also can be called stochastic or non-genetic theories
caused by accumulation of insults from the environment
Environmental toxins include
ultra-violet, cross-linking agents (unsaturated fats), toxic chemicals (metal ions, Mg, Zn), radiation and viruses; and can result in errors in protein synthesis and in DNA synthesis/genetic sequences, cross-linkage of molecules, mutations.
Psychological Theories: Stess Theory
homeostatic imbalances result in changes in structural and chemical composition
General Adaptation Syndrome (Selye)
initial alarm reaction, progressing to stage of resistance, progressing to the stage of exhaustion; linked to hormonal theory
Erikson's bipolar theory of lifespan development: stages of later adulthood
Integrity: individual exhibits full unification of personality; life is viewed with satisfaction, optimisim, and growth. Despair: lack of ego integration; feelings of regret and disappointment and fear of death
life experiences/lifestyle influences aging process
older people that are socially active show improved adjustment to the aging process and role enactment is essential for a positive self image and satisfaction
older adult is distance from society; reduction in social roles leads to further isolation and life dissatisfaction
increasing reliance on others for meeting physical and emotion needs; focus is on self
Ingrated model of aging
aging is complex, multifactorial and not one single theory about aging can adequately explain it.