing speed, non-verbal ability, and executive functioning. Future studies using larger samples, increasingly sophisticated DTI methods, and additional functional MRI connectivity measures will better characterize the full range of abnormalities in FASD. Ultimately, these measures may serve as indices of change in future longitudinal studies and in studies of interventions for FASD.

Background: Several studies have now shown corpus callosum abnormalities using diffusion tensor imaging (DTI) in children with fetal alcohol spectrum disorders (FASD) in comparison with nonexposed controls. The data suggest that posterior regions of the callosum may be disproportionately affected. The current study builds on previous efforts, including our own work, and moves beyond midline corpus callosum to probe major inter-hemispheric white matter pathways with an improved DTI tractographic method. This study also expands on our prior work by evaluating a larger sample and by incorporating children with a broader range of clinical effects including full-criteria fetal alcohol syndrome (FAS). Methods: Participants included 33 children with FASD (8 FAS, 23 partial FAS, 2 static encephalopathy) and 19 nonexposed controls between the ages of 10 and 17 years. Participants underwent DTI scans and intelligence testing. Groups (FASD vs. controls) were compared on fractional anisotropy (FA) and mean diffusivity (MD) in 6 white matter tracts projected through the corpus callosum. Exploratory analyses were also conducted examining the relationships between DTI measures in the corpus callosum and measures of intellectual functioning and facial dysmorphology. Results: In comparison with the control group, the FASD group had significantly lower FA in 3 posterior tracts of the corpus callosum: the posterior mid-body, the isthmus, and the splenium. A trend-level finding also suggested lower FA in the genu. Measures of white matter integrity and cognition were correlated and suggest some regional specificity, in that only posterior regions of the corpus callosum were associated with visual-perceptual skills. Correlations between measures of facial dysmorphology and posterior regions of the corpus callosum were nonsignificant. Conclusions: Consistent with previous DTI studies, these results suggest that microstructural posterior corpus callosum abnormalities are present in children with prenatal alcohol exposure and cognitive impairment. These abnormalities are clinically relevant because they are associated with cognitive deficits and appear to provide evidence of abnormalities associated with prenatal alcohol exposure independent of dysmorphic features. As such, they may yield important diagnostic and prognostic information not provided by the traditional facial characteristics.

The concentration and flux of nitrogen (N) and phosphorus (P) through mangrove wetlands, seagrass meadows, and coral reef habitats are mediated by a wide range of hydrodynamic and chemical pathways determined by both natural and anthropogenic drivers. The direct proximity of these coastal habitats to burgeoning urban centers makes them quite susceptible to excessive nutrient loading, subsequent land-use impacts, the related effects of eutrophication and of course the associated loss of ecosystem services. For this reason mangrove, seagrass, and coral reef ecosystems are among the most threatened ecosystems in the tropics. While quantifying the exchange of materials between coastal wetlands and nearshore waters has been the focus of estuarine research for nearly half a century, a concerted effort to understand the net exchange of N and P across these habitats has only begun in the last 20 years. Furthermore, attempts to better understand the interplay of N and P cycles specifically between each of these three habitats has been all but nonexistent. The role mangrove and seagrass ecosystems play in buffering nearshore coral habitats from land-based influences remains a topic of great debate. Critical to understanding the nutrient dynamics between these ecosystems is defining the frequency and magnitude of connectivity events that link these systems together both physically and biogeochemically. In this chapter we attempt to address both N and P water column concentrations and system-level exchanges (i.e., water-mediated fluxes and nutrient loading). We consider how the interactions of N and P between these systems vary with geomorphology, hydrography, seasonal programming, and human influences.

Rationale Two previous studies have utilized diffusion tensor imaging (DTI) to examine microstructural integrity in cocaine abuse and found evidence of brain abnormalities in white matter. Objective Using anatomical magnetic resonance imaging (MRI), DTI, and clinical evaluation, the macrostructural and microstructural correlates of cocaine abuse were investigated. Methods Twenty-one men and women (mean age 42.5 and mean 18.9 years of cocaine use) and 21 age/gender-matched controls were included. Fractional anisotropy (FA) was measured in frontal white matter ROIs. Gray and white matter volumes in superior and inferior frontal regions were compared. Results DTI data revealed that cocaine users had lower FA than controls, specifically in inferior frontal white matter. FA differences were not seen in other areas. Significant volumetric differences were not seen, but both gray and white matter inferior frontal volumes trended toward smaller in the cocaine group. The data suggested that duration of use was associated with decreased gray and white matter volumes. FA and gray matter volume were correlated in cocaine users. Conclusions Both macrostructural and microstructural abnormalities were seen in a group of cocaine abusers. Length of cocaine use was associated with severity of the brain abnormalities. Future studies of white matter tissue integrity are warranted including examination of the relationship between DTI measures and traditional volumetric measures.