Interesting article. The key statement in this article from 1998 is this:

"Cannabidiol was more protective against glutamate neurotoxicity than either ascorbate or α-tocopherol, indicating it to be a potent antioxidant. These data also suggest that the naturally occurring, nonpsychotropic cannabinoid, cannabidiol, may be a potentially useful therapeutic agent for the treatment of oxidative neurological disorders such as cerebral ischemia."

The study was done in-vitro (test tube) with rat brains.

This study also supports the need for anti-oxidant supplements for their neuro-protective value. Progesterone and Metformin (a diabetes drug) are also being studied for their neuro-protective value.

More recent research suggests that the cannabidiol is neuroprotective as a result of its effect on the increase in Cerebral Blood Flow (CBF) This tends to negate some of the anticipated promise of cannabidiol as there are other ways to increase cerebral blood flow such as light exercise. The glutamate toxicity issue can be addressed through diet restrictions from MSG and processed soy products (free process glutamate).

The memory problems associated with THC are counter to the needs of the PCS subject.