I remember when cops would burn marijuana plants in the 70's.
Marijuana was categorized as an illegal scourge and you were going to lose your mind if you smoked it. Now my colleagues out west are prescribing medical marijuana for pain management, glaucoma, chronic disease, cancer and to save your brain from Alzheimer's.
If you live long enough you see everything.
Researchers have found a novel new treatment for Alzheimer's. Marijuana contains delta-9-tetrahydrocannabinol or THC and low levels may inhibit amyloid beta plaque formation associated with Alzheimer's. In vitro cell cultures, researchers found that THC did in fact inhibit amyloid beta production at low doses and it enhanced mitochrondrial function. Mitochondrial function makes ATP your energy source, it transmits signals and maintains a healthy brain.
Can you imagine assisted-living community parties now with low dose THC laced brownies at the dance parties? They also tested THC together with caffeine to see if there was any synergy. The combination did not have an additive affect. Coffee is great for your brain and your liver so I would serve coffee and THC brownies together.
How does Marijuana affect your brain and brain function?
In young people and frequent marijuana users there is concern about memory impairment as shown in the literature. Young people might be at higher risk for stroke when using pot, but that may be due to methylation defects, gender, individual bio-chemistry, pesticides and additives on the pot product or method of adminstration. This study found that memory impairment is only observed at "abuse" concentrations of THC. That level is more than a thousand times higher than the low doses used in the in vitro experiments.
Early-onset familial Alzheimer's and late-onset sporadic Alzheimer's have extracellular AB peptides and amyloid plaques with neurofibrillary tangles. How great if we have a natural plant substance that can prevent the progression. It is agreed that we need more studies and we need to study dosage and methods of administration. There may be a great role for cannabinoid therapy to stop a progressive neurodegenerative disease like Alzheimer's. 
