Brain Imaging Studies of the Anatomical and Functional Consequences of Preterm Birth for Human Brain Development

Association between cortical thickness and cognitive ability in very preterm school-age children

Very preterm children, born before 32 weeks of gestation, are at risk for impaired cognitive function, mediated by several risk factors. Cognitive impairment can be measured by various neurodevelopmental assessments and is closely associated with structural alterations of brain morphometry, such as cortical thickness. However, the association between structural alterations and high-order cognitive function remains unclear. This study aimed to investigate the neurodevelopmental associations between brain structural changes and cognitive abilities in very preterm and full-term children. Cortical thickness was assessed in 37 very preterm and 24 full-term children aged 6 years. Cortical thickness analysis of structural T1-weighted images was performed using Advanced Normalization Tools. Associations between cortical thickness and the Wechsler Intelligence Scale for Children were evaluated by regression analysis based on ordinary least square estimation. Compared with full-term children, very preterm children showed significant differences in cortical thickness, variously associated with cognitive abilities in several brain regions. Perceptual reasoning indices were broadly correlated with cortical thickness in very preterm and full-term children. These findings provide important insights into neurodevelopment and its association with cortical thickness, which may serve as a biomarker in predictive models for neurodevelopmental diagnosis of high-order cognitive function.

Lower gestational age is associated with lower cortical volume and cognitive and educational performance in adolescence

BACKGROUND

Gestational age (GA) is associated with later cognition and behavior. However, it is unclear how specific cognitive domains and brain structural development varies with the stepwise change of gestational duration.

METHODS

This large-scale longitudinal cohort study analyzed 11,878 early adolescents' brain volume maps at 9-10 years (baseline) and 5685 at 11-12 years (a 2-year follow-up) from the Adolescent Brain Cognitive Development (ABCD) study. According to gestational age, adolescents were divided into five categorical groups: ≤ 33 weeks, 34-35 weeks, 36 weeks, 37-39 weeks, and ≥ 40 weeks. The NIH Toolbox was used to estimate neurocognitive performance, including crystallized and fluid intelligence, which was measured for 11,878 adolescents at baseline with crystallized intelligence and relevant subscales obtained at 2-year follow-up (with participant numbers ranging from 6185 to 6310 depending on the cognitive domain). An additional large population-based cohort of 618,070 middle adolescents at ninth-grade (15-16 years) from the Danish national register was utilized to validate the association between gestational age and academic achievements. A linear mixed model was used to examine the group differences between gestational age and neurocognitive performance, school achievements, and grey matter volume. A mediation analysis was performed to examine whether brain structural volumes mediated the association between GA and neurocognition, followed with a longitudinal analysis to track the changes.

RESULTS

Significant group differences were found in all neurocognitive scores, school achievements, and twenty-five cortical regional volumes (P < 0.05, Bonferroni corrected). Specifically, lower gestational ages were associated with graded lower cognition and school achievements and with smaller brain volumes of the fronto-parieto-temporal, fusiform, cingulate, insula, postcentral, hippocampal, thalamic, and pallidal regions. These lower brain volumes mediated the association between gestational age and cognitive function (P = 1 × 10^-8, β = 0.017, 95% CI: 0.007-0.028). Longitudinal analysis showed that compared to full term adolescents, preterm adolescents still had smaller brain volumes and crystallized intelligence scores at 11-12 years.

CONCLUSIONS

These results emphasize the relationships between gestational age at birth and adolescents' lower brain volume, and lower cognitive and educational performance, measured many years later when 9-10 and 11-12 years old. The study indicates the importance of early screening and close follow-up for neurocognitive and behavioral development for children and adolescents born with gestational ages that are even a little lower than full term.

Randomized Trial to Increase Speech Sound Differentiation in Infants Born Preterm

OBJECTIVE

To test whether infant-directed foreign language active learning would specifically increase speech sound differentiation to the intervention language while not decreasing differentiation in response to English.

STUDY DESIGN

Pilot randomized controlled trial of stable infants born preterm in the newborn intensive care unit with normal auditory brainstem responses, whose parents spoke only English and had no musical training or familial hearing abnormality. Assignment was to 1 of 3 groups: passive exposure to English infant-directed lullabies and readings (English-enrichment, control group) and contingent exposure by active sucking on a sensor-equipped pacifier to either infant-directed French lullabies and readings (English environment, French-contingent learning group) or infant-directed Mandarin lullabies and readings (English environment, Chinese-contingent learning group). The main outcome measures were preintervention and postintervention event-related potentials (ERPs) in response to standardized speech syllables in each language.

RESULTS

Forty-one subjects completed the study, including 15 in the English-enrichment control group and 13 each in the French-contingent and Chinese-contingent groups. The median gestational age at birth was 34 weeks (IQR, 8.75 weeks); postmenstrual age at intervention ranged from 36 to 46 weeks and was similar across the 3 groups. Postintervention mean ERP amplitude to pairs of English speech sounds did not differ across the 3 groups; however, ERP amplitude in French sound differentiation was greater in the French-contingent group than in the Chinese-contingent or English-enrichment groups, and ERP amplitude greater in Chinese sound differentiation was greater in the Chinese-contingent group compared with the other 2 groups.

CONCLUSION

Contingent infant-directed foreign language exposure increased speech sound differentiation specific to the intervention language and did not decrease differentiation in response to English.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03232931.

Relationships between early postnatal cranial ultrasonography linear measures and neurobehaviour at term-equivalent age in infants born <30 weeks' gestational age

BACKGROUND

The relationship between early postnatal brain development and neurobehaviour at term-equivalent age (TEA) remains uncertain.

AIM

We aimed to explore relationships between early postnatal cranial ultrasonography (cUS) linear measures of brain size and brain growth with neurobehaviour at TEA in infants born <30 weeks' gestational age (GA).

STUDY DESIGN

Prospective observational cohort study.

SUBJECTS

137 infants born <30 weeks' GA without major brain injury on neonatal cUS.

OUTCOME MEASURES

Neurobehaviour at TEA assessed using the General Movements Assessment (GMA) and Hammersmith Neonatal Neurological Examination (HNNE).

RESULTS

The GMA was administered in 115/137 (84%) infants; 80 (70%) presented with abnormal general movements (GMs) (79 poor repertoire, 1 cramped synchronised). The HNNE was assessed in 106/137 (77%) infants; 52 (49%) had a suboptimal total score. With respect to brain size, larger measures of the corpus callosum length (CCL) and right anterior horn width (AHW) at 1-month were related to lower risk of abnormal GMs, and larger measures of the biparietal diameter at 1-week and 2-months were related to lower risk of a suboptimal HNNE. As for brain growth, increases of the CCL and transcerebellar diameter between birth and 1-month, and left and right AHWs between 1- and 2-months, were related to lower risk of abnormal GMs.

