Use it or lose it--do effortful mental activities protect against dementia?

The past 15 years, since the cloning of the gene for amyloid precursor protein, have witnessed breathtaking advances in our understanding of the pathophysiology of Alzheimer's disease, the most common cause of dementia. Most findings point to a final common pathway involving the accumulation in the brain of the toxic β-amyloid peptide, a degradation product of amyloid precursor protein, resulting in progressive neuronal damage and concomitant cognitive deterioration. Notably, the border between Alzheimer's disease and vascular dementia has become increasingly blurred as shared pathologic processes have been identified. Against this background comes the study by Verghese et al. in this . . .