The main aim of our research is to investigate how the environment interacts with individual characteristics in influencing behavioral and psychological development, as well as physical health. We try to answer questions about the ontogeny of behaviors (e.g., attachment) and internal states (e.g. cortisol levels), while keeping in mind their survival or adaptive value. We are especially interested in the period of early development.

One of the most important physiological systems underlying our behavior is the stress system. This system not only regulates our behavior when confronted with threatening situations (i.e., flight/fight responses), but it also regulates other bodily functions such as immune functioning, digestion, mood and emotions, and energy metabolism. A major line of research in our lab is the development and functioning of the Hypothalamic Pituitary Adrenal axis, one of the key physiological stress systems. We study how the HPA axis is related to (prenatal) stress, caregiving, feeding, sleeping, behavior, health and emotions. At the same time we study the development of the intestinal microbiota, the microbial community in our gut that begins to develop after birth, and that is related to our health, stress status, and even our behavior. Abnormal functioning in both the HPA axis and the gut microbiota are related to behavioral and cognitive anomalies, and may both be related to the development of stress-related disorders later in life, for example, depression, anxiety, obesity, and irritable bowel syndrome.

We focus on basic aspects of development in normal populations, trying to understand how caregiving decisions of parents, for example in the realm of sleeping arrangements, (breast)feeding, and non-parental caregiving, are related to how the child develops. Other topics within our basal research are the transition to parenthood, from hormonal, emotional and behavioral points of view, and the links between stress physiology and socio-emotional functioning in middle childhood. But we are also carrying out research of a more applied nature and in vulnerable populations. For example, we study prenatal stress in women of low SES, the effects of early life adversity on later cognition, the relations between stress and (emotional) eating, and how parental caregiving is related to development in preterm infants. Our research has been primarily longitudinal, with one major ongoing study, the Bibo study, following children and their families from pregnancy till the age of 11 years (see BIBO-STUDY).