Cell death or synaptic loss in Alzheimer disease

Abstract

It is an erroneous but common assumption that loss of neuronal perikarya causes the cognitive change in Alzheimer disease. Neither are senile plaques nor neurofibrillary tangles primarily to blame. In fact, it is the loss of synaptic contact that leads directly to the personal devastation. The death of neocortical synapses in the neuropil between plaques is probably the factor that activates the microglia.