Figure 1.

Schematic of methodology and experimental timeline. In infancy, pups received either Scarcity-Adversity Model of Low Bedding (LB) rearing or control rearing from the mother (ages PN8–12). LB rearing involved providing the mother with insufficient bedding for nest building, which produces maltreatment of pups but growth indistinguishable from controls. Pups are odor-shock conditioned in the mother’s presence or absence at one of two ages, with the goal of better understanding the neural mechanisms involved in social suppression of threat. A portion of the pups had the brain removed immediately after conditioning, while the other half were tested the next day (Cue test involving odor only presentations). The younger subjects were PN18, an age when pups are still with the mother but only for about 5 days before weaning. The other age tested was PN28, when pups have been independent for about 5 days.