Fetal programming and fetal psychology

Abstract

The introduction of the "fetal programming hypothesis," first in epidemiology, subsequently in a broad range of disciplines concerned with developmental biology, has generated new interest in phenotypic plasticity, the mechanisms that govern it, and its place in evolutionary biology. A number of epidemiological studies link small size at birth, assumed to be a consequence of constrained prenatal energy availability, with adverse effects on the risk of chronic diseases later in life. The cluster of chronic diseases associated with the metabolic syndrome and alterations of glucose metabolism are particularly implicated. Recent evidence suggests that epigenetic modification of gene expression affecting the hypothalamic-pituitary-adrenal (HPA) axis may be involved in these effects. In animal studies epigenetic alteration of HPA axis activity and responsiveness is associated with changes in adult behavior and stress responsiveness.The potential for similar effects to contribute to psychological and psychiatric outcomes has been explored in a number of contexts, including famine exposure, observed covariance with birth weight, and prenatal dexamethasone treatment of fetuses at risk of congenital adrenal hyperplasia. While fetal programming effects have now been widely demonstrated across species and human populations, the adaptive significance of these effects is still a matter of debate.Life is integrated, cumulative, and continuous, not episodic, static, or discrete.Behavioral scientists rarely forget this, but biologists often do. Developmental biology is the one domain of the life sciences where the organism as a progressively unfolding phenomenon is a central concept. The reemergence of developmental biology as a vigorous discipline, intersecting in important ways with genetics (Badayev, 2008), evolution (West-Eberhard, 2003), and epidemiology (Barker, 1994;Gluckman and Hanson, 2006;Kuh, Ben-Shlomo, Lynch, Hallqvist, and Power, 2003), has injected new energy and new ideas into all those fields. Within epidemiology a seminal impact of this new attention to developmental biology has been in the formulation of the "fetal programming hypothesis," also known as the "fetal origins hypothesis," or, more generally, as the "developmental origins of health and disease" (DOHaD). Simply put, this hypothesis suggests that conditions very early in development, even in utero, can leave lasting imprints of an organism's physiology, imprints that may affect susceptibility to diseases with onsets that may occur many decades later (Barker, Eriksson, Forsen, and Osmond, 2002;.The concept of fetal programming is, of course, not new. Behavioral endocrinologists and neuroscientists, for example, have long recognized "organizational effects" of prenatal androgen hormones in "programming" certain aspects of reproductive axis function and reproductive behavior that emerges later in an animal's life (Nelson, 2005). "Critical periods" in development, including fetal development, are familiar

Stress exposure in intrauterine life is associated with shorter telomere length in young adulthood

“…The developing fetus responds to, or is acted upon by, conditions in the internal or external environment during sensitive periods of cellular proliferation, differentiation, and maturation. These responses, in turn, may result in structural and/or functional changes in cells, tissues, and organ systems that have important long-term consequences for subsequent health and disease susceptibility (1)(2)(3)(4)(5). Exposure to psychosocial stress and/or biological stress mediators during gestation has been identified as one salient condition that may underlie the long-term programming effects of the intrauterine environment (2).…”

Epigenetic determinism in science and society

“…Research on plasticity is also associated with another form of deterministic language in the theory of fetal or developmental programming (e.g., Aiken and Ozanne 2014; Cottrell and Ozanne 2008; Ellison 2010). “Programming” in this context refers to the empirical observation that conditions, such as temperature or nutrition, experienced early in life do not only have immediate, but also long-term, effects on an individual's phenotype.…”

Building blocks of fetal cognition: emotion and language

“…In this context, the word plasticity deserves a new meaning: plasticity is not only observed in the adult brain as a response to an injury or to extreme training (e.g. music), but that in utero the fetal brain can be thought to have plastic capabilities to develop new optimal structures and functions according to the stimulation it receives during its development (see Ellison, 2009). The neonatal brain is a product of this development, not a tabula rasa but a constantly developing and already highly capable organ, which relies for its development not only on genetic or deterministic developmental continua but also on its history-the sounds, movements, smells, combinations of different sensations and their probabilistic patters.…”