Research indicates that infants lose the capacity to perceive distinctions in nonnative sounds as they become sensitive to the speech sounds of their native language (i.e., by 10- to 12-months of age). However, investigations into the decline in nonnative phonetic perception have neglected to examine the role of non-linguistic information. Exaggerated prosodic intonation and facial input are prominent in the infants' language-learning environment, and both have been shown to ease the task of speech perception. The current investigation was designed to examine the impact of infant-directed (ID) speech and facial input on infants' ability to discriminate phonemes that do not contrast in their native language. Specifically, 11-month-old infants were tested for discrimination of both a native phoneme contrast and a nonnative phoneme contrast across four conditions, including an auditory manipulation (ID speech vs. AD speech) and a visual manipulation (Face vs. Geometric Form). The results indicated that infants could discriminate the native phonemes across any of the four conditions. Furthermore, the infants could discriminate the nonnative phonemes if they had enhanced auditory and visual information available to them (i.e., if they were presented in ID speech with a synchronous facial display), and if the nonnative discrimination task was the infants' first test session. These results suggest that infants do not lose the capacity to discriminate nonnative phonemes by the end of the first postnatal year, but that they rely on certain language-relevant and non-linguistic sources of information to discriminate nonnative sounds. / Ph. D.

One of the most intriguing and enduring issues in contemporary developmental cognitive neuroscience centers on the development of the ability to remember past experiences and the neural systems which support this capacity. Over the past 25 years, through methodological advancements and direct challenges to established assumptions, the focus of this developmental question has shifted to highlight the second half of the first year of life as the time when true explicit memory functionally emerges and begins to rapidly develop. The purpose of the following study was to test specific hypotheses regarding the biobehavioral development of explicit memory during infancy and present a new approach to studying the behavioral and physiological expression of this system. This study, which was guided by hypothesized neural substrates of this memory system, is the first direct investigation of continuous brain electrical activity during both the encoding and retrieval phases of explicit memory processing in infants. Memory-related differences in behavior and task-related brain activity in individual cortical areas were of particular interest. The results of this study provided some support for the hypothesis that baseline-to-task changes in EEG power can distinguish between successful and unsuccessful ordered-recall memory. Specifically, decreases in brain-electrical activity relative to a baseline period were found at both frontal and temporal locations during stimulus encoding and retrieval for infants who failed the recall tests. However, either no change, or increases in EEG power at frontal and temporal sites was related to successful performance on this task. In addition, different patterns of brain-electrical activity were present for correct and incorrect responses from the same child. This study contributes to our understanding of the biobehavioral expression of infant explicit memory in three main ways. First, changes in both frontal and temporal lobe activity are directly involved in explicit memory processing both during event encoding as well as retrieval. Second, this work provides evidence of a developmentally appropriate and valid pattern of electrophysiology specific to explicit memory processing. Finally, this study bridges the gap between a classic behavioral task of infant memory (which has been conceptually linked to neuropsychological data) and current developmental cognitive neuroscience. / Ph. D.

The present study was designed to investigate the development of infants' recognition of their fathers, specifically examining the role of multisensory information (visual and auditory cues). All infants were 4-months-old and were tested in a visual-fixation preference procedure. The two measures of interest were attention and affective responsiveness. Preference was measured by the amount of time the infants watched a visual stimulus. In Experiments 1 and 2 this stimulus was the paternal face. In Experiment 2 the paternal face was also accompanied by the paternal voice. In Experiment 3, the stimulus was the maternal face plus voice. Affective responsiveness was coded for hedonic tone, interest and excitement. It was found that infants showed more positive affect towards their fathers' faces (Experiment 1) and faces plus voices (Experiment 2), p < .05. In Experiment 3, results showed that infants preferred their mothers' faces plus voices over an unfamiliar female face plus voice when the first trial was excluded from the analysis, p < .05. These findings not only support the literature on infants' recognition of their mothers, but they also contribute to the increasing body of information on infants and their fathers. The findings are interpreted as supporting the hypothesis that the developmental pattern of father recognition is qualitatively and quantitatively different from that of mother recognition. / Ph. D.

This project examines two organizations--the Better Babies Bureau and the Children's Bureau--created by Progessive women in the early twentieth century to combat high infant mortality rates, improve prenatal and postnatal care, and better child welfare. The Better Babies Bureau, founded in 1913 by journalists from the Woman's Home Companion magazine, and the Children's Bureau, founded as a federal agency in 1912, used similar campaigns to raise awareness of these child welfare problems in the early 1900s; where they differed, however, is in their ultimate goals. The Children's Bureau sought to improve long-term medical care and infant mortality rates for women regardless of race or socioeconomic status; I analyze how they worked directly with midwives and health officials to provide better care for mothers and children. The Better Babies Bureau, in comparison, catered specifically to white women through prize-based contests and eugenics rhetoric. Through their better baby contests, they promoted the idea that disabilities and defects should be eliminated in children in order to create a better future. By the late 1910s, these two organizations were utilizing nationwide campaigns to appeal to mothers through either consumerism or health conferences. I argue that although the Better Babies Bureau made a greater cultural impact, the Children's Bureau made a longer lasting—and farther reaching—impact on infant mortality rates by making healthcare more accessible for both rural and urban women. / Master of Arts / In the early twentieth century, many Americans became concerned with the number of children dying before age one. This thesis examines two different organizations that were created in an attempt to reduce these infant mortality rates, improve prenatal and postnatal care, and better child welfare. These two organizations, the Children's Bureau and the Better Babies Bureau, were created and run by Progressive women who took vastly different approaches to raising awareness of these problems. The Children's Bureau worked directly with health and government officials to improve child welfare and healthcare. Meanwhile, the Better Babies Bureau utilized contests to convince mothers that defects and disabilities needed to be eliminated in their children. In this thesis, I argue that the Children's Bureau was ultimately far more effective by appealing to a wider audience, creating a plan for long-term medical care, and improving access to prenatal and postnatal care for women.

Social engagement has been clearly associated with socio-developmental outcomes in clinical and at-risk populations of infants, who show deficits in gaze following, face processing, and joint attention. Importantly, these are all skills related to language learning. This is most prominently illustrated by individuals with autism, for whom social engagement and language are markedly dysfunctional. In contrast, for typically developing infants the parameters of social engagement and language learning have only been generally defined. The present study was designed to relate infants' social attention to later language outcomes. In this longitudinal study, 11-month-old infants participated in social attention tasks (distracter, gaze following and face scanning tasks); at 14 months, infants returned to participate in language (word/object association) and joint attention (Early Social Communication Scales) tasks; at 18-20 months, caregivers reported on language (vocabulary size) and autistic symptomatology (developmental screening measures). Overall, the results indicated that measures of social attention predict later language outcomes. In particular, joint attention accounted for 13% of the variance in infants' word/object association performance at 14-months. More frequent response to the joint attention bids of an adult female tester (e.g., looking in the direction of her pointing) was associated with better word/object association learning. With regard to vocabulary size, two tasks emerged as significant predictors, the distracter and joint attention tasks, which together accounted for 38% of the variance in language at 18-months. Specifically, longer latencies (i.e., less distractibility) to look away from the face when an adult female was speaking (distracter task) and more frequently responding to the attention bids of the tester were associated with a larger productive vocabulary size. / Ph. D.

The purpose of the present study was to tease apart the paralinguistic from the linguistic aspects of infants' perception of infant-directed (ID) speech. Several studies have shown that infants beginning at a few days after birth discriminate native from nonnative speech and can discriminate specific contours (rising, falling, rising-falling) in ID speech. Some studies have also indicated that infants at 4.5 months of age prefer their own name over other names but at 6 months of age, fail to prefer a sentence with their own name embedded in it. Using a discrimination procedure, the current study investigated whether 6-month-old infants could detect a change in contour and/or a change in words when listening to ID utterances. Results indicated that 6-month-old infants detected both a contour and a word change. From these results, it is argued that as has been shown in other experiments, infants are extremely sensitive to subtle changes in speech. Furthermore, ID speech appears to facilitate infants' ability to discriminate small changes in ID speech (both linguistic and paralinguistic). It is suggested that future studies investigate more discrete changes in speech samples and a replication of this research with adult-directed (AD) speech. / Master of Science

Craniosynostosis is a disorder characterized by the premature fusion of one or more cranial sutures in the infant skull, resulting in an abnormal shape of the cranium. An effective surgical procedure for treatment of this disorder has been developed and is currently use called "Dynamic Spring Mediated Craniofacial Reshaping." This technique involves surgical removal of the fused suture and insertion of springs to expand the gap created by the suture removal in order to gradually reshape the skull to a more desirable shape. There were three primary objectives of this research: develop a device that could fabricate type 316 stainless steel wireform springs having consistent mechanical characteristics, evaluate the performance of the device, and develop a mathematical model to predict the mechanical characteristics of the fabricated springs. Use of the mathematical model facilitates further research to be performed that could determine the most effective use of the "Dynamic Spring Mediated Craniofacial Reshaping" surgical procedure. / Master of Science

The purpose of this research project was to examine the linguistic and prosodic content of infant-directed speech to infants, and to explore the relationship that exists between the prosodic features and the content of this speech, and how this relationship changes over the first eight months after birth. Analyses were conducted on maternal infant-directed speech directed to infants across three age groups: 1, 4, and 8-month olds. Speech samples were taken from 75 mothers (n = 25 per group) and both coded for content and analyzed for pitch (Fo) characteristics. Linguistic analysis indicated overall significantly more Informational speech that either Affective or Contentless speech directed to infants in all three age groups. In addition, significant differences were found within and between Affective and Contentless speech, but these effects were also mediated by age. Significant differences were also found in the acoustic features of maternal infant-directed speech, mediated by both type of speech and age. Overall, these results suggest that maternal infant-directed speech varies in both linguistic content and prosodic features, and that the variation of these prosodic features is mediated by both the type of speech used and the age of the infant. / Master of Science

Preterm infants are born after 20 weeks' gestation but before the completion of 3-7 weeks' gestation. Because of cardiopulmonary, gastrointestinal, and neuromuscular immaturity, preterm infants are at high risk for respiratory complications during bottle feedings. The purpose of this integrated review of literature was to compile evidence based nursing interventions to decrease respiratory distress during bottle feedings. Research findings were obtained through searches conducted in the CINAHL, Health Source, and MEDLINE databases. Results indicated that assessment of feeding readiness prior to the initiation of bottle-feeding was either lacking or inconsistent among neonatal units. Many hospitals lack protocols, failing to provide specific guidelines for the initiation of bottle-feeding with preterm infants. Feeding techniques such as external pacing, how the bottle was held, and oral support were statistically significant in positively influencing successful bottle-feeding. Because feeding criteria is limited and inconsistent, the risk of overlooking factors necessary for clinical decision-making to prevent respiratory distress is increased. Further research addressing the management of preterm infants during bottle feedings is needed to clarify which interventions are the most effective in preventing respiratory distress while promoting adequate nutritional intake.

M.Cur. / Please refer to full text to view abstract