CONCLUSION

Early postnatal brain size and brain growth were related to neurobehaviour at TEA in infants born <30 weeks' GA. This study provides preliminary evidence for the prognostic utility of early postnatal cUS linear measures as potential markers of neurodevelopment in later childhood.

Anti-Inflammatory Therapies for Treatment of Inflammation-Related Preterm Brain Injury

Despite the prevalence of preterm brain injury, there are no established neuroprotective strategies to prevent or alleviate mild-to-moderate inflammation-related brain injury. Perinatal infection and inflammation have been shown to trigger acute neuroinflammation, including proinflammatory cytokine release and gliosis, which are associated with acute and chronic disturbances in brain cell survival and maturation. These findings suggest the hypothesis that the inhibition of peripheral immune responses following infection or nonspecific inflammation may be a therapeutic strategy to reduce the associated brain injury and neurobehavioral deficits. This review provides an overview of the neonatal immunity, neuroinflammation, and mechanisms of inflammation-related brain injury in preterm infants and explores the safety and efficacy of anti-inflammatory agents as potentially neurotherapeutics.

Frühgeburtlichkeit und langfristige Folgen bis ins Schulalter

Zusammenfassung. Theoretischer Hintergrund: Frühgeborene (FG) haben ein erhöhtes langfristiges Entwicklungsrisiko. Dennoch gibt es in Deutschland kein konzertiertes Vorgehen zur Nachsorge bis ins Schulalter. Die heutigen Erkenntnisse zu Entwicklungsstörungen sind Grundlage einer qualifizierten Förderung. Fragestellung: Wie hoch sind Schulrückstellungsraten bei FG? Wie wird den schulischen Bedürfnissen FG Rechnung getragen? Methode: Evaluation der Schulrückstellung in einer aktuellen Kohorte sehr kleiner FG und qualitative Befragung von Lehrer_innen. Ergebnisse: Das Risiko für Schulrückstellungen ist bei FG erhöht. Lehrer_innen haben ein limitiertes Wissen zu Bedürfnissen FG und gleichzeitig hilfreiche Vorschläge für spezifische Förderung im Unterricht. Diskussion und Schlussfolgerung: Langfristige entwicklungsneurologische Nachsorge für FG ist dringend empfohlen, um potenzielle Probleme früh zu identifizieren, Interventionen zu initiieren und eine optimale Entfaltung des Entwicklungspotentials zu fördern.

Revisiting the roots of attachment: A review of the biological and psychological effects of maternal skin-to-skin contact and carrying of full-term infants

During the early period of hypothesis building and empirical testing of attachment theory, a major emphasis was placed on mother-infant physical contact. In spite of this, mother-infant contact has received scant attention amongst attachment and child development researchers in the past decades. Here, a brief theoretical framework for mother-infant contact is presented, drawing on animal studies as well as human studies of preterm infants and neonates. Salient mechanisms may include an extended sensitive period during early infancy, requiring specific somatosensory stimuli for bio-behavioral homeorhesis; oxytocinergic and epigenetic pathways; kinesthetic stimuli and face-to-face proximity allowing for increased social interaction. Studies of extended human mother-full-term infant physical contact have demonstrated positive effects in multiple domains. For infants, these include sleep organization, temperature and heart rate regulation, behavioral response, crying/colic, socio-emotional development, attachment quality, speech development opportunities and mother-child interactions. For mothers, studies demonstrate improved depressive symptomatology, physiological stress regulation, contingent responsivity, breastfeeding and mother-child interactions. Parent-infant attachment quality has gained prominence as a trauma-resilience factor as well as a predictor of adult physical health. The potential role of mother-infant contact as an attachment promoting intervention as well as future research subjects are discussed. Current evidence supports the original attachment research that early maternal touch provision may influence infant socio-emotional development and attachment quality, with positive implications for mother-child relationship functioning.

Recent Advances of Optical Imaging in the Second Near-Infrared Window

The near-infrared window between 1000 and 1700 nm, commonly termed the "second near-infrared (NIR-II) window," has quickly emerged as a highly attractive optical region for biological imaging. In contrast to conventional imaging in the visible region between 400 and 700 nm, as well as in the first NIR (NIR-I) window between 700 and 900 nm, NIR-II biological imaging offers numerous merits, including higher spatial resolution, deeper penetration depth, and lower optical absorption and scattering from biological substrates with minimal tissue autofluorescence. Noninvasive imaging techniques, specifically NIR-II fluorescence and photoacoustic (PA) imaging, have embodied the attractiveness of NIR-II optical imaging, with several NIR-II contrast agents demonstrating superior performance to the clinically approved NIR-I agents. Consequently, NIR-II biological imaging has been increasingly explored due to its tremendous potential for preclinical studies and clinical utility. Herein, the progress of optical imaging in the NIR-II window is reported. Starting with highlighting the importance of biological imaging in the NIR-II spectral region, the emergence and latest development of various NIR-II fluorescence and PA imaging probes and their applications are then discussed. Perspectives on the promises and challenges facing this nascent yet exciting field are then given.

Multidelay Arterial Spin-Labeling MRI in Neonates and Infants: Cerebral Perfusion Changes during Brain Maturation

BACKGROUND AND PURPOSE

Arterial spin-labeling with multiple postlabeling delays can correct transit times. We tried to evaluate CBF in neonates and infants using multidelay arterial spin-labeling.

MATERIALS AND METHODS

Multidelay arterial spin-labeling was applied to 13 preterm neonates (mean postmenstrual age, 34.9 weeks), 13 term-equivalent-age neonates (mean postmenstrual age, 39.2 weeks), and 6 infants (mean postmenstrual age, 57.8 weeks). Transit time-corrected CBF in the caudate, thalamus, frontal GM, occipital GM, frontal WM, and occipital WM was measured, and relative CBF compared with the whole-brain CBF was calculated. Inter- and intragroup comparisons were performed among the 3 age groups. A correlation and nonlinear regression analysis were performed between postmenstrual age and CBF.

RESULTS

Intergroup comparisons showed significantly higher whole-brain CBF in infants (38.3 mL/100 g/min) compared with preterm (15.5 mL/100 g/min) and term-equivalent-age (18.3 mL/100 g/min) neonates (P < .001). In the intragroup comparison, all 3 groups showed significantly higher relative CBF values in the occipital WM (63.6%-90.3%) compared with the frontal WM (46.3%-73.9%). In term-equivalent-age neonates, the occipital GM (120.8%) had significantly higher relative CBF values than the frontal GM (103.5%). There was a significant negative correlation between postmenstrual age and the relative CBF of the thalamus (r = - 0.449, P = .010). There were significant positive relationships between postmenstrual age and the relative CBF of the frontal WM (R ² = 0.298, P = .001) and occipital WM (R ² = 0.452, P < .001).

CONCLUSIONS

Multidelay arterial spin-labeling with transit time-corrected CBF showed developmental changes and regional differences of CBF in neonates and infants.

Dissociation in the Effects of Induced Neonatal Hypoxia-Ischemia on Rapid Auditory Processing and Spatial Working Memory in Male Rats

Infants born prematurely are at risk for cardiovascular events causing hypoxia-ischemia (HI; reduced blood and oxygen to the brain). HI in turn can cause neuropathology, though patterns of damage are sometimes diffuse and often highly variable (with clinical heterogeneity further magnified by rapid development). As a result, though HI injury is associated with long-term behavioral and cognitive impairments in general, pathology indices for specific infants can provide only limited insight into individual prognosis. The current paper addresses this important clinical issue using a rat model that simulates unilateral HI in a late preterm infant coupled with long-term behavioral evaluation in two processing domains - auditory discrimination and spatial learning/memory. We examined the following: (1) whether deficits on one task would predict deficits on the other (suggesting that subjects with more severe injury perform worse across all cognitive domains) or (2) whether domain-specific outcomes among HI-injured subjects would be uncorrelated (suggesting differential damage to orthogonal neural systems). All animals (sham and HI) received initial auditory testing and were assigned to additional auditory testing (group A) or spatial maze testing (group B). This allowed within-task (group A) and between-task (group B) correlation. Anatomic measures of cortical, hippocampal and ventricular volume (indexing HI damage) were also obtained and correlated against behavioral measures. Results showed that auditory discrimination in the juvenile period was not correlated with spatial working memory in adulthood (group B) in either sham or HI rats. Conversely, early auditory processing performance for group A HI animals significantly predicted auditory deficits in adulthood (p = 0.05; no correlation in shams). Anatomic data also revealed significant relationships between the volumes of different brain areas within both HI and shams, but anatomic measures did not correlate with any behavioral measure in the HI group (though we saw a hippocampal/spatial correlation in shams, in the expected direction). Overall, current data provide an impetus to enhance tools for characterizing individual HI-related pathology in neonates, which could provide more accurate individual prognoses within specific cognitive/behavioral domains and thus improved patient-specific early interventions.

Cortical structural abnormalities in very preterm children at 7 years of age

We analyzed long-lasting alterations in brain morphometry associated with preterm birth using volumetric and surface-based analyses applied to children at age 7 years. Comparison of 24 children born very preterm (VPT) to 24 healthy term-born children revealed reductions in total cortical gray matter volume, white matter volume, cortical surface area and gyrification index. Regional cortical shape abnormalities in VPT children included the following: shallower anterior superior temporal sulci, smaller relative surface area in the inferior sensori-motor cortex and posterior superior temporal cortex, larger relative surface area and a cingulate sulcus that was shorter or more interrupted in medial frontoparietal cortex. These findings indicate a complex pattern of regional vulnerabilities in brain development that may contribute to the diverse and long-lasting neurobehavioral consequences that can occur after very premature birth.

Regional impairments of cortical folding in premature infants

Objective

This study was undertaken to evaluate the influence of preterm birth and other factors on cerebral cortical maturation.

Methods

We have evaluated the effects of preterm birth on cortical folding by applying cortical cartography methods to a cohort of 52 preterm infants (<31 weeks gestation, mild or no injury on conventional magnetic resonance imaging) and 12 term-born control infants. All infants were evaluated at term-equivalent postmenstrual age.

Results

Preterm infants had lower values for the global measures of gyrification index (GI; 2.06 ± 0.07 vs 1.80 ± 0.12, p < 0.001; control vs preterm) and cortical surface area (CSA; 316 ± 24 cm² vs 257 ± 40 cm², p < 0.001). Regional analysis of sulcal depth and cortical shape showed the greatest impact of preterm birth on the insula, superior temporal sulcus, and ventral portions of the pre- and postcentral sulci in both hemispheres. Although CSA and GI are related, CSA was more sensitive to antenatal and postnatal factors than GI. Both measures were lower in preterm infants of lower birth weight standard deviation scores and smaller occipitofrontal circumference at time of scan, whereas CSA alone was lower in association with smaller occipitofrontal circumference at birth. CSA was also lower in infants with higher critical illness in the first 24 hours of life, exposure to postnatal steroids, and prolonged endotracheal intubation.

Interpretation

Preterm birth disrupts cortical development in a regionally specific fashion with abnormalities evident by term-equivalent postmenstrual age. This disruption is influenced by both antenatal growth and postnatal course.

Processing of intentional and automatic number magnitudes in children born prematurely: evidence from fMRI

This study examined the neural correlates of intentional and automatic number processing (indexed by number comparison and physical Stroop task, respectively) in 6- and 7-year-old children born prematurely. Behavioral results revealed significant numerical distance and size congruity effects. Imaging results disclosed (1) largely overlapping fronto-parietal activation for intentional and automatic number processing, (2) a frontal to parietal shift of activation upon considering the risk factors gestational age and birth weight, and (3) a task-specific link between math proficiency and functional magnetic resonance imaging (fMRI) signal within distinct regions of the parietal lobes—indicating commonalities but also specificities of intentional and automatic number processing.

Hemisphere differences in speech-sound event-related potentials in intensive care neonates: associations and predictive value for development in infancy

Neurodevelopmental delays in intensive care neonates are common but difficult to predict. In children, hemisphere differences in cortical processing of speech are predictive of cognitive performance. We hypothesized that hemisphere differences in auditory event-related potentials in intensive care neonates are predictive of neurodevelopment in infancy, even in those born preterm. Event-related potentials to speech sounds were prospectively recorded in 57 infants (gestational age 24-40 weeks) prior to discharge. The Developmental Assessment of Young Children was performed at 6 and 12 months. Hemisphere differences in mean amplitudes increased with postnatal age (P < .01) but not with gestational age. Greater hemisphere differences were associated with improved communication and cognitive scores at 6 and 12 months, but decreased in significance at 12 months after adjusting for socioeconomic and clinical factors. Auditory cortical responses can be used in intensive care neonates to help identify infants at higher risk for delays in infancy.

