From the article:
Mice on these three diets were given a neurotoxin called kainate, which damages nerve cells in a brain region called the hippocampus that is critical for learning and memory. (In humans, nerve cells in the hippocampus are destroyed by Alