Infant Cognitive Development Research Articles

EEG complexity as a biomarker for autism spectrum disorder risk

BackgroundComplex neurodevelopmental disorders may be characterized by subtle brain function signatures early in life before behavioral symptoms are apparent. Such endophenotypes may be measurable biomarkers for later cognitive impairments. The nonlinear complexity of electroencephalography (EEG) signals is believed to contain information about the architecture of the neural networks in the brain on many scales. Early detection of abnormalities in EEG signals may be an early biomarker for developmental cognitive disorders. The goal of this paper is to demonstrate that the modified multiscale entropy (mMSE) computed on the basis of resting state EEG data can be used as a biomarker of normal brain development and distinguish typically developing children from a group of infants at high risk for autism spectrum disorder (ASD), defined on the basis of an older sibling with ASD.MethodsUsing mMSE as a feature vector, a multiclass support vector machine algorithm was used to classify typically developing and high-risk groups. Classification was computed separately within each age group from 6 to 24 months.ResultsMultiscale entropy appears to go through a different developmental trajectory in infants at high risk for autism (HRA) than it does in typically developing controls. Differences appear to be greatest at ages 9 to 12 months. Using several machine learning algorithms with mMSE as a feature vector, infants were classified with over 80% accuracy into control and HRA groups at age 9 months. Classification accuracy for boys was close to 100% at age 9 months and remains high (70% to 90%) at ages 12 and 18 months. For girls, classification accuracy was highest at age 6 months, but declines thereafter.ConclusionsThis proof-of-principle study suggests that mMSE computed from resting state EEG signals may be a useful biomarker for early detection of risk for ASD and abnormalities in cognitive development in infants. To our knowledge, this is the first demonstration of an information theoretic analysis of EEG data for biomarkers in infants at risk for a complex neurodevelopmental disorder.

Maternal Docosahexaenoic Acid Supplementation Decreases Lung Inflammation in Hyperoxia-Exposed Newborn Mice1,2

DHA is a long-chain fatty acid that has potent antiinflammatory properties. Whereas maternal DHA dietary supplementation has been shown to improve cognitive development in infants fed DHA-supplemented milk, the antiinflammatory effects of maternal DHA supplementation on the developing fetus and neonate have not been extensively explored. Pregnant C3H/HeN dams were fed purified control or DHA-supplemented diets (~0.25% of total fat) at embryonic d 16 and consumed these diets throughout the study. At birth, the nursing mouse pups were placed in room air (RA; 21% O(2)) or >95% O(2) (hyperoxia) for up to 7 d. These studies tested the hypothesis that maternal DHA supplementation would decrease inflammation and improve alveolarization in the lungs of newborn mouse pups exposed to hyperoxia. Survival, inflammatory responses, and lung growth were compared among control diet/RA, DHA/RA, control/O(2), and DHA/O(2) pups. There were fewer neutrophils and macrophages in lung tissues from pups nursed by DHA-supplemented dams than in those nursed by dams fed the control diet at 7 d of hyperoxia exposure (P < 0.015). Although differences due to hyperoxia exposure were observed, maternal diet did not affect keratinocyte-derived chemokine, macrophage inflammatory protein-2, IL-1β, or TNFα mRNA levels in pup tissues. Hyperoxia also induced NF-κB activity, but maternal diet did not affect NF-κB or PPARγ activities. In mice, DHA supplementation decreases leukocyte infiltration in the offspring exposed to hyperoxia, suggesting a potential role for DHA supplementation as a therapy to reduce inflammation in preterm infants.

A prospective study of maternal anxiety, perceived stress, and depressive symptoms in relation to infant cognitive development

A prospective study of maternal anxiety, perceived stress, and depressive symptoms in relation to infant cognitive development

Infant mental health: provision of service by a lone practitioner in a non-clinical setting

This article describes the author's experience at a child-care centre whose staff focused on the achievement of developmental milestones and the cognitive development of infants, but with minimal attention paid to their internal lives. The author elucidates the complexity of clinical work in non-clinical settings and demonstrates how a psychoanalytic perspective along with an understanding of formal consultation helped her address barriers to clinical work. The establishment of a collaborative consulting relationship with a teacher of one of the infant classes enabled the author to intervene with some of the infants, and helped the teacher to gain an understanding and appreciation of infant mental processes. Specific interventions are described.

Infant ERP amplitudes change over the course of an experimental session: Implications for cognitive processes and methodology

Event-related Potentials (ERP) studies are a widely used methodology to investigate the early cognitive development in infants of all age ranges. We examined changes in amplitude contribution in a set of previously published data (see [4]) in relation to the Negative component as a function of number of trials contributing to each individual average and with time as a co-variate to that contribution. With only seven trials contributing to each individual’s average the Nc for the object-directed condition was significantly more negative than the one for the averted-gaze condition, which is the opposite of the effect reported in Hoehl et al. [4]. The analysis including time as a co-variate revealed that the effect did not alter according to the amount of time taken during the experiment to collect each trial, suggesting that data of the quality needed to contribute to the ERP is itself a measure of time varying components of the experimental session. We conclude that infants initially allocate more attentional resources to object-directed gaze. This suggests that the temporal dynamics of infant ERP violates assumptions present in adult ERP, and that differences between conditions in relatively few trials inform us of cognitive capacities during infancy.

Growth, neurological and cognitive development in infants with a birthweight &lt;501 g at age 5 years

To determine growth, neurological and cognitive development at 5 years of preterm infants with birthweights <501 g born in three German tertiary perinatal centres between 1998 and 2001. Structured neurological examination, the Gross Motor Function Classification Scale and the Kaufman-Assessment-Battery Test for Children. Of 107 infants, 48 received immediate life support (gestational age 25.2 weeks [21-30.7]; birth weight 435 g [290-500]) median [range]), 27 (56%) survived until follow-up [95% CI 39-69%], 19 (70%) could be tested. In few infants had catch-up growth taken place. Neurological test results were normal in five infants (26%) and mildly abnormal/severely abnormal in 11 (58%)/3 (16%) infants. Visual impairment was present in eight (42%), and hearing disability in three (16%). The mean mental processing composite (IQ) was 82 [50-104] (median [range]). Of all resuscitated infants with a birthweight <501 g, 56% survived to school age. Of these, composite outcome score showed normal development or mild disability in one-half, and moderate or severe disability in the other half of them. Investigators should include such infants in studies and their reports should give specific information about them.

Little Evidence of Association Between Severity of Trigonocephaly and Cognitive Development in Infants With Single-Suture Metopic Synostosis

To measure severity of trigonocephaly among infants with single-suture metopic craniosynostosis by using a novel shape descriptor, the trigonocephaly severity index (TSI), and to evaluate whether degree of trigonocephaly correlates with their neurodevelopmental test scores. We conducted a multicenter cross-sectional and longitudinal study, identifying and recruiting 65 infants with metopic synostosis before their corrective surgery. We obtained computed tomography images for 49 infants and measured the presurgical TSI, a 3-dimensional outline-based cranial shape descriptor. We evaluated neurodevelopment by administering the Bayley Scales of Infant Development, Second Edition, and the Preschool Language Scale, Third Edition, before surgery and at 18 and 36 months of age. We fit linear regression models to estimate associations between test scores and TSI values adjusted for age at testing and race/ethnicity. We fit logistic regression models to estimate whether the odds of developmental delay were increased among children with more severe trigonocephaly. We observed little adjusted association between neurodevelopmental test scores and TSI values, and no associations that persisted at 3 years. Trigonocephaly was less severe among children referred at older ages. We observed little evidence of an association between the severity of trigonocephaly among metopic synostosis patients and their neurodevelopmental test scores. Detecting such a relationship with precision may require larger sample sizes or alternative phenotypic quantifiers. Until studies are conducted to explore these possibilities, it appears that although associated with the presence of metopic synostosis, the risk of developmental delays in young children is unrelated to further variation in trigonocephalic shape.

Visual attention performance in term born and preterm infants with different perinatal risk

Study aim: Preterms are undoubtly at high risk for cognitive developmental delay and impairment. Early assessment is crucial but lacks of reliable and valid procedures. Attention, processing speed and recognition memory are relevant aspects of cognitive development in infancy, thus respective paradigms are of high importance for early diagnosis. The present study investigates the practicability and informative value of a visual habituation-dishabituation-task with categorial stimuli (Pahnke & Pauen, 2006). Methods: Visual speed of processing and memory was assessed in 30 preterms with birth weight 1500g and 30 term borns. In the visual categorization task infants were familiarized with 10 similar looking abstract geometric stimuli and were then tested with another stimulus of contrasting shape and color. As dependent variables different measures of looking duration, strength of habituation and strength of dishabituation were examined. Global development was assessed with a developmental test (Bayley-II), sex and school graduation of parents were controlled for. Results: Data collection has been completed. Preliminary analyses show significant longer total looking times during habituation for preterms with very low birth weight compared to term born infants (Z=–2.00, p<0.05). Data of preterms with higher birth weight are currently coded. Looking times of these infants seem to differ from those of term borns as well. Correlation analyses of looking duration with developmental test scores are in progress. Discussion: Results suggest that total looking time – indicating speed of processing – might play a key role for explaining differences in cognitive performance of preterm and term born infants. Longer looking times seem to be linked with worse cognitive performance in preterms. Future analyses are necessary in order to prove reliability of this assessment procedure and enhance clinical use.

