Similarities and Differences in Behavioral State Organization during Sleep Periods in the Perinatal Infant Before and After Birth

The purpose of this study was to determine the degree of consistency in behavioral state organization for 30 low-risk human participants examined as fetuses at 38–40 weeks gestation and again as neonates at approximately 2 weeks postnatal age. behavioral states were assigned similarly for fetuses and neonmates in terms of heart rate pattern and the presence or absence of eye and gross body movements. We found that the time spent in a sleep period was distributed among quiet sleep (QS), active sleep (AS), and indeterminate states in virtually identical proportions for fetuses and neonates. However, the only within-subject consistency between the fetal and neonatal periods was in the duration of complete QS epochs. Fetuses made fewer transitions between QS and AS, but neonates had shorter and more structured AS → QS transitions. These findings suggest that, whereas central nervous system processes governing QS do not change appreciably, the control of AS undergoes significant changes in the 4 weeks spannig the fetal and neonatal periods. We believe that the duration of enclosed QS epochs provides the only stable measure of behavioral state development between the prenatal and postnatal periods.     

Ontogeny of long-term,nonassociative memory in the rat

The primary purpose of the present study was to assess the ontogeny of nonassociative learning and memory in 16-, 30-, and 75-day-old rats. In each of three experiments, habituation of the orienting response to a novel auditory stimulus was measured. The orienting response is an unconditioned reaction elicited by innocuous environmental stimulation that habituates with repeated stimulus presentations. Both an autonomic component (heart-rate deceleration) and a behavioral index (head jerk) of the orienting response were recorded in this study. Although no age differences in rate of habituation (i.e., rate of nonassociative learning) were found (see Experiment 1), a marked effect of age on retention of habituation was observed. Preweanling rats retained habituation of the orienting response to an auditory stimulus for less than 4 h (Experiment 2), whereas adult animals exhibited no forgetting even after a 1-week interval (Experiment 3). These results are discussed in terms of (1) demonstrations of age-related differences in associative memory, (2) the persistence of nonassociative memories in adults, and (3) the significance of the orienting response as a measure of retention of nonassociative learning.     

Maturation of Human Fetal Responses to Vibroacoustic Stimulation

Maturation of human fetal response to vibroacoustic stimulation was examined in 60 fetuses from 23 to 36 weeks gestational age. Subjects received vibroacoustic or no-stimulus control trials (randomly assigned) while fetal heart rate (FHR) was recorded and movement was observed on real-time ultrasound scan. Initially, at 26-28 weeks, a small FHR deceleration response occurred; subsequently, FHR acceleration responses occurred. From 29 weeks, 83%-100% of subjects responded with an FHR acceleration > or = 10 BPM on the first vibrator trial and accelerations were observed on 83%-92% of all vibrator trials. From 26 to 36 weeks the percentage of fetuses responding with movement on the first vibrator trial increased from 58% to 100%; on all vibrator trials responses increased from 53% to 94%. It was concluded that maturation of human fetal response to vibroacoustic stimulation begins at about 26 weeks gestation, increases steadily over a 6-week period, and reaches maturity at about 32 weeks.     

Infant behavior and development in relation to fetal movement and habituation

Fetal movement and habituation were examined in relation to behavior and development in early infancy. 39 fetuses were evaluated between 28 and 37 weeks gestation. A vibrating stimulus was repeatedly applied to the maternal abdomen until the fetus habituated (i.e., ceased moving in response). Fetal movements were observed on an ultrasound monitor by 2 observers who recorded their observations onto a strip chart. Using a median split, fetuses were placed into high- or low-movement groups and fast- or slow-habituating groups. The groups were compared after birth on the Brazelton Neonatal Behavior Assessment Scale and the Bayley Scales of Infant Development. Preliminary evidence is presented that fetal rate of habituation predicts some aspects of infant behavior and development.     

The Efficacy of Repeated Reading and Wide Reading Practice for High School Students with Severe Reading Disabilities

This experimental study was conducted to examine the efficacy of repeated reading and wide reading practice interventions for high school students with severe reading disabilities. Effects on comprehension, fluency, and word reading were evaluated. Participants were 96 students with reading disabilities in grades 9–12. Students were paired within classes and pairs were randomly assigned to one of three groups: repeated reading ( N  = 33), wide reading ( N  = 34), or typical instruction ( N  = 29). Intervention was provided daily for approximately 15–20 minutes for 10 weeks. Results indicated no overall statistically significant differences for any condition, with effect sizes ranging from −.31 to .27. Findings do not support either approach for severely impaired readers at the high school level. We hypothesize that these students require more intensive interventions that include direct and explicit instruction in word- and text-level skills as well as engaged reading practice with effective feedback.     

