Researchers at Stanford University and MIT's Picower Institute for Learning and Memory had activated light-sensitive neurons in the brain's hippocampus involved in the memory of fright.
Oligomers, which are considered more toxic to brain tissue than amyloid-beta proteins, were applied to the hippocampus, the brain's memory center, in young mice.
These receptors are usually found in particularly high density in the cells of the hippocampus that are most vulnerable to the effects of Alzheimer's disease.
Another biomarker of interest is a protein called tau, implicated in the neurofibrillary tangles -- which basically take the shape of cells and destroy them -- that build up in the brains of Alzheimer's patients, particularly in the memory center called the hippocampus.