The major cause of dementia is Alzheimer’s Disease, and this probably accounts for around 50% to 60% of cases of dementia worldwide. We know that Alzheimer’s Disease is characterised by specific pathological changes that occur inside the brain which were originally described by Dr Alois Alzheimer as we discussed in a previous topic. Scientists now believe that these pathological changes begin in middle age and accumulate slowly.
Changes include those that happen at the macroscopic level, which involves shrinkage or atrophy of the brain, and this can affect certain structures of the cerebral cortex, including the frontal lobe, temporal lobe and parietal lobe.
Pathological changes occur at the microscopic level, and these are neurofibrillary tangles and amyloid plaques.