Children's Memory of an Occurrence of a Repeated Event: Effects of Age, Repetition, and Retention Interval across Three Question Types

Children's memory of the final occurrence of a repeated event was examined whereby each occurrence had the same underlying structure but included unpredictable variations in the specific instantiations of items across the series. The event was administered by the children's teachers at the kindergarten or school. The effects of repetition (single vs. repeated event), age (4–5 vs. 6–8-year-olds), retention interval (1 week vs. 6 weeks), and the frequency of specific instantiations of items were examined across 3 question types. Repetition increased the number of items recalled on a level that was common to all occurrences in response to general probes and reduced the likelihood that children would report details that did not occur in the event. However, repetition also reduced the number of correct responses about which instantiation was included in the occurrence and decreased the consistency of responses across repeated questioning. Most errors were intrusions of details from other occurrences; usually references to instantiations of items that had occurred frequently throughout the series. The younger children showed a poorer ability to discriminate between the occurrences than the older children, but age differences were less evident at the longer retention interval. The results are discussed in relation to current theories of memory and children's eyewitness testimony.     

Prenatal Antecedents of Newborn Neurological Maturation

Fetal neurobehavioral development was modeled longitudinally using data collected at weekly intervals from 24 to 38 weeks gestation in a sample of 112 healthy pregnancies. Predictive associations between 3 measures of fetal neurobehavioral functioning and their developmental trajectories to neurological maturation in the first weeks after birth were examined. Prenatal measures included fetal heart rate (FHR) variability, fetal movement, and coupling between fetal motor activity and heart rate patterning; neonatal outcomes include a standard neurologic examination ( n  =   97) and brainstem auditory evoked potential (BAEP; n  =   47). Optimality in newborn motor activity and reflexes was predicted by fetal motor activity, FHR variability, and somatic–cardiac coupling predicted BAEP parameters. Maternal pregnancy-specific psychological stress was associated with accelerated neurologic maturation.     

Relationships between reading,phonological skills and language development in individuals with Down syndrome: A five year follow-up study

This article is based on language, memory andreading information gathered for a five yearfollow-up study of 30 children and adolescentswith Down syndrome, aged from 10 to 24 years atthe end of the study. At Time 1, 10individuals were classified as readers but byTime 2 this number had risen to 16. Readers significantly outperformed non-readerson tests of nonverbal ability, languagecomprehension and production, phonologicalmemory and phonological awarenesss. However,some of these differences could be accountedfor by readers' significantly lower hearingthresholds. Phonological memory and earlyletter knowledge at Time 1 were significantpredictors of reading scores for Time 2readers, after controlling for age, nonverbalability and corresponding Time 1 readingscores. There was no evidence that learning toread had a significant impact on later languagecomprehension, but early reading skills may besignificant predictors of MLU five years later,after controlling for age, nonverbal abilityand hearing.     

Predicting the Growth of Early Spelling Skills: Are There Heterogeneous Developmental Trajectories?

We examined the growth of spelling skills in a large sample of Norwegian children (N = 228) over the first 3 years in school. The roles of phoneme awareness, letter knowledge, rapid automatized naming (RAN), visual–verbal paired-associate learning, and verbal short-term memory as predictors of later spelling skills were examined. Phoneme awareness and letter knowledge together with nonalphanumeric RAN and verbal short-term memory were independent longitudinal predictors of both word and nonword spelling. In addition growth mixture modeling suggested that individual variations in the growth of word spelling were best characterized as variations around a single trajectory, whereas growth in nonword spelling was better characterized as variations around two distinct trajectories. The results are related to current theories about the cognitive and linguistic foundations of spelling.     

A Meta-Analysis of Infant Habituation and Recognition Memory Performance as Predictors of Later IQ

A meta-analytic review of the literature on infant habituation and recognition memory performance as predictors of later IQ suggests several conclusions: (1) Habituation and recognition memory assessments made on a variety of risk and nonrisk samples in the first year of life predict later IQ assessed between 1 and 8 years of age with a weighted (for N ) average of normalized correlations of .36 or a raw median correlation of .45. (2) The size of the predictive correlation is essentially the same for habituation and for recognition memory paradigms. (3) This prediction phenomenon is not obviously associated solely with one laboratory, one particular infant response measure, or a few extremely disordered infants. (4) The level of prediction to childhood IQ is substantial given the reliability of the infant measures. (5) Predictions are somewhat higher for risk than for nonrisk samples. (6) Predictions are consistently higher than for standardized infant tests of general development for nonrisk but not for risk samples, and they are not consistently higher than predicting from parental education and socioeconomic status or a few other infant behaviors for nonrisk samples. (8) Coefficients may be higher when the predicting assessments are made between 2 and 8 months of age than earlier or later, but prediction coefficients are remarkably consistent across the observed outcome age period of 2–8 years.     

