Transcending Self Therapy Virtual Reality Expansion: Effect on Engagement, Completion and Temporal Usage Patterns.

Maternal effects, the influence of the mother's phenotype on the development of her offspring, can determine as much phenotypic variance within animal populations as do additive genetic effects (Moore et al., ). An important source of maternal effects is stressors experienced by mothers. Maternal stress effects may occur through several physiological pathways but have been best studied in the context of the glucocorticoid hormones/the hypothalamic–pituitary–adrenal (HPA) axis (Wingfield, ). In brief, when faced with an environmental challenge, activation of the HPA axis and the subsequent release of glucocorticoids is central to organisms' coping and responding appropriately (Wingfield, ). However, glucocorticoids in the developmental environment can also alter offspring phenotype and performance with potential implications for population and evolutionary dynamics (Eyck et al., ; Harris & Seckl, ; Sheriff, ). One way in which developmental stress effects have been suggested to contribute to population and evolutionary dynamics is through effects on social behaviour (Sheriff et al., ; Spencer, ). Elevated stress can be associated with (i.e. transiently expressed) effects on social behaviour in adults, such as grouping (Giesing et al., ; Muroy et al., ) and mate choice (Husak & Moore, ). Exposure to stressors during development can also have effects (i.e. permanent, determined during development) on the development of social phenotypes, resulting in persistent effects on social behaviours into adulthood. The majority of work to date suggests that exposure to stressors during development makes animals less social (Spencer, ). For example, early‐life stress reduces social bonding in prairie voles (: Perkeybile & Bales, ), maternal care in rats ( [Sprague Dawley]: Nephew et al., ) and social competence in cichlid fish (: Reyes‐Contreras et al., ). However, these effects are often context‐dependent. For example, zebra finches () exposed to elevated glucocorticoids during development exhibited reduced foraging associations with their parents in flocks but were more connected to flock members overall than control individuals (Boogert et al., ). While these effects have largely been studied in systems with established social structures (e.g. group/family‐living birds and mammals), exposure to elevated stress during development has also been shown to influence social behaviour in species that do not typically exhibit strong social structures. For example, in the common lizard (), exposure to prenatal stress promotes philopatry in offspring, increasing the level of association between parents and offspring (De Fraipont et al., ; Meylan et al., ). The impact of exposure to maternal stress can be mediated by other aspects of the environment experienced by the offspring (Rossiter, ). Positive social interactions can have significant mitigating influences on stress outcomes, a phenomenon termed ‘social buffering’ (Hennessy et al., ; Wu, ). For example, association with kin or conspecifics reduces stress effects in stickleback (: McGhee & Bell, ) and in wild macaques (: Young et al., ). Frequently, social buffering is studied in the context of direct forms of parental care (Gunnar et al., ). However, in many lizards, amphibians, fish and invertebrates, parental care is restricted to the tolerance of offspring remaining in natal ranges, with parents rarely interacting directly with their offspring (Rosenblatt & Snowdon, ). Whether social buffering plays a role in mediating the stress response when parent–offspring associations are relatively simple is unclear but could contribute to the context‐dependence of social grouping observed in these taxa.