Early infant cognitive assessment:

The present study represents a contribution to the assessment of infant cognitive development by presenting a valid instrument for observing the development of logical reasoning and executive function during the second year of life-key processes in the construction of human knowledge. The instrument constructed, called ELEDA (Early Logical and Executive Development Assessment), was a combined or mixed observation instrument composed of field formats and category systems. Its validity was calculated using generalizability theory, which enables different sources of error affecting a behavioral measurement to be analyzed jointly. The need for valid early cognitive assessment instruments such as the one in the present article is evident, since the sooner assessment is performed, the sooner action can be taken, thus optimizing the results.

Developmental stimulation in child care centers contributes to young infants’ cognitive development

This study examined whether the quality of caregiver behavior in child care centers contributes to infant cognitive development at 9 months of age. Sixty-four infants (34 boys) were observed with their primary caregivers in child care centers at 3, 6, and 9 months of age. Caregiver behavior was rated for sensitivity and for stimulation of infant development during one-to-one caregiving interactions. Infant cognitive development was assessed using the Bayley Scales of Infant Development-II (Mental Development Index). Higher levels of developmental stimulation in the centers predicted higher levels of infant cognitive development at 9 months, beyond infant cognitive development at 3 months (just before entering child care), parental education, and maternal sensitivity. The results suggest that even small increases in developmental stimulation provided in child care centers in the first year of life may foster infants’ cognitive development.

Neurodevelopmental effects of prenatal exposure to psychotropic medications

Until now, studies on the reproductive safety of psychotropics have typically assessed the risk of congenital malformations and perinatal complications associated with in utero exposure to such medications. However, little is known of their inherent potential neurobehavioral teratogenicity. The objective is to analyze available data from studies investigating developmental outcome of children exposed prenatally to psychotropics. A computerized Medline/PubMed/TOXNET/ENBASE search (1960-2010) was conducted using the following keywords: pregnancy, child/infant development/neurodevelopment, antidepressants, benzodiazepines, mood stabilizers, and antipsychotics. A separate search was also run to complete the safety profile of single specific medications. Resultant articles were cross-referenced for other relevant articles not identified in the initial search. A noncomputerized review of pertinent journals and textbooks was also performed. All studies published in English and reporting primary data on the developmental outcome of infants exposed in utero to psychotropics and born without malformations were collected. As regards antiepileptic drugs, only studies that provided data on specific medications approved for psychiatric practice use (carbamazepine, lamotrigine, and valproate) were considered. Data were extracted from 41 articles (38 identified electronically and 3 nonelectronically), which met the inclusion criteria. Despite reviewed studies showing relevant methodological limitations, concordant, albeit preliminary, information seems to exclude that prenatal exposure to both selective serotonin reuptake inhibitors and tricyclic antidepressants may interfere with the infants' psychological and cognitive development. Conversely, information on valproate strongly discourages its use in pregnant women. Moreover, although data on carbamazepine remain controversial, information on whole classes of drugs and single medications is either absent (second-generation antipsychotics) or too limited (first-generation antipsychotics, benzodiazepines, lithium, and lamotrigine) to inform the decision-making process. For all classes of psychotropics, new and/or further studies are warranted to answer definitively the urgent question about the impact of prenatal exposure to such medications on infant development.

Psychological support for parents in UK tertiary-level neonatal units—a postcode lottery

<h3>Background and Aim</h3> Neonatal intensive care units (NICUs) are high stress environments for parents and staff. A high prevalence of post-traumatic stress in parents exists, often persisting for years. Maternal anxiety affects infant cognitive and socio-emotional development assessed at 24 months corrected age. The authors aimed to assess current psychological and social support available for parents in UK tertiary-level NICUs. <h3>Methods</h3> Telephone survey in August 2009 of all 50 tertiary-level NICUs in the UK. The authors asked the senior nurse/nurse manager what formal psychological support, if any, was provided to parents on their NICU, and whether their unit had dedicated social work input. <h3>Results</h3> The authors obtained information from all 50 (100%) units. Two units (4%) had dedicated clinical psychologists for their NICU who provided comprehensive support for parents and offered regular meetings and counselling sessions; a further 15 units (30%) had the support of an available clinical psychologist who provided input to both the NICU and maternity unit as required; 13 units (26%) offered some psychological support, though not from a trained psychologist (eg, offered by a trained counsellor nurse/family care nurse, a parental support group, bereavement counsellor or hospital chaplain); in 20 (40%) units no psychological support was available for parents. Regarding social work support for the NICU, 20 (40%) units had regular input from a social worker, either in terms of them joining the clinical ward round or attending a weekly psychosocial meeting. Time allocated for the dedicated social worker support ranged from a few hours per week to a full time social worker based in the unit. Five (10%) units held a weekly social ward round. The majority of NICUs (30/50; 60%) did not have either a dedicated social worker, or any regular meeting between nurses/doctors and social worker to discuss the social needs of parents/families. <h3>Conclusion</h3> Some NICUs offer parents excellent psychological support, while many other NICUs offer parents no formal psychological support whatsoever. The psychological and social needs of many parents with babies on UK neonatal units are presently not being addressed, and this may have adverse long-term consequences for infants and their families.

Infant Sleep and Cognitive Development

Sleep is as vital to good health as water and nutrition. Disrupted sleep has a strong association with reduced cognitive abilities in children.

Maternal Prenatal Cortisol and Infant Cognitive Development: Moderation by Infant–Mother Attachment

Experimental animal studies suggest that early glucocorticoid exposure may have lasting effects on the neurodevelopment of the offspring; animal studies also suggest that this effect may be eliminated by positive postnatal rearing. The relevance of these findings to humans is not known. We prospectively followed 125 mothers and their normally developing children from pregnancy through 17 months postnatal. Amniotic fluid was obtained at, on average, 17.2 weeks gestation; infants were assessed at an average age of 17 months with the Bayley Scales of Infant Development, and ratings of infant-mother attachment classification were made from the standard Ainsworth Strange Situation assessment. Prenatal cortisol exposure, indexed by amniotic fluid levels, negatively predicted cognitive ability in the infant, independent of prenatal, obstetric, and socioeconomic factors. This association was moderated by child-mother attachment: in children with an insecure attachment, the correlation was [r(54) = -.47, p < .001]; in contrast, the association was nonexistent in children who had a secure attachment [r(70) = -.05, ns]. These findings mimic experimental animal findings and provide the first direct human evidence that increased cortisol in utero is associated with impaired cognitive development, and that its impact is dependent on the quality of the mother-infant relationship.

Infants' Physical and Cognitive Development After International Adoption From Foster Care or Institutions in China

To compare the physical, cognitive, and motor development of infants adopted from foster care with infants adopted from institutions. Forty-two formerly fostered and 50 post-institutionalized girls adopted from China, aged between 11 and 16 months on arrival, were visited 2 and 6 months after adoption. Children's height, weight, and head circumference were measured. Stress regulation was assessed by diurnal salivary cortisol levels, and cognitive and motor development were assessed using the Bayley Scales of Infant Development-second edition. At both assessments, the (modest) physical growth delays were similar for formerly fostered and post-institutionalized children. For weight and head circumference (but not for height) a catch-up over time was found, with a significant interaction between time and age at arrival, showing a more rapid catch-up for earlier adopted children. The daily cortisol curves of the formerly fostered and post-institutionalized children were similar and did not change over time. At both assessments, the former foster children outperformed the post-institutionalized children on mental and motor skills. Both groups showed a similar catch-up for mental development. For motor development, no catch-up was found. The influence of pre-adoption foster versus institutional rearing seems more pronounced for cognitive and motor development than for physical development and hormonal stress regulation. Our outcomes suggest that pre-adoption foster care is less detrimental to children's cognitive and motor development than institutional rearing.

Infant Temperament, Maternal Personality, and Parenting Stress as Contributors to Infant Developmental Outcomes

This study examined contributions of maternal personality and infant temperament to infant vocabulary and cognitive development both directly and indirectly through parental stress. Participants were recruited at birth and included 63 infant twin pairs and their mothers. Assessments were completed at 6, 9, 12, and 18 months of age and included Dimensions of Temperament–Revised (maternal personality), Parenting Stress Index (parental stress), Infant Behavior Questionnaire–Revised (infant temperament), Bayley Scales of Infant Development II: Mental Development Index, and MacArthur-Bates Total Vocabulary. Structural equation modeling with a jackknife approach was used to analyze data separately for each twin in the pair. At 12 months, maternal personality and infant temperament contributed indirectly to MacArthur-Bates Total Vocabulary and Bayley Mental Development Index scores through parental stress. In addition, infant temperament directly contributed to 12-month MacArthur-Bates Total Vocabulary. At 18 months, these relationships were no longer significant. The different findings at 12 months compared to 18 months may reflect important developmental and environmental shifts, as well as possible differences in the method and measurements used at each age.

The Timing of Prenatal Exposure to Maternal Cortisol and Psychosocial Stress Is Associated With Human Infant Cognitive Development

The consequences of prenatal maternal stress for development were examined in 125 full-term infants at 3, 6, and 12 months of age. Maternal cortisol and psychological state were evaluated 5 times during pregnancy. Exposure to elevated concentrations of cortisol early in gestation was associated with a slower rate of development over the 1st year and lower mental development scores at 12 months. Elevated levels of maternal cortisol late in gestation, however, were associated with accelerated cognitive development and higher scores at 12 months. Elevated levels of maternal pregnancy-specific anxiety early in pregnancy were independently associated with lower 12-month mental development scores. These data suggest that maternal cortisol and pregnancy-specific anxiety have programming influences on the developing fetus.

Tactile stimulation in physically healthy infants: results of a systematic review

Touch establishes powerful physical and emotional connections between infants and their caregivers, and plays an essential role in development. The objective of this systematic review was to identify published research to ascertain whether tactile stimulation is an effective intervention to support mental and physical health in physically healthy infants. Twenty‐two studies of healthy infants with a median age of six months or less met our inclusion criteria. The limited evidence suggests that infant massage may have beneficial effects on sleeping and crying patterns, infants’ physiological responses to stress (including reductions in serum levels of norepinephrine and epinephrine, and urinary cortisol levels), establishing circadian rhythms through an increase in the secretion of melatonin, improving interaction between mother‐infant dyads in which the mother is postnatally depressed, and promoting growth and reducing illness for limited populations (i.e. infants in an orphanage where routine tactile stimulation is low). The only other evidence of a significant impact of massage on growth in infants living in families was obtained from a group of studies regarded to be at high risk of bias which we have reported separately. There is no evidence of a beneficial effect on infant temperament, attachment or cognitive development. There is, therefore, some evidence of benefits on mother‐infant interaction, sleeping and crying, and on hormones influencing stress levels. In the absence of evidence of harm, these findings support the use of infant massage in the community, particularly in contexts where infant stimulation is poor. Further research is needed, however, before it will be possible to recommend universal provision.

Perspectives on multisensory experience and cognitive development in infants with cochlear implants

Infants learn about their environment through sensory exploration, acquiring knowledge that is important for cognitive development. However, little is known about the sensory exploration of infants with profound hearing loss before or after they receive cochlear implants. This paper reviews aspects of sensory perception and cognitive development in hearing infants, discusses the implications of delayed access to auditory information for multisensory perception and cognitive development in infants who use cochlear implants, and suggests several new directions for research addressing multisensory exploration and cognitive development in infants with cochlear implants.

Longer duration of epilepsy and earlier age at epilepsy onset correlate with impaired cognitive development in infancy

We assessed the impact of age at onset of epilepsy and duration and frequency of seizures on cognitive development in children less than 3 years old. Retrospective analysis was conducted on clinical data and neuropsychological testing of 33 infants with epilepsy. Developmental quotients were calculated and were correlated with age at epilepsy onset, duration of epilepsy, seizure frequency, brain pathology, and types of seizures (with/without spasms) as potential predictors. Infants with longer duration and earlier onset of epilepsy performed worse on developmental neuropsychological testing. Regression analyses showed that age at epilepsy onset and percentage of life with epilepsy were both strongly associated (regression model P < 0.0001) with developmental quotient. There was no correlation with seizure frequency. Infants with spasms had worse developmental quotients than infants without spasms ( P < 0.001). These results suggest that duration of epilepsy and age at onset may be the best developmental predictors during the first years of life in patients with epilepsy. Early aggressive intervention should be considered.