Effects of violent and non-violent computer game content on memory performance in adolescents

The present study focuses on the short-term effects of electronic entertainment media on memory and learning processes. It compares the effects of violent versus non-violent computer game content in a condition of playing and in another condition of watching the same game. The participants consisted of 83 female and 94 male adolescents with a mean age of 17.6 years. The dependent variables are memory for previously learnt verbal and visual material, memory for media-related content and physiological measures of stress (heart rate, cortisol, salivary alpha-amylase). Besides the group comparisons, potential mediation effects and gender differences were examined. The results show that violent content leads to a poorer memory performance for verbal material and to an increased heart rate. The heart rate, however, does not mediate the effect on memory performance. Genders differ regarding their abilities to memorise verbal and visual material, with females showing a better performance (independent of the experimental condition), and for memorising media-contents, where the males outperform females (also independent of experimental condition). The study supports the assumption that violent and arousing media content has a negative short-term effect on simultaneous information processing and learning and that there are gender-specific media effects.     

Is disfluency desirable for learning?

While some difficult learning conditions can improve learning, the findings regarding the contribution to learning of disfluent, hard-to-read text materials have been inconsistent. We identified test delay and disfluency manipulations as factors potentially contributing to these discrepancies. We tested students' immediate and delayed memory performance (2 weeks later) on a course text that was presented between-subjects (N = 134) either as perceptually disfluent with a hard-to-read-font, as lexically disfluent with 20% scrambled letters, or in its original format. By distinguishing between short-term and long-term learning, our expectations were supported; an illegible font reduced forgetting, thereby producing delayed memory benefits. We also tested whether lexical disfluency would have similar memory effects as perceptual disfluency, as the meta-cognitive perspective suggests, or whether different disfluency manipulations would have different memory effects, as ideas from a contextualized framework on desirable difficulties suggests. The findings supported the latter. The results are discussed regarding the generalizability of the disfluency effects and the implications for when disfluency is desirable.     

A Longitudinal Investigation of Chimpanzees' Understanding of Visual Perception

Seven chimpanzees were tested for their understanding of the intentional aspect of visual perception at 5 – 6 years of age and again at 7 years of age. They appeared not to understand that they should use a species-typical, visually based begging gesture in front of someone who could see them, as opposed to someone who could not. Four experiments that were conducted when these same subjects were adolescents are reported here. The results suggest that there was no development between 5 and 9 years of age in the animals' understanding of visual perception as an internal state of attention. The subjects appeared to learn procedural, stimulus-based rules related to the frontal orientation, the face, and the eyes of the experimenters. Even subjects most adept at these tasks appeared to rely on stimulus-based rule structures, not an attribution of "seeing."     

The Relations Between Children’s Reading Comprehension, Working Memory, Language Skills and Components of Reading Decoding in a Normal Sample

The primary aim of the current study was to identify the strongest independent predictors of reading comprehension using word reading, language and memory variables in a normal sample of 180 children in grades 3–5, with a range of word reading skills. It was hypothesized that orthographic processing, receptive vocabulary and verbal working memory would all make independent contributions to reading comprehension. The contributions of reading speed, receptive grammatical skills, exposure to print, visuospatial working memory and verbal learning and retrieval (a measure of longer-term retention) were also investigated. Working memory tasks that required the processing and storage of numerical and spatial material were used. One of the numerical working memory tasks was based on the number span task developed by Yuill, Oakhill, and Parkin British Journal of Psychology, 1989, 80, 351–361. A visuospatial equivalent of that task was developed from the forward Corsi block task [Corsi, Abstracts International, 1973, 34, 891]. The results revealed that, after controlling for age and general intellectual ability, the word reading and the language variables had a much stronger relation with reading comprehension than the memory variables. The strongest independent predictor of reading comprehension was orthographic processing since it captured variance in both word reading, language skills and verbal working memory. The forward Corsi task and performance on a measure of verbal learning and retrieval each made small independent contributions to reading comprehension but the contribution of verbal working memory was not significant. It was concluded that tasks measuring the interplay between short-term and long-term memory, in which new information is combined with information already stored in long-term memory, may better predict reading comprehension measured with the text available than working memory tasks which only have a short-term memory component.     

