In 1907 Alois Alzheimer's reported a case of a syndrome consisting of cognitive deterioration and behavioral disturbances in a middle-aged woman with an unusual neuropathologic picture , beginning the long road toward the understanding of Alzheimer's disease (AD). Since AD was first described, it become clear that symptoms develop gradually over many years.
A second landmark was Katzman's notion of brain reserve, proposed in 1988. This concept was based on the apparent capacity of brain to protect itself against dementia despite the presence of neurodegeneration , providing a potential explanation for the delay in clinical onset of dementia associated with many putative protective factors. It was supported by several subsequent studies ranging from brain volume size  to neuropathologic studies . These studies, demonstrating that substantial AD pathology may exist without producing clinical symptoms, led to important considerations regarding AD and other dementia preclinical stages, and to the characterization of certain mild impairments as high-risk conditions to develop dementia.
Was this article helpful?