Developmental cascades linking stress inoculation, arousal regulation, and resilience

Abstract

Stressful experiences that are challenging but not overwhelming appear to promote the development of arousal regulation and resilience. Variously described in studies of humans as inoculating, steeling, or toughening, the notion that coping with early life stress enhances arousal regulation and resilience is further supported by longitudinal studies of squirrel monkey development. Exposure to early life stress inoculation diminishes subsequent indications of anxiety, increases exploration of novel situations, and decreases stress-levels of cortisol compared to age-matched monkeys raised in undisturbed social groups. Stress inoculation also enhances prefrontal-dependent cognitive control of behavior and increases ventromedial prefrontal cortical volumes. Larger volumes do not reflect increased cortical thickness but instead represent surface area expansion of ventromedial prefrontal cortex. Expansion of ventromedial prefrontal cortex coincides with increased white matter myelination inferred from diffusion tensor magnetic resonance imaging. These findings suggest that early life stress inoculation triggers developmental cascades across multiple domains of adaptive functioning. Prefrontal myelination and cortical expansion induced by the process of coping with stress support broad and enduring trait-like transformations in cognitive, motivational, and emotional aspects of behavior. Implications for programs designed to promote resilience in humans are discussed.

Effects of maternal investment, temperament, and cognition on guide dog success

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Psychological Resilience in Older U.S. Veterans: Results From the National Health and Resilience in Veterans Study

“…These results suggest that although the Resilient group reported relatively low levels of current psychological distress, which were comparable to the Control group, they were more likely to have had periods of time in their lives when they would not have been considered psychologically resilient. It is possible that exposure to trauma and experiencing psychological difficulties earlier in life may have "stress inoculated" veterans to the deleterious effects of trauma, [15,[30][31][32]44] perhaps by enhancing coping skills and social support networks to be better able to cope with later traumatic life events. Prior mental health treatment might also partly account for the Resilient group experiencing low psychological distress in later life.…”

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