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Abstract: The docosahexaenoic acid (DHA, C22:6n-3) status of infants at birth and maternal DHA intake during pregnancy are interconnected and associated with infants’ developmental performance. High-dosage supplementation of long-chain polyunsaturated fatty acids (LCPUFAs; particularly DHA) in mothers, started at mid-pregnancy, has been associated with long-term positive effects on intelligence quotient scores of neurodevelopment. Poor maternal and infant DHA status could partly contribute to the observed association between certain conditions and impaired developmental outcome. The dietary DHA enrichment of human milk seems to be functionally effective in breastfed infants only when lactating mothers start supplementation during pregnancy. Results from trials in artificially fed infants are dissimilar and could be related in part to uninvestigated covariates such as infant DHA status at birth and the individual genetic background. Nevertheless, DHA supplementation during the complementary feeding period seems to be effective in improving neurofunctional and visual performance. [ABSTRACT FROM AUTHOR]

Abstract: Motion cues provide a rich source of information about translations of the observer through the environment as well as the movements of objects and surfaces. While the direction of motion can be extracted locally these local measurements are, in general, insufficient for determining object and surface motions. To study the development of local and global motion processing mechanisms, we recorded Visual Evoked Potentials (VEPs) in response to dynamic random dot displays that alternated between coherent rotational motion and random motion at 0.8Hz. We compared the spatio-temporal tuning of the evoked response in 4–6months old infants to that of adults by recording over a range of dot displacements and temporal update rates. Responses recorded at the frequency of the coherent motion modulation were tuned for displacement at the occipital midline in both adults in infants. Responses at lateral electrodes were tuned for speed in adults, but not in infants. Infant responses were maximal at a larger range of spatial displacement than that of adults. In contrast, responses recorded at the dot-update rate showed a more similar parametric displacement tuning and scalp topography in infants and adults. Taken together, our results suggest that while local motion processing is relatively mature at 4–6months, global integration mechanisms exhibit significant immaturities at this age. [Copyright &y& Elsevier]

Background: Studies of infant siblings of children diagnosed with autism have allowed for a prospective approach to study the emergence of autism in infancy and revealed early behavioral characteristics of the broader autism phenotype. In view of previous findings of atypical eye gaze processing in children and adults with autism, the aim of this study was to examine the early autism phenotype in infant siblings of children diagnosed with autism spectrum disorder (sib-ASD), focusing on the neural correlates of direct compared with averted gaze. Methods: A group of 19 sib-ASD was compared with 17 control infants with no family history of ASD (mean age = 10 months) on their response to direct versus averted gaze in static stimuli. Results: Relative to the control group, the sib-ASD group showed prolonged latency of the occipital P400 event-related potentials component in response to direct gaze, but they did not differ in earlier components. Similarly, time-frequency analysis of high-frequency oscillatory activity in the gamma band showed group differences in response to direct gaze, where induced gamma activity was late and less persistent over the right temporal region in the sib-ASD group. Conclusion: This study suggests that a broader autism phenotype, which includes an atypical response to direct gaze, is manifest early in infancy. [Copyright &y& Elsevier]

Abstract: The present study investigated the role that comprehending words for objects plays in 10- and 11-month-old infants'' ability to individuate those objects in a spatiotemporally ambiguous event. To do this, we employed an object individuation task in which infants were familiarized to two objects coming in and out from behind a screen in alternation, and then the screen was removed to reveal either both or only one of the objects. Results show that only when 10- and 11-month-olds comprehend words for both objects seen do they exhibit looking behavior that is consistent with object individuation (i.e., looking longer when one of the objects is surreptitiously removed). Neither level of object permanence reasoning nor overall receptive vocabulary had an effect on performance in the object individuation task, indicating that the effect was specific to the immediate parameters of the situation, and not a function of overall precocity on the part of the succeeding infants. These results suggest that comprehending the words for occluded/disoccluded objects provides a kind of “glue” which allows infants to bind the mental index of an object with its perceptual features (thus precipitating the formation of two mental indexes, rather than one). They further suggest that a shift from object indexing driven by the where (dorsal) system to one which is driven by integration of the ventral and dorsal neural systems, usually not observed until 12 months of age, can be facilitated by word comprehension in 10- and 11-month-old infants. [Copyright &y& Elsevier]