Morphological features of the neonatal brain support development of subsequent cognitive, language, and motor abilities

Knowledge of the role of brain maturation in the development of cognitive abilities derives primarily from studies of school-age children to adults. Little is known about the morphological features of the neonatal brain that support the subsequent development of abilities in early childhood, when maturation of the brain and these abilities are the most dynamic. The goal of our study was to determine whether brain morphology during the neonatal period supports early cognitive development through 2 years of age. We correlated morphological features of the cerebral surface assessed using deformation-based measures (surface distances) of high-resolution MRI scans for 33 healthy neonates, scanned between the first to sixth week of postmenstrual life, with subsequent measures of their motor, language, and cognitive abilities at ages 6, 12, 18, and 24 months. We found that morphological features of the cerebral surface of the frontal, mesial prefrontal, temporal, and occipital regions correlated with subsequent motor scores, posterior parietal regions correlated with subsequent language scores, and temporal and occipital regions correlated with subsequent cognitive scores. Measures of the anterior and middle portions of the cingulate gyrus correlated with scores across all three domains of ability. Most of the significant findings were inverse correlations located bilaterally in the brain. The inverse correlations may suggest either that a more protracted morphological maturation or smaller local volumes of neonatal brain tissue supports better performance on measures of subsequent motor, language, and cognitive abilities throughout the first 2 years of postnatal life. The correlations of morphological measures of the cingulate with measures of performance across all domains of ability suggest that the cingulate supports a broad range of skills in infancy and early childhood, similar to its functions in older children and adults.

Maternal-preterm skin-to-skin contact enhances child physiologic organization and cognitive control across the first 10 years of life

BACKGROUND

Maternal-newborn contact enhances organization of the infant's physiological systems, including stress reactivity, autonomic functioning, and sleep patterns, and supports maturation of the prefrontal cortex and its ensuing effects on cognitive and behavioral control. Premature birth disrupts brain development and is associated with maternal separation and disturbances of contact-sensitive systems. However, it is unknown whether the provision of maternal-preterm contact can improve long-term functioning of these systems.

METHODS

We used the Kangaroo Care (KC) intervention and provided maternal-newborn skin-to-skin contact to 73 premature infants for 14 consecutive days compared with 73 case-matched control subjects receiving standard incubator care. Children were then followed seven times across the first decade of life and multiple physiologic, cognitive, parental mental health, and mother-child relational measures were assessed.

RESULTS

KC increased autonomic functioning (respiratory sinus arrhythmia, RSA) and maternal attachment behavior in the postpartum period, reduced maternal anxiety, and enhanced child cognitive development and executive functions from 6 months to 10 years. By 10 years of age, children receiving KC showed attenuated stress response, improved RSA, organized sleep, and better cognitive control. RSA and maternal behavior were dynamically interrelated over time, leading to improved physiology, executive functions, and mother-child reciprocity at 10 years.

CONCLUSIONS

These findings are the first to demonstrate long-term effects of early touch-based intervention on children's physiologic organization and behavioral control and have salient implications for the care practices of premature infants. Results demonstrate the dynamic cascades of child physiological regulation and parental provisions in shaping developmental outcome and may inform the construction of more targeted early interventions.

Diffusion properties of major white matter tracts in young, typically developing children

Brain development occurs rapidly during the first few years of life involving region-specific changes in both gray matter and white matter. Due to the inherent difficulties in acquiring magnetic resonance imaging data in young children, little is known about the properties of white matter in typically developing toddlers. In the context of an ongoing study of young children with autism spectrum disorder, we collected diffusion-weighted imaging data during natural nocturnal sleep in a sample of young (mean age=35months) typically developing male and female (n=41 and 25, respectively) children. Axial diffusivity, radial diffusivity, mean diffusivity and fractional anisotropy were measured at 99 points along the length of 18 major brain tracts. Influences of hemisphere, age, sex, and handedness were examined. We find that diffusion properties vary significantly along the length of the majority of tracks. We also identify hemispheric and sex differences in diffusion properties in several tracts. Finally, we find the relationship between age and diffusion parameters changes along the tract length illustrating variability in age-related white-matter development at the tract level.

Brain structure, number magnitude processing, and math proficiency in 6- to 7-year-old children born prematurely: a voxel-based morphometry study

The aim of the present voxel-based morphometry study was to examine the link between brain structure and number skills in a group of 6-7-year-old children born prematurely, which are considered to be an at-risk population for mathematical learning disabilities. Therefore, gray and white matter density values were extracted from brain areas previously reported to be relevant for number processing in developing brain systems and, thereafter, correlated with response time results tapping semantic number knowledge [i.e. numerical distance effect (NDE) derived from a number comparison task] as well as with general math proficiency (as indexed by a standardized calculation test). Behavioral results disclosed a significant NDE, thus indicating well-established number magnitude representations for one-digit numerals in our study group. Significant positive correlations between gray matter and NDE emerged in parietal regions (including the right anterior inferior and the left superior parietal lobe) and in the right superior temporal gyrus. Moreover, white matter and NDE were negatively correlated in the right anterior inferior parietal lobe and the right inferior frontal gyrus. Overall, our results are novel insofar as they show that in 6-7-year-old children born prematurely, individual differences in gray and white matter structures are associated with numerical skills. Importantly, in our study group the observed link between brain structure and behavioral performance emerges only regarding an experimental task tapping semantic number knowledge, whereas general math proficiency does not seem to be related to individual differences in brain structure in our study group.

Alterations in frontostriatal pathways in children born very preterm

AIM

Children born very preterm (<32wks' gestation) are at risk of white matter injury, particularly in frontostriatal pathways that mediate executive functioning. However, it is unclear whether very preterm children without evidence of neonatal brain injury manifest long-term white matter microstructural differences once they reach school age and if this is related to cognitive impairments.

METHOD

Twenty school-aged children born very preterm (11 males, nine females; mean age 8y 6mo, standard error [SE] 1.68mo, range 7y 7mo-9y 6mo; gestational age range 24-30wks, mean gestational age 26.9wks, SE 0.4wk; birthweight 988 g, SE 46 g, range 570-1424 g) without evidence of neonatal brain injury, and 20 sex- and age-matched term-born children (mean age 8y 4.8mo, SE 1.92mo; range 7y 2mo-9y-10.8mo) underwent neurodevelopmental assessment and diffusion tensor imaging.

