Category: Articles

A comparative approach to the study of early experience and development is ubiquitous throughout the research initiatives of this network. Of particular relevance to the goals of this initiative are selective rearing studies with animals (rats and monkeys) that parallel the conditions under which young children are raised.

An example of such an undertaking can be found in recent pilot work conducted with Rhesus monkeys by Dr. Judy Cameron (a core group member). Dr. Cameron has separated monkeys from their mothers at four different ages: one week, one month, three months, and six months (this last age is when separation would occur normally). The behavioral repertoire of animals separated at three and six months is normal.

However, animals separated from their mothers at one month show profound behavioral (particularly emotional) deficits. For example, these animals quickly seek out an adult to adopt them, and latch onto this adult. Once adopted, …

Research focusing on the developmental outcome of children who experienced pre- or perinatal brain insult has demonstrated that children who are asymptomatic during the newborn period nevertheless often show cognitive deficits later in life. Behavioral measures of memory and cognitive ability during the infancy period have failed to consistently identify this subpopulation of at-risk infants. We designed two experiments that each reflect operations of the medial temporal robe and reflect pre-explicit memory. In the current protocol, electrophysiological techniques were used to examine the neural processing underlying recognition memory during the first year of life. Infants of diabetic mothers and infants suffering from growth retardation were tested on visual recognition memory paradigms at 6 and 8 months of age. Results suggest that fetal neurologic insults do result in abnormal patterns of electrophysiologic response to familiar and novel stimuli during the first year. (Also see Poster #G09; Neurophysiologic Assessment of Auditory Recognition …

Over the past decade, much information has been disseminated about “critical periods” – windows of plasticity, usually early in life, during which certain experiences must happen in order for certain abilities to develop. This concept has often been misapplied to suggest that only experiences early in life count, and that development and plasticity shut down after a certain point. This Network study has shown, however, that enriched experiences later in life can “re-open” windows of plasticity previously thought to be closed.

Earlier experiments have shown that young owls can effectively re-map their visual and auditory maps (including literally re-mapping the brain representations of these “maps”) when their visual input is manipulated by putting prisms over their eyes. These owls quickly learn the new relationships between auditory and visual input, and most adapt fully to the new relationship.

Adult owls, however, were largely unable to adapt to the shifted input. This …

As stated above, the ability to recognize faces and facial expressions of emotion are critical for the establishment and maintenance of proper social skills during the entire lifespan. This study seeks to examine the development of the neural bases of these abilties using ERP, or Event Related Potentials.

Electrophysiological Correlates Of The Recognition Of Objects, Faces, And Facial Expressions: An Erp Study

This study uses Event Related Potentials to study activity in certain areas of the brain suspected to play a role in recognizing faces and facial expressions.

ERPs represent electrical activity generated by the brain in response to a stimulus, such as a sound or image. Using a special cap (such as that worn by the baby in the image above our menu bar) with small electrodes that touch the scalp, researchers measure the electrical signals on the scalp generated by particular underlying areas of the brain.

This study …

For this project, Event Related Potentials are used to monitor brain activity in infant participants every two months from the ages of 4-months through 12-months. Two tests are done at each session. The first test consists of having infants watch pictures on a video monitor of their mother’s face and a stranger’s face. For the second test, infants watch pictures of their favorite toy (which has been brought in from home and digitally captured for presentation) and a novel toy. This project aims to understand the underlying processes of memory as they are used in detecting a familiar and a novel stimulus. Because this study is longitudinal we are also interested in how these processes may change with development.

At the 6 and 8-month sessions a short behavioral test is also done in which infants’ looking time to two different stimuli is recorded. The infants are first familiarized to a …

Development of a Computerized Orbito-Prefrontal Task – Certain tasks are known to “tap into” certain parts of the brain. This study examines the performance of children of different ages, and adults, on tasks known to rely on the orbito-prefrontal cortex (a part of the brain thought to play a role in emotion regulation and memory).

Certain tasks developed for animals have been shown to rely on a part of the brain called the orbitoprefrontal cortex. This study has adapted these tasks by computerizing them for use with children and adults.

One interesting finding in previous studies has been that there are distinct gender differences in the performance of these tasks during infancy and the first several years of life. These gender differences disappear, however, by the age of three or so, but re-appear during early adulthood. This would suggest that there are developmental differences in the orbitoprefrontal cortex between boys …

Social Modulation of Songbird Learning – The way that songbirds learn to sing may be a good model of the way humans learn language. One key feature of songbird learning is that it has a strong social component – that is, songbirds learn to sing much better by interacting with a live “tutor” than by listening to taped birdsong. This study examines the parts of the brain that are involved in this learning process.

SOCIAL MODULATION OF LEARNING IN THE SONG SYSTEM

A simple animal model for the acquisition of social behavior is the songbird, which learns to sing in much the same way that humans learn language. In particular, normal song learning is dependent both on hearing the songs of others during a critical period, and on social cues from adults. This study will examine how those social cues (or their absence) change both brain and behavior in adult …

Bucharest Early Intervention Project – This project examines the effects of intervention (in this case, foster care) on children who have been raised in orphanages.

EFFECTS OF EARLY EXPERIENCE ON BRAIN-BEHAVIORAL DEVELOPMENT

Several of our research projects examine the effects of early experiences on brain and behavioral development. Our most recent project in this vein is the Bucharest Early Intervention Project.

Many children raised in orphanages in Romania are at dramatically increased risk for a number of social and behavioral abnormalities such as disturbances of attachment, inattention/hyperactivity, externalizing behavior problems, and a syndrome that mimics autism.

This study compares children ranging in age from 3 to 30 months who are being raised in several orphanages in Bucharest, Romania, with one group of children of the same age removed from orphanages and placed into foster care, and another group of children of the same age who were raised in their home …

An enormous range of activities could fall under this heading. In this area we seek to focus on the role of experience in shaping physiology; physiology which in turn drives development and leads to behavioral outcomes. Our initial efforts focus on how early maternal (and possibly paternal) contact influences brain development and the consequent emotional development.

The importance of early socio-emotional relationships in facilitating healthy brain-behavioral development has recently been brought to our attention by what happens when otherwise normal, healthy infants are deprived of such relationships. For example, although children reared in institutionalized orphanages are deprived of a range of experiences (e.g., linguistic input; the opportunity to move and explore the environment), what most stands out in terms of their rearing is the profound deprivation from human contact; these children were not talked to, picked up, hugged, kissed, played with, and so forth. Not all such children suffer profound …

This study examined the interaction of early rearing environment and genetic background on the development of social behaviors in mice. Most research on the effects of early experience on development focuses on the timing and type of early perturbations. To date comparatively little research has focused on the role of genetic variation in how the nervous system interprets a particular type of experience. This study examines how genetic makeup might produce different responses, in adult mice, to early experiences. The study examined the response of several different strains of mice to varying periods of handling. Replicating earlier studies in rats, this experiment showed that animals handled daily for a relatively short period of time as infants show less response to stress as adults, compared to normal animals and animals handled daily for a very long period of time.

These experiments are the first step in laying the groundwork for significant …