Throughout the multitude of life experiences there exist moments of particular vulnerability, or «thresholds», where personal resources of the individual are tested and give birth to vastly different trajectories of aging. In light of the concepts of «threshold» and «vulnerability», the authors demonstrate that one can begin to discriminate in such circumstances the differences between normal and pathological components of aging. As such an approach does not directly concern common themes of memory, cognitive function, depression or loss, it represents a starkly different perspective from standard clinical studies.