Influence of postpartum shock controllability on subsequent maternal behavior in rats

Abstract

Responses of mother rats were observed 24 h before and 24 and 72 h after exposure to one of three 8-day postpartum treatments: shock escape training, yoked inescapable shock, or restrained with no shock. In contrast to those in the other two groups, the dams given inescapable shock showed slower speed to approach the nest, shorter durations of being on the nest, and lower frequency and shorter total duration of oral contact with their pups. These dams also retrieved their pups less frequently, but this measure, as well as the frequency of leaving the nest, did not result in significant differences between groups. Since the traditional interpretations of the learned-helplessness effect were not entirely able to account for these findings, the observed uncontrollable-stress-produced changes in maternal behavior were examined from an ethological perspective.

Uncontrollable water deliveries and subsequent finickiness

“…The prolonged time course offinickiness in this experiment raises the possibility that the mechanisms underlying other helplessness effects that dissipate within 24-72 h (e.g., shuttle escape deficit) and finickiness may not be the same. However, a number ofother effects do not show dissipation in 24-72 h (e.g., suppresssion of exploratory behavior, see Bruto & Anisman, 1983; running wheel activity, see Maier, 1988, andMaier, Silbert, Woodmansee, &Desan, 1990; reduced aggression toward colony intruders, see Williams, 1982; altered maternal behavior, see Williams, 1984;analgesia, see Maier & Watkins, 1991). Possibly, the mechanism controlling finickiness is the mechanism underlying these longer lasting effects.…”

Influence of conspecific and predatory Stressors and their associated odors on defensive burying and freezing responses

“…Examining the relationships among fear, defense, and other responses has recently involved "ethoexperimental" analysis of behavior (e.g., Blanchard, Blanchard, & Hori, 1989;Blanchard & Blanchard, 1987;Williams, 1982Williams, , 1984Williams, , 1987Williams, , 1989Williams & Lierle, 1986). The major objective of this type of research is to observe the influence of motivational and contextual variables on a variety of species-typical behaviors in a serninatural laboratory environment.…”

Prior exposure to stress reduces the diversity of exploratory behavior of novel objects in the rat (Rattus norvegicus).

“…Relatively little experimental attention has been focused on the effects of stress on more naturalistic behaviors in less constrained experimental tests. One line of research that has focused on these issues is that from Williams's laboratory, which has investigated the effect of stress on aggressive and defensive behavior in a seminaturalistic environment (Williams, 1982(Williams, , 1984. A second line of research that is potentially relevant to these issues is that which has focused on the effects of stress on the animal's activity in or exploration of an open field (Anisman et al, 1978;Seligman & Beagley, 1975).…”