Environmental Enrichment and Early Life Pain: Effects on Stress and Nociception

Abstract

Early life pain is known to cause long-term alterations, including a global reduction in pain sensitivity and decreased anxiety behaviors. An enriched environmentcharacterized by increased social interaction, exploratory behavior, and physical activity- has been shown to have many beneficial effects including increased learning and memory, a reduction in anxiety behavior, and increased nociceptive responses. The purpose of this study was to determine whether the long-term negative consequences of early life pain could be buffered by living in an enriched environment. Male and female mice were placed into one of three early life conditions: a surgical procedure on post-natal day one, and sham surgical procedure, and control. Half of the animals were subsequently housed in an enriched environment upon weaning. In adulthood the animals underwent three pain tests and one test of stress response. Results from our study suggest that the enriched environment was able to reverse the long-term consequences of early life pain.