The importance of the tear film for the integrity of the ocular surface is well established. Full-term neonates produce tears normally, but low spontaneous blink rates during early life raises important questions regarding tear dynamics and stability. Although an afferent neural pathway that could potentially detect tear break-up is in place at birth, there is indirect evidence that the neonatal tear film is adapted to resist evaporation-mediated tear thinning. This adaptation presumably prevents drying of the ocular surface during long inter-blink periods. However, low rates of tear turnover may have important implications for the defence of the eye against potential pathogens. [Copyright &y& Elsevier]

The Superposition Hypothesis states that the binocular vision of newborn infants blends together the monocular visual responses of the two eyes, even when the visual stimulus evokes binocular rivalry in adults. According to the Superposition Hypothesis, this blending is replaced by binocular rivalry after the emergence of stereopsis [Neonate Cognition: Beyond the Blooming, Buzzing Confusion, Erlbaum, Hillsdale, NJ, 1985, p. 37; Early Visual Development Normal and Abnormal, Oxford University Press, New York, 1993, p. 201]. The main evidence for the Superposition Hypothesis is a preferential looking experiment [Vision Res., 26 (3) (1986) 501], in which 8–12-week-old infants fixated a rivalrous (for adults) dichoptic plaid, in preference over a fusible grating of parallel lines. This report describes our attempt to repeat that important experiment. Infant stereopsis emerged at 8.6 weeks under our conditions, but infants did not preferentially fixate the dichoptic plaid at any age between age 5 and 16 weeks. Control experiments showed that our result was not due to technical differences between their experiment and ours (red/green vs. polarizing glasses, the use of a fixation point, or the infant observation apparatus). Therefore, blending of the visual responses to rivalrous (for adults) stimuli is not a general feature of the pre-stereoptic infant visual system. [Copyright &y& Elsevier]

Abstract: The presence of abnormal visual function has been related to overt lesions in the thalami, peritrigonal white matter (such as cavitational-necrotic periventricular leucomalacia) and optic radiations, and also to the extent of occipital cortex involvement. The normal development of visual function seems to depend on the integrity of a network that includes not only optic radiations and the primary visual cortex but also other cortical and subcortical areas, such as the frontal or temporal lobes or basal ganglia, which have been found to play a topical role in the development of vision. Therefore, the complex functions and functional connectivity of the developing brain of premature infants can be studied only with highly sophisticated techniques such as diffusion tensor tractography. The combined use of visual tests and neonatal structural and functional neuroimaging, which have become available for newborn infants, provides a better understanding of the correlation between structure and function from early life. This appears to be particularly relevant considering the essential role of early visual function in cognitive development. The identification of early visual impairment is also important, as it allows for early enrolment in intervention programmes. The association of clinical and functional studies to newer imaging techniques, which are being increasingly used also in neonates, are likely to provide further information on early aspects of vision and the mechanisms underlying brain plasticity, which are still not fully understood. Early exposure to a difficult postnatal environment together with early and unexpected removal from a protective milieu are exclusive and peculiar factors of prematurity that interfere with the normal development of the visual system in pre-term babies. The problem is further compounded by the influence of different perinatal brain lesions affecting the developing brain of premature babies. Nevertheless, in the last few decades, there have been considerable advances in our understanding of the development of vision in pre-term infants during early infancy. This has mainly been due to the development of age-specific tests assessing various aspects of visual function, from ophthalmological examination to more cortical aspects of vision, such as the ability to process orientation or different aspects of visual attention . Improvements in understanding very early and specific neurological impairments in neurological functions have been reported in pre-term infants, known to be at risk of developing visual and visual-perceptual impairment. These impairments are due not only to retinopathy, a common finding in premature infants, but also to cerebral (central) visual impairment, secondary to brain lesions affecting the central visual pathway. [Copyright &y& Elsevier]