Cognitive and Neural Development of Individuated Self-Representation in Children

Processing the self-relevance of information facilitates recall. Similarly, processing close-other-related information facilitates recall to a lesser degree than processing self-relevant information. This memory advantage may be viewed as an index of the degree to which the representation of self is differentiated from representations of close others. To test developmental hypotheses concerning the self, this study examined the relation of memory for self- and mother-referentially processed information in participants age 7–13 years (Experiment 1: N  = 37; Experiment 2: N  = 14). Memory for words encoded with reference to oneself increases with age, relative to memory for words encoded with reference to one's mother. When used as an individual difference measure, the difference in self versus mother memory correlates with regions of the rostral anterior cingulate associated with affective salience.     

Does Higher Quality Early Child Care Promote Low‐Income Children’s Math and Reading Achievement in Middle Childhood?

Higher quality child care during infancy and early childhood (6–54 months of age) was examined as a moderator of associations between family economic status and children's ( N  = 1,364) math and reading achievement in middle childhood (4.5–11 years of age). Low income was less strongly predictive of underachievement for children who had been in higher quality care than for those who had not. Consistent with a cognitive advantage hypothesis, higher quality care appeared to promote achievement indirectly via early school readiness skills. Family characteristics associated with selection into child care also appeared to promote the achievement of low-income children, but the moderating effect of higher quality care per se remained evident when controlling for selection using covariates and propensity scores.     

Contemporaneous and Longitudinal Prediction of Children's Social Functioning from Regulation and Emotionality

Relations of regulation and emotionality to social functioning were examined for 77 children followed from early to middle school age. Parents and teachers reported on children's social behavior, emotionality, and regulation, and children engaged in analogue peer conflict situations (i.e., with puppets). High-quality social functioning was predicted by high regulation and low levels of nonconstructive coping, nevatige emotionality, and general emotional intensity. Prediction often was obtained across reporters and time, although prediction was strongest within context (home versus school). Moreover, measures of regulation and emotionality frequently contributed unque variance to the prediction of social functioning. Contemporaneous correlations at age 8–10 were similar to those obtained at age 6–8, and prediction of later social functioning from emotionality and regulation at age 4–6 was similar at ages 6–8 and 8–10.     

Working memory and learning in children with developmental coordination disorder and specific language impairment

The authors compared 6- to 11-year-olds with developmental coordination disorder (DCD) and those with specific language impairment (SLI) on measures of memory (verbal and visuospatial short-term and working memory) and learning (reading and mathematics). Children with DCD with typical language skills were impaired in all four areas of memory function for their age level, and this pattern was also found to be characteristic of a larger DCD group with varied language abilities. SLI-group deficits in standard scores were observed for the verbal versions of the short-term and working memory tasks only. There were also differential links between memory and attainment between the two groups, with visuospatial working memory strongly related to numeracy in the SLI group and all of the memory measures correlated with at least one attainment measure in the DCD group. Reasons for why working memory contributes to learning in these two developmental groups are discussed.     

The stability of visual habituation during the first year of life

The short-term reliability and long-term stability of visual habituation and dishabituation in infancy were assessed in a sample of 186 infants from 4 age groups (3-, 4-, 7-, and 9-month-olds) seen for 2 within-age sessions and in a sample of 69 infants seen longitudinally at 3, 4, 7, and 9 months of age. Moderate week-to-week reliability (r's = .30-.50) was observed for duration-based and magnitude of habituation variables at all ages, although better reliability was evident at 4 and 9 months than at 3 and 7 months. In most cases, the reliability of habituation magnitude measures was attributable to the reliability of the peak fixation alone. Data from the longitudinal sample suggested that only the duration of peak fixation was consistently stable across the ages tested, although stability for several measures emerged across the 7-9-month testing. No consistent reliability or stability emerged for the presence or magnitude of dishabituation in either sample.     

Fetal Neurobehavioral Development

The ontogeny of fetal autonomic, motoric, state, and interactive functioning was investigated longitudinally in a sample of 31 healthy fetuses from 20 weeks through term. Fetal heart rate and movement data were collected during 50 min of Doppler-based fetal monitoring at 6 gestational ages. Measures of fetal heart rate and variability, activity level and vigor, behavioral state, and reactivity were derived from these digitized data. Weighted least squares analyses were conducted to model the developmental patterns and to examine the role of maternal and fetal covariates. With advancing gestation, fetuses displayed slower heart rate, increased heart rate variability, reduced but more vigorous motor behavior, coalescence of heart rate and movement patterns into distinct behavioral states, and increasing cardiac responsivity to stimulation. Male fetuses were more active than female fetuses, and greater maternal stress appraisal was associated with reduced fetal heart rate variability. An apparent period of neurobehavioral transition exists between 28 and 32 weeks. Fetal research methods are evaluated.