Fetal behavior in developmental psychobiology

Prenatal behavior has long held allure and mystery, to some extent due its relative inac-cessibility. Surgically implanted sensors, en-doscopy, and ultrasound-based imaging techniques have provided important glimpses of fetal movements and responses (Birnholz, 1988; Bradley & Mistretta, 1975; Smotherman & Robinson, 1986a). The most detailed and definitive data on prenatal behavior come, however , from studies of the mammalian fetus ex-ternalized from the mother's body with intact Developmental psycho-biology has been a particularly fertile area for the emergence and growth of research programs in fetal behavior. The increasing breadth and intensity of prenatal research may create, for some observers , a kind of disordered panoply of results. But we see coherence, not confusion. We recognize three broad themes among fetal behavior investigations. We shall define these themes (with references to specific studies, but without attempting an exhaustive review), and then consider their place in the field of developmental psychobiology and beyond. From this perspective there emerges a picture of progress and promise: Fetal behavior retains its role as antecedent raw material for the subsequent growth and differentiation of behavioral repertoire. At the same time, fetal behavior serves as a well from which we can draw for answers to basic questions of organization, function, and multileveled integration central to behavioral science. Assembly of behavior. Traditionally, be-havioral embryologists have been concerned with the origins and the subsequent steps by which behavior is formed or assembled. Are early movements autogenous and spontaneous in origin (e. The embryologists' classical formulations present wonderfully clear polarities. Perhaps this explains the impressive longevity of their questions. The answers, it turns out, are more varied and complicated than the questions. Not surprisingly, the forms of early behavior, like bodies themselves, differ across species (see, e.g., Provine, 1986). Legacies of the embryologists' original questions remain discernible amidst modern inquiries, which are aimed more at identifying specific characteristics of early behavioral change than at universal principles of operation , Investigators such as Bekoff and Lau (1980) maintain tradition when they employ frame-by-frame analysis to describe organizational dimensions of fetal rat behavior, such as Reprint requests should be sent to Dr.