What is the Progressively Lowered Stress Threshold (PLST) model and how could it be applied to reduce the emotional problems of persons with dementia?

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A useful theoretical framework in reducing emotional and psychological problems is the Progressively Lowered Stress Threshold (PLST) model, which was originally developed by Hall and Buckwalter (1987). Adapted from stress adaptation and coping models, the PLST model identifies clinical triggers such as fatigue, change in routine, inappropriate stimulation, and internal and external demands that exceed the capacities of the person with dementia.

Reference:
Buckwalter, K., & Hall, C. (1987). Families of the institutionalized older adult: A neglected resource. In T. Brubaker (Ed.), Aging, health, and family: Long-term care (pp. 176-196). Newbury Park, CA: Sage.