RESULTS

Fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity were calculated within all white matter pathways and within frontostriatal projections. Children born preterm had decreased fractional anisotropy in the territories of the left external capsule, superior longitudinal fasciculus, uncinate fasciculus, and inferior fronto-occipital fasciculus. Measures of intelligence were negatively correlated with frontostriatal fractional anisotropy only in males born preterm.

INTERPRETATION

Results indicate that very preterm-born children exhibit white matter disturbances that persist into middle childhood, with potential sex differences in the association between these white matter alterations and cognitive function.

Striatal cholinergic functional alterations in hypoxic neonatal rats: Role of glucose, oxygen, and epinephrine resuscitation

Molecular processes regulating cholinergic functions play an important role in the control of respiration under hypoxia. Cholinergic alterations and its further complications in respiration due to hypoxic insult in neonatal rats and the effect of glucose, oxygen, and epinephrine resuscitation was evaluated in the present study. Receptor binding and gene expression studies were done in the corpus striatum to analyse the changes in total muscarinic receptors, muscarinic M1, M2, M3 receptors, and the enzymes involved in acetylcholine metabolism, choline acetyltransferase and acetylcholinesterase. Neonatal hypoxia decreased total muscarinic receptors with reduced expression of muscarinic M1, M2, and M3 receptor genes. The reduction in acetylcholine metabolism is indicated by the downregulated choline acetyltransferase and upregulated acetyl cholinesterase expression. These cholinergic disturbances were reversed to near control in glucose-resuscitated hypoxic neonates. The adverse effects of immediate oxygenation and epinephrine administration are also reported. The present findings points to the cholinergic alterations due to neonatal hypoxic shock and suggests a proper resuscitation method to ameliorate these striatal changes.

Effects of gestational age at birth on cognitive performance: a function of cognitive workload demands

Objective

Cognitive deficits have been inconsistently described for late or moderately preterm children but are consistently found in very preterm children. This study investigates the association between cognitive workload demands of tasks and cognitive performance in relation to gestational age at birth.

Methods

Data were collected as part of a prospective geographically defined whole-population study of neonatal at-risk children in Southern Bavaria. At 8;5 years, n = 1326 children (gestation range: 23–41 weeks) were assessed with the K-ABC and a Mathematics Test.

Results

Cognitive scores of preterm children decreased as cognitive workload demands of tasks increased. The relationship between gestation and task workload was curvilinear and more pronounced the higher the cognitive workload: GA² (quadratic term) on low cognitive workload: R² = .02, p<0.001; moderate cognitive workload: R² = .09, p<0.001; and high cognitive workload tasks: R² = .14, p<0.001. Specifically, disproportionally lower scores were found for very (<32 weeks gestation) and moderately (32–33 weeks gestation) preterm children the higher the cognitive workload of the tasks. Early biological factors such as gestation and neonatal complications explained more of the variance in high (12.5%) compared with moderate (8.1%) and low cognitive workload tasks (1.7%).

Conclusions

The cognitive workload model may help to explain variations of findings on the relationship of gestational age with cognitive performance in the literature. The findings have implications for routine cognitive follow-up, educational intervention, and basic research into neuro-plasticity and brain reorganization after preterm birth.

Language and reading skills in school-aged children and adolescents born preterm are associated with white matter properties on diffusion tensor imaging

Children born preterm are at risk for deficits in language and reading. They are also at risk for injury to the white matter of the brain. The goal of this study was to determine whether performance in language and reading skills would be associated with white matter properties in children born preterm and full-term. Children born before 36 weeks gestation (n=23, mean±SD age 12.5±2.0 years, gestational age 28.7±2.5 weeks, birth weight 1184±431 g) and controls born after 37 weeks gestation (n=19, 13.1±2.1 years, 39.3±1.0 weeks, 3178±413 g) underwent a battery of language and reading tests. Diffusion tensor imaging (DTI) scans were processed using tract-based spatial statistics to generate a core white matter skeleton that was anatomically comparable across participants. Fractional anisotropy (FA) was the diffusion property used in analyses. In the full-term group, no regions of the whole FA-skeleton were associated with language and reading. In the preterm group, regions of the FA-skeleton were significantly associated with verbal IQ, linguistic processing speed, syntactic comprehension, and decoding. Combined, the regions formed a composite map of 22 clusters on 15 tracts in both hemispheres and in the ventral and dorsal streams. ROI analyses in the preterm group found that several of these regions also showed positive associations with receptive vocabulary, verbal memory, and reading comprehension. Some of the same regions showed weak negative correlations within the full-term group. Exploratory multiple regression in the preterm group found that specific white matter pathways were related to different aspects of language processing and reading, accounting for 27-44% of the variance. The findings suggest that higher performance in language and reading in a group of preterm but not full-term children is associated with higher fractional anisotropy of a bilateral and distributed white matter network.

Reduced corticomotor excitability and motor skills development in children born preterm

The mechanisms underlying the altered neurodevelopment commonly experienced by children born preterm, but without brain lesions, remain unknown. While individuals born the earliest are at most risk, late preterm children also experience significant motor, cognitive and behavioural dysfunction from school age, and reduced income and educational attainment in adulthood. We used transcranial magnetic stimulation and functional assessments to examine corticomotor development in 151 children without cerebral palsy, aged 10-13 years and born after gestations of 25-41 completed weeks. We hypothesized that motor cortex and corticospinal development are altered in preterm children, which underpins at least some of their motor dysfunction. We report for the first time that every week of reduced gestation is associated with a reduction in corticomotor excitability that remains evident in late childhood. This reduced excitability was associated with poorer motor skill development, particularly manual dexterity. However, child adiposity, sex and socio-economic factors regarding the child's home environment soon after birth were also powerful influences on development of motor skills. Preterm birth was also associated with reduced left hemisphere lateralization, but without increasing the likelihood of being left handed per se. These corticomotor findings have implications for normal motor development, but also raise questions regarding possible longer term consequences of preterm birth on motor function.

[Autism and prematurity: state of the art]

Research has shown a high rate of autism spectrum disorders among very low birth weight children over the past decade. This paper proposes a literature review on this topic. Two generations of research have followed one another. The first retrospective studies found a high rate of ASD among premature babies. The second generation of prospective studies underlined and relativized this risk. Prospective research using screening tools (M-CHAT) have found around 20 % ASD, whereas 2 studies assessing the actual diagnosis found 5 % and 8 % ASD, 10 to 12 times more than in the general population. A number of hypotheses have been put forward to explain these high rates of ASD: sensory impairment associated with prematurity, white matter abnormalities, and cerebellar impairment. The authors propose complex models that take into account neurological deficits and the effects of perinatal events on interactive dynamics between infants and their caregivers. These models aim to allow suitable prevention and care for premature children with autism, a heavy additional handicap.

Quantitative tract-based white matter development from birth to age 2years

Few large-scale studies have been done to characterize the normal human brain white matter growth in the first years of life. We investigated white matter maturation patterns in major fiber pathways in a large cohort of healthy young children from birth to age two using diffusion parameters fractional anisotropy (FA), radial diffusivity (RD) and axial diffusivity (RD). Ten fiber pathways, including commissural, association and projection tracts, were examined with tract-based analysis, providing more detailed and continuous spatial developmental patterns compared to conventional ROI based methods. All DTI data sets were transformed to a population specific atlas with a group-wise longitudinal large deformation diffeomorphic registration approach. Diffusion measurements were analyzed along the major fiber tracts obtained in the atlas space. All fiber bundles show increasing FA values and decreasing radial and axial diffusivities during development in the first 2years of life. The changing rates of the diffusion indices are faster in the first year than the second year for all tracts. RD and FA show larger percentage changes in the first and second years than AD. The gender effects on the diffusion measures are small. Along different spatial locations of fiber tracts, maturation does not always follow the same speed. Temporal and spatial diffusion changes near cortical regions are in general smaller than changes in central regions. Overall developmental patterns revealed in our study confirm the general rules of white matter maturation. This work shows a promising framework to study and analyze white matter maturation in a tract-based fashion. Compared to most previous studies that are ROI-based, our approach has the potential to discover localized development patterns associated with fiber tracts of interest.

Differences in neural activation between preterm and full term born adolescents on a sentence comprehension task: implications for educational accommodations

Adolescent survivors of preterm birth experience persistent functional problems that negatively impact academic outcomes, even when standardized measures of cognition and language suggest normal ability. In this fMRI study, we compared the neural activation supporting auditory sentence comprehension in two groups of adolescents (ages 9-16 years); sentences varied in length and syntactic difficulty. Preterms (n=18, mean gestational age 28.8 weeks) and full terms (n=14) had scores on verbal IQ, receptive vocabulary, and receptive language tests that were within or above normal limits and similar between groups. In early and late phases of the trial, we found interactions by group and length; in the late phase, we also found a group by syntactic difficulty interaction. Post hoc tests revealed that preterms demonstrated significant activation in the left and right middle frontal gyri as syntactic difficulty increased. ANCOVA showed that the interactions could not be attributed to differences in age, receptive language skill, or reaction time. Results are consistent with the hypothesis that preterm birth modulates brain-behavior relations in sentence comprehension as task demands increase. We suggest preterms' differences in neural processing may indicate a need for educational accommodations, even when formal test scores indicate normal academic achievement.

Motor system development of the preterm and low birthweight infant

Despite advances in knowledge and technology, accurate prediction of later neuromotor outcomes for infants born preterm remains somewhat elusive. Here we review some of the most recent findings regarding the differential effects of preterm birth and suboptimal fetal growth on neurodevelopment. Evidence from transcranial magnetic stimulation studies is presented that suggests neuromotor development may more directly influence cognitive outcomes than previously recognised. We discuss the role of neuroplasticity in both exacerbating and improving these postnatal outcomes, and possible therapeutic targets for manipulating this. Finally, some developmental care practices that might affect long-term outcomes for these children are discussed.

Adverse effects of heavy prenatal maternal smoking on attentional control in children with ADHD

OBJECTIVE

Exposure to heavy maternal cigarette smoking in pregnancy and severe maternal psychosocial stress during pregnancy appear to be important risk factors for the development of ADHD. This study aimed to determine whether these perinatal risk factors were associated with neuropsychological deficits commonly seen in ADHD.

METHOD

We examined the effect of these two risk factors on measures of attentional control, motor inhibition, visual-motor integration, and fine motor coordination in a group of 81 children with ADHD, aged from 8 to 18 years. The neuropsychological battery included the Connors' Continuous Performance Test (CPT), the Stroop Color-Word Interference Test, the Beery Visual-Motor Integration Test, and the Purdue Pegboard Test.

RESULTS

Heavy maternal smoking during pregnancy was associated with slower reaction times (p < .002), and reaction time variability (p < .007) on the CPT.

CONCLUSIONS

This study suggests a persistent negative effect of heavy prenatal maternal smoking on attentional control in children with ADHD. Future studies should examine the neurobiological basis and determine the degree to which inherited genetic susceptibility factors contribute to this finding.

Decreased GABAB receptor function in the cerebellum and brain stem of hypoxic neonatal rats: role of glucose, oxygen and epinephrine resuscitation

Background-

Hypoxia during the first week of life can induce neuronal death in vulnerable brain regions usually associated with an impairment of cognitive function that can be detected later in life. The neurobiological changes mediated through neurotransmitters and other signaling molecules associated with neonatal hypoxia are an important aspect in establishing a proper neonatal care.

Methods-

The present study evaluated total GABA, GABA_B receptor alterations, gene expression changes in GABA_B receptor and glutamate decarboxylase in the cerebellum and brain stem of hypoxic neonatal rats and the resuscitation groups with glucose, oxygen and epinephrine. Radiolabelled GABA and baclofen were used for receptor studies of GABA and GABA_B receptors respectively and Real Time PCR analysis using specific probes for GABA_B receptor and GAD mRNA was done for gene expression studies.

Results-

The adaptive response of the body to hypoxic stress resulted in a reduction in total GABA and GABA_B receptors along with decreased GABA_B receptor and GAD gene expression in the cerebellum and brain stem. Hypoxic rats supplemented with glucose alone and with oxygen showed a reversal of the receptor alterations and changes in GAD. Resuscitation with oxygen alone and epinephrine was less effective in reversing the receptor alterations.

Conclusions-

Being a source of immediate energy, glucose can reduce the ATP-depletion-induced changes in GABA and oxygenation, which helps in encountering hypoxia. The present study suggests that reduction in the GABA_B receptors functional regulation during hypoxia plays an important role in central nervous system damage. Resuscitation with glucose alone and glucose and oxygen to hypoxic neonatal rats helps in protecting the brain from severe hypoxic damage.

Early maternal anxiety predicts cognitive and behavioural outcomes of VLBW children at 24 months corrected age

AIM

The present study examined the effects of maternal anxiety during infant hospitalization in the Neonatal Intensive Care Unit (NICU) on the child's cognitive and behavioural development at 24 months corrected age. Parental anxiety following the birth of a very low birthweight (VLBW, <1500 g) infant may impede their capacity to be sensitive to the infant's cues and adversely affect infant developmental outcomes.

METHODS

A sample of 88 mothers and their VLBW infants were recruited in the NICU; 57 were followed at 24 months corrected age. During the infant's hospitalization, mothers completed a self-report measure of trait anxiety. When the infants were 24 months corrected age, mother-child interaction was videotaped during free play at home. These videotaped observations were coded using Emotional Availability Scales. Child cognitive and behavioural outcomes were evaluated using the Bayley Scales of Infant Development (II) and the Child Behavior Checklist for Ages 1.5-5.

RESULTS

Maternal anxiety in the NICU was found to be a significant and independent predictor of child cognitive development and internalizing behaviour problems, controlling for maternal education and neonatal morbidity.

CONCLUSION

These results suggest that early intervention programmes targeting anxious mothers of VLBW infants are indicated, to promote optimal developmental outcomes.

Processing speed mediates executive function difficulties in very preterm children in middle childhood

Executive function and attention difficulties are reported in very preterm (VPT) children at school entry, but it is unclear if these remain at later ages and/or if these difficulties are mediated by more basic functions, such as processing speed. Processing speed has been shown to underlie academic and behavioral problems in VPT children in middle childhood (Mulder, Pitchford, & Marlow, 2010, 2011), so may also underpin executive function and attention difficulties. We investigated this by comparing VPT (gestational age <31 weeks; N = 56) to term children (N = 22) aged 9-10 years on a comprehensive battery of executive function and attention tasks from the Test of Everyday Attention for Children (Manly, Robertson, Anderson, & Nimmo-Smith, 1999) and NEPSY (Korkman, Kirk, & Kemp, 1998). Selective and sustained attention, inhibition, working memory, shifting, verbal fluency, planning, and processing speed were examined. Group differences favoring term children were shown on most executive function tasks (i.e., inhibition, working memory, verbal fluency, and shifting), all of which were mediated by slow processing speed in the VPT group, except response inhibition. Seemingly, processing speed is an important determinant underpinning many neuropsychological deficits seen in VPT children in middle childhood.

Infant brain development and vulnerability to later internalizing difficulties: the Generation R study

OBJECTIVE

Although clinical studies have demonstrated smaller subcortical volumes in structures such as the amygdala, hippocampus, caudate nucleus, and thalamus in adults and adolescents with depressive disorders and anxiety, no study has assessed such structures in babies, long before the development of the disorders. This study examined whether the size of the "gangliothalamic ovoid" (encompassing the basal ganglia and thalamus) assessed during infancy is associated with increased internalizing problems in early childhood.

METHOD

Cranial ultrasounds were used to assess gangliothalamic ovoid diameter and ventricular volume at 6 weeks of postnatal age; moreover, head circumference was measured. Outcome data included ratings of internalizing and externalizing problems using the Child Behavior Checklist (reported by mothers and fathers) at 18 and/or 36 months. Analyses were based on a total of 651 children.

RESULTS

Smaller gangliothalamic diameter was associated with higher Child Behavior Checklist Internalizing scores at ages 18 and 36 months. Results remained significant after correcting for head circumference and were evident for the DSM-oriented subscales of anxiety problems and affective problems. Total ventricular volume was not consistently associated with Internalizing scores.

CONCLUSIONS

Findings associating infant brain measurements with Child Behavior Checklist mother and father reports at two time points are consistent with previous cross-sectional reports of smaller subcortical volumes in depression. Results were not simply reflective of overall brain development, because the pattern held after adjustment for head circumference. This is the first study to point toward a biological vulnerability evident in infancy, involved in the development of internalizing problems in childhood.

Alterations in cortical GABAB receptors in neonatal rats exposed to hypoxic stress: role of glucose, oxygen, and epinephrine resuscitation

Hypoxia in neonates can cause permanent brain damage by gene and receptor level alterations mediated through changes in neurotransmitters. The present study evaluated GABA(B) receptor alterations, gene expression changes in glutamate decarboxylase and hypoxia-inducible factor 1A in the cerebral cortex of hypoxic neonatal rats and the resuscitation groups with glucose, oxygen, and epinephrine. Under hypoxic stress, a significant decrease in total GABA and GABA(B) receptors, GABA(B) and GAD gene expression was observed in the cerebral cortex, which accounts for the respiratory inhibition. Hypoxia-inducible factor 1A was upregulated under hypoxia to maintain body homeostasis. Hypoxic rats supplemented with glucose alone and with oxygen showed a reversal of the receptor alterations and changes in GAD and HIF-1A to near control. Being a source of immediate energy, glucose can reduce the ATP-depletion-induced changes in GABA and oxygenation, which helps in encountering hypoxia. Resuscitation with oxygen alone and epinephrine was less effective in reversing the receptor alterations. Thus, our study suggests that reduction in the GABA(B) receptors functional regulation during hypoxia plays an important role in cortical damage. Resuscitation with glucose alone and glucose and oxygen to hypoxic neonatal rats helps in protecting the brain from severe hypoxic damage.

Risk factors affecting school readiness in premature infants with respiratory distress syndrome

OBJECTIVE

With advances in neonatal care, more children born prematurely are successfully reaching school age. It is unknown how many will be ready for school and what factors affect school readiness. Our objective was to assess readiness of children born prematurely for entry into public school, and determine risk factors associated with lack of school readiness in this population.

METHODS

This was a single-center prospective cohort study. Follow- up data were collected for 135 of 167 (81%) surviving premature infants with RDS requiring surfactant-replacement therapy. The children were seen between July 2005 and September 2006 (average age: 5.7 +/- 1.0 years) and underwent standardized neurodevelopmental and health assessments and socioeconomic status classification. A 4-level school-readiness score was constructed by using each child's standardized scores on assessments of basic concepts (Bracken School-Readiness Assessment), perceptual skills (Visual-Motor Integration Test), receptive vocabulary (Peabody Picture Vocabulary Test, Third Edition), daily living functional skills (Pediatric Functional Independence Measure), and presence of sensory impairments or autism. Proportional odds models were used to identify risk factors predicting lower school-readiness levels.

RESULTS

Mean birth weight was 1016 +/- 391 g, and mean gestational age was 27.5 +/- 2.6 weeks. Ninety-one (67%) children were school-ready. Using multivariate analysis, male gender, chronic lung disease, and severe intraventricular hemorrhage or periventricular leukomalacia were associated with lower school-readiness levels. However, the most powerful factor determining school-readiness level was low socioeconomic status.

CONCLUSION

Interventions targeting neonatal morbidities may be much less effective at improving overall performance at school age compared with the effect of the impoverished social environment.

Assessment and treatment of suicide risk in bipolar disorders

Completed suicide and suicide attempts are major issues in the management of bipolar disorders. There is evidence that suicide rates among these patients are more than 20-fold higher than the general population and, furthermore, suicidal behavior is much more lethal in bipolar disorder than in the general population. Patients with mood disorders may sometimes exhibit highly perturbed mixed states, which usually increase the risk of suicide. Such states are particularly frequent in bipolar II patients, especially if patients are treated with antidepressant monotherapy (unprotected by mood stabilizers), when depression switches into mania (or vice versa), or when depression lifts and functioning approaches normality. Researchers worldwide agree that treatment involving lithium is the best way to protect patients from suicide risk. Psychosocial activities, including psychoeducation, can protect bipolar patients either directly or, more probably, indirectly by increasing adherence to treatment and helping in daily difficulties that otherwise may lead to demoralization or hopelessness. An extensive understanding of the psychosocial circumstances and the psychopathology of bipolar patients (including temperament) may help clinicians describe the clinical picture accurately and prevent suicidal behavior in these patients.

Persistent maternal anxiety affects the interaction between mothers and their very low birthweight children at 24 months

BACKGROUND

Parental distress following the birth of a premature infant diminishes the parent's ability to be sensitive to the infant's cues, and this may affect infant developmental outcomes.

AIMS

The present study examined the effects of maternal anxiety during infant hospitalization in the Neonatal Intensive Care Unit (NICU) on the interactive behavior of mothers with their very low birthweight (VLBW) children in toddlerhood.

SUBJECTS

A sample of 56 mothers and their VLBW infants were recruited in the NICU.

STUDY DESIGN

During the infant's NICU stay, mothers completed a self-report measure of trait anxiety. These mothers and their infants were followed when the infants were 24 months corrected age, when mothers and their children were videotaped during free play at home. These videotapes were then coded using the Emotional Availability Scales.

RESULTS

Maternal anxiety was not found to be related to severity of neonatal illness. Maternal anxiety in the NICU was associated with less sensitivity and less structure in interaction with their toddlers at 24 months corrected age, even controlling for maternal education and child birthweight. Children of mothers with higher anxiety scores in the NICU were less likely to involve their mothers in their play at 24 months corrected age.

CONCLUSIONS

Maternal anxiety in the NICU predicted adverse interactive behaviors when the children were 24 months corrected age. Early identification of anxious mothers in the NICU is needed in order to initiate preventive intervention to support the mother-infant relationship.

EEG functional connectivity in term age extremely low birth weight infants

OBJECTIVE

The hypothesis is tested that electrocortical functional connectivity (quantified by coherence) of extremely low birth weight (ELBW) infants, measured at term post-menstrual age, has regional differences from that of full term infants.

METHODS

128 lead EEG data were collected during sleep from 8 ELBW infants with normal head ultrasound exams and 8 typically developing full term infants. Regional spectral power and coherence were calculated.

RESULTS

No significant regional differences in EEG power were found between infant groups. However, compared to term infants, ELBW infants had significantly reduced interhemispheric coherence (in frontal polar and parietal regions) and intrahemispheric coherence (between frontal polar and parieto-occipital regions) in the 1-12Hz band but increased interhemispheric coherence between occipital regions in the 24-50Hz band.

CONCLUSIONS

ELBW infants at term post-menstrual age manifest regional differences in EEG functional connectivity as compared to term infants.

SIGNIFICANCE

Distinctive spatial patterns of electrocortical synchrony are found in ELBW infants. These regional patterns may presage regional alterations in the structure of the cortex.

The offer they can't refuse: parents and perinatal treatment decisions

Despite a widespread myth of parental autonomy in decision-making for extremely preterm neonates, families in the United States are often not given access to accurate information about the consequences of preterm birth, resuscitation and treatment, or about their ethical options. Professional, philosophical, and financial incentives for hospitals and neonatologists to provide intensive treatment may trump parental wishes in delivery rooms and neonatal units. Parents may also be intimidated by the atmosphere of intensive care and by the behavior of committed staff. Prenatal advance directives allow parents to receive information on outcomes, treatments, and options, including palliative care, 'on their own turf' and as a part of routine prenatal counseling. The use of directives and other techniques for transparency in obstetric and neonatal care could improve the process of informed parental choice.

Preterm infant hippocampal volumes correlate with later working memory deficits

Children born preterm exhibit working memory deficits. These deficits may be associated with structural brain changes observed in the neonatal period. In this study, the relationship between neonatal regional brain volumes and working memory deficits at age 2 years were investigated, with a particular interest in the dorsolateral prefrontal cortex, parietal cortex and the hippocampus. While the eligible sample consisted of 227 very preterm children who were born at the Royal Women's Hospital, Melbourne prior to 30 weeks gestation or weighing <1250 g, 156 children had complete data sets. Neonatal magnetic resonance images of the brain were obtained at term equivalent age and subsequently parcellated into eight sub-regions, while the hippocampus was manually segmented. The relationship between brain volumes for these regions and performance on a working memory task (delayed alternation) at 2 years of age was examined. Very preterm children who perseverated on the working memory task had significantly smaller hippocampal volumes than very preterm children who exhibited intact working memory, even after adjusting for relevant perinatal, sociodemographic and developmental factors. Preterm children appear to have altered hippocampal volumes by discharge from hospital which may have a lasting impact on working memory function.

Periventricular white matter hyperintensities as predictors of suicide attempts in bipolar disorders and unipolar depression

The aim of this study was to evaluate whether deep white matter hyperintensities (DWMH) and periventricular white matter hyperintensities (PVH) are associated with suicidal behavior in patients with major affective disorders. Subjects were 99 consecutively admitted inpatients (42 men; 57 women; mean age: 46.5 years [SD=15.2; Min./Max.=19/79]) with a diagnosis of major affective disorder (bipolar disorder type I, bipolar disorder type-II and unipolar major depressive disorder). 44.4% of the participants had made at least one previous suicide attempt. T2-weighted brain magnetic resonance images were rated for the presence and extension of WMH using the modified Fazekas scale. Patients were interviewed for clinical data on average 5 days after admission. Bivariate analyses, corrected for multiple-testing, and logistic regression analysis were used to test the association between suicide attempts and clinical variables. Attempters and nonattempters differed only in the presence of PVH--the former were more likely to have PVH. The logistic regression indicated that the presence of PVH was robustly associated with suicidal behaviors after controlling for age (OR: 8.08). In conclusion, neuroimaging measures may be markers of risk for suicidal attempts in patients with major affective disorders.