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Sexual aggression can disrupt processes related to learning as females emerge from puberty into young adulthood. To model these experiences in laboratory studies, we developed SCAR, which stands for Sexual Conspecific Aggressive Response. During puberty, a rodent female is paired daily for 30-min with a sexually-experienced adult male. During the SCAR experience, the male tracks the anogenital region of the female as she escapes from pins. Concentrations of the stress hormone corticosterone were significantly elevated during and after the experience. Moreover, females that were exposed to the adult male throughout puberty did not perform well during training with an associative learning task nor did they learn well to express maternal behaviors during maternal sensitization. Most females that were exposed to the adult male did not learn to care for offspring over the course of 17 days. Finally, females that did not express maternal behaviors retained fewer newly-generated cells in their hippocampus whereas those that did express maternal behaviors retained more cells, most of which would differentiate into neurons within weeks. Together these data support SCAR as a useful laboratory model for studying the potential consequences of sexual aggression and trauma for the female brain during puberty and young adulthood.

The adolescent hippocampus produces thousands more new neurons daily than the adult, yet many die within weeks of their generation ( Cameron and McCay, 2001; Curlik, DiFeo & Shors, 2014; Shors et al., 2016 ). Learning new skills can increase their survival. The present study tested the effects of physical skill training on the survival of these newly generated cells in males and female rodents during puberty. Newly generated cells were labeled with BrdU, a marker of cell mitosis, and training began one week later, just as the new cells begin to die. Significantly more BrdU-labeled cells were present in the hippocampus of both sexes after engaging in the physical training experiences. The young animals were able to maintain their balance on a modified rotarod task throughout most trials of training and as a consequence expended considerable energy and endurance during each training trial. These data suggest that a combination of both exercise and skill training can increase brain plasticity through increases in neurogenesis in the adolescent hippocampus. This finding supports the premise behind a clinical intervention known as MAP Training, which combines mental and physical training to enhance brain health in humans ( Shors et al., 2014 ; Alderman et al., 2016 ). Although theoretical at this stage, the positive consequences of MAP Training for brain function may be mediated through neurogenesis. This article is part of a Special Issue entitled SI: Adolescent plasticity . [ABSTRACT FROM AUTHOR]