Posterior structural brain volumes differ in maltreated youth with and without chronic posttraumatic stress disorder.

Magnetic resonance imaging studies of maltreated children with posttraumatic stress disorder (PTSD) suggest that maltreatment-related PTSD is associated with adverse brain development. Maltreated youth resilient to chronic PTSD were not previously investigated and may elucidate neuromechanisms of the stress diathesis that leads to resilience to chronic PTSD. In this cross-sectional study, anatomical volumetric and corpus callosum diffusion tensor imaging measures were examined using magnetic resonance imaging in maltreated youth with chronic PTSD (N = 38), without PTSD (N = 35), and nonmaltreated participants (n = 59). Groups were sociodemographically similar. Participants underwent assessments for strict inclusion/exclusion criteria and psychopathology. Maltreated youth with PTSD were psychobiologically different from maltreated youth without PTSD and nonmaltreated controls. Maltreated youth with PTSD had smaller posterior cerebral and cerebellar gray matter volumes than did maltreated youth without PTSD and nonmaltreated participants. Cerebral and cerebellar gray matter volumes inversely correlated with PTSD symptoms. Posterior corpus callosum microstructure in pediatric maltreatment-related PTSD differed compared to maltreated youth without PTSD and controls. The group differences remained significant when controlling for psychopathology, numbers of Axis I disorders, and trauma load. Alterations of these posterior brain structures may result from a shared trauma-related mechanism or an inherent vulnerability that mediates the pathway from chronic PTSD to comorbidity.

Influence of analysis technique on measurement of diffusion tensor imaging parameters.

OBJECTIVE: We compared results from various methods of analysis of diffusion tensor imaging (DTI) data from a single dataset consisting of 10 healthy adolescents. SUBJECTS AND METHODS: All subjects were imaged on a single 3-T MRI system (single-shot echo-planar imaging pulse sequence; b value, 1000 s/mm(2)). We measured fractional anisotropy (FA), apparent diffusion coefficient (ADC), and axial and radial diffusivity values using 64-pixel rectangular regions of interest (ROIs) in the right side, midline, and left side of the central portion of the splenium of the corpus callosum for fixed (i.e., at same sites in all subjects) and targeted (i.e., at sites of highest FA values) locations. We compared results with those obtained using 64-pixel oval ROIs and 100-pixel rectangular ROIs in the same locations. Finally, we compared results from ROI-based methods and from tractography. All comparisons used the Wilcoxon signed rank test and the intraclass correlation of individual values. RESULTS: Compared to tractography, the average of mean ROI-based values was significantly higher for fixed (approximately 14%) and targeted (approximately 39%) FA values and was significantly lower for ADC (approximately 16%) and radial diffusivity (approximately 38%) values. For solely ROI-based comparisons, statistically significant differences were found in the following comparisons: 64- versus 100-pixel ROI, oval versus rectangular ROI, targeted FA left of midline versus mean targeted FA value, and targeted ROI right of midline versus mean targeted FA value. CONCLUSION: Markedly different values were obtained when using either ROI- or tractography-based techniques or ROI analysis techniques that differ only relatively slightly.

Demographic, maltreatment, and neurobiological correlates of PTSD symptoms in children and adolescents.

OBJECTIVE: To examine the relationships of demographic, maltreatment, neurostructural and neuropsychological measures with total posttraumatic stress disorder (PTSD) symptoms. METHODS: Participants included 216 children with maltreatment histories (N = 49), maltreatment and PTSD (N = 49), or no maltreatment (N = 118). Participants received diagnostic interviews, brain imaging, and neuropsychological evaluations. RESULTS: We examined a hierarchical regression model comprised of independent variables including demographics, trauma and maltreatment-related variables, and hippocampal volumes and neuropsychological measures to model PTSD symptoms. Important independent contributors to this model were SES, and General Maltreatment and Sexual Abuse Factors. Although hippocampal volumes were not significant, Visual Memory was a significant contributor to this model. CONCLUSIONS: Similar to adult PTSD, pediatric PTSD symptoms are associated with lower Visual Memory performance. It is an important correlate of PTSD beyond established predictors of PTSD symptoms. These results support models of developmental traumatology and suggest that treatments which enhance visual memory may decrease symptoms of PTSD.

Neuropsychological findings in childhood neglect and their relationships to pediatric PTSD.

Although child neglect is the most prevalent form of child maltreatment, the neurocognitive effects of neglect are understudied. We examined IQ, reading, mathematics, and neurocognitive domains of fine-motor skills, language, visual-spatial, memory/learning, and attention/executive functions in two groups of nonsexually abused medically healthy neglected children, one with DSM-IV posttraumatic stress disorder (PTSD) and one without, and a demographically similar healthy nonmaltreated control group. Significantly lower IQ, reading, mathematics, and selected differences in complex visual attention, visual memory, language, verbal memory and learning, planning, problem solving, and speeded naming were seen in Neglect Groups. The Neglect with PTSD Group performed worse than controls on NEPSY Design Copying, NEPSY Tower, and Mathematics; and performed worse than controls and Neglect without PTSD on NEPSY Memory for Faces-Delayed. Negative correlations were seen between PTSD symptoms, PTSD severity, and maltreatment variables, and IQ, Academic Achievement, and neurocognitive domains. Neglected children demonstrated significantly lower neurocognitive outcomes and academic achievement than controls. Lower IQ, neurocognitive functions, and achievement may be associated with more PTSD symptoms (particularly re-experiencing symptoms), greater PTSD severity, and a greater number of maltreatment experiences. Trauma experiences may additionally contribute to subsequent neurodevelopmental risk in neglected children. (JINS, 2009, 15, 868-878.).

A Pilot Study of Neurocognitive Function and Brain Structures in Adolescents With Alcohol Use Disorders: Does Maltreatment History Matter?

Neurocognitive and brain structural differences are associated with adolescent onset alcohol use disorders (AUDs). Maltreatment histories may contribute to current results. To examine these issues, healthy adolescents (n = 31), adolescents without maltreatment and AUD (AUD - MAL, n = 28), and adolescents with AUDs with maltreatment (AUD + MAL, n = 17) underwent comprehensive neurocognitive assessments and MRI structural scans. Controls performed significantly better than the two AUD groups in math and language. The AUD + MAL group performed significantly lower in sustained attention compared to the AUD - MAL and control groups and lower in reading compared to controls. The AUD + MAL group had larger left pars triangularis, a region of the inferior frontal gyrus, compared to the AUD-MAL and control groups, and smaller anterior corpus callosum volumes versus the AUD - MAL group. There were no group differences in other prefrontal cortex, amygdala, hippocampus, and parahippocampal volumes. The AUD + MAL group showed an inverse correlation between hippocampal volumes and age. AUD variables were associated with lower performance in fine-motor and executive function. Cannabis use variables were associated with lower performance in fine-motor, language, visual-spatial, memory, and executive function. Parahippocampal volumes positively correlated with abstinence. The preliminary results suggest adolescent AUD studies should consider examinations of maltreatment history, comorbid substance use disorders, and recovery during abstinence in their analyses.

Dimensions of Attention Associated With the Microstructure of Corona Radiata White Matter.

Mirsky proposed a model of attention that included these dimensions: focus/execute, sustain, stabilize, encode, and shift. The neural correlates of these dimensions were investigated within corona radiata subregions in healthy youth. Diffusion tensor imaging and neuropsychological assessments were conducted in 79 healthy, right-handed youth aged 4-17 years. Diffusion tensor imaging maps were analyzed using standardized parcellation methods. Partial Pearson correlations between neuropsychological standardized scores, representing these attention dimensions, and diffusion tensor imaging measures of corona radiata subregions were calculated after adjusting for gender and IQ. Significant correlations were found between the focus/execute, sustain, stabilize, and shift dimensions and imaging metrics in hypothesized corona radiata subregions. Results suggest that greater microstructural white matter integrity of the corona radiata is partly associated with attention across 4 attention dimensions. Findings suggest that white matter microstructure of the corona radiata is a neural correlate of several, but not all, attention dimensions.

The superior longitudinal fasciculus in typically developing children and adolescents: diffusion tensor imaging and neuropsychological correlates.

The relationship between superior longitudinal fasciculus microstructural integrity and neuropsychological functions were examined in 49 healthy children (range: 5-17 years) using diffusion tensor imaging. Seven major cognitive domains (intelligence, fine-motor, attention, language, visual-spatial, memory, executive function) were assessed. Data analyses used correlational methods. After adjusting for age and gender, fractional anisotropy and axial diffusivity values in the superior longitudinal fasciculus were positively correlated with executive functions of set shifting, whereas left superior longitudinal fasciculus fractional anisotropy values correlated with attention and language. Apparent diffusion coefficient values in the left superior longitudinal fasciculus negatively correlated with inhibitory control. In the left arcuate fasciculus, fractional anisotropy correlated with IQ and attention, whereas radial diffusivity values negatively correlated with IQ, fine-motor skills, and expressive language. Findings from this study provide an examination of the relationship between superior longitudinal fasciculus integrity and children's neuropsychological abilities that can be useful in monitoring pediatric neurologic diseases.

Neuropsychological findings in pediatric maltreatment: relationship of PTSD, dissociative symptoms, and abuse/neglect indices to neurocognitive outcomes.

Maltreated (n = 38), maltreated + posttraumatic stress disorder (PTSD; n = 60), and control youth (n = 104) underwent comprehensive neuropsychological testing. The two maltreated groups performed significantly lower on IQ, academic achievement, and nearly all of the neurocognitive domains than controls. Maltreated + PTSD performed significantly worse than maltreated youth without PTSD on a task in the visuospatial domain that assessed higher order visuoconstructive abilities. No group differences were evident on the fine motor domain. PTSD diagnosis duration negatively correlated with the visuospatial, and dissociation negatively correlated with the attention domain. Cumulative lifetime maltreatment types experienced negatively correlated with academic achievement. Sexual abuse negatively correlated with language and memory functions after controlling for other maltreatment types. These data support the adverse effects of maltreatment on neuropsychological functions in youth and suggest that all child protective services identified youth should be comprehensively examined for the integrity of their neuropsychological functioning and academic skills, regardless of the presence or absence of mental health symptoms.

Direct and Indirect Effects of Brain Volume, Socioeconomic Status and Family Stress on Child IQ.

11 BACKGROUND: A large literature documents the detrimental effects of socioeconomic disparities on intelligence and neuropsychological development. Researchers typically measure environmental factors such as socioeconomic status (SES), using income, parent's occupation and education. However, SES is more complex, and this complexity may influence neuropsychological outcomes. 12 METHODS: This studyused principal components analysis to reduce 14 SES and 28 family stress indicators into their core dimensions (e.g. community and educational capital, financial resources, marital conflict). Core dimensions were used in path analyses to examine their relationships with parent IQ and cerebral volume (white matter, grey matter and total brain volume), to predict child IQ in a sample of typically developing children. 13 RESULTS: Parent IQ affected child IQ directly and indirectly through community and educational capital, demonstrating how environmental factors interact with familial factors in neuro-development. There were no intervening effects of cerebral white matter, grey matter, or total brain volume. 14 CONCLUSIONS: Findings may suggest that improving community resources can foster the intellectual development of children.