Chronic corticosterone treatment impairs trace conditioning in rats with a neonatal medial prefrontal cortex lesion

Although there was considerable regeneration of much of the lesioned tissue in the medial PFC, a disruption of cortical layering and cortical thinning was observed in the adult brain. The chronic corticosterone treatment led to a decrease of corticosterone blood serum levels and reduced adrenal weights. Neither the neonatal lesion nor the corticosterone treatment alone affected trace conditioning; however, in rats that had received both treatments trace conditioning was impaired, suggesting synergistic effects between the lesion and the glucocorticoid treatment. An interaction between two adverse events that occur at different life stages complies with neurodevelopmental theories for some psychiatric diseases like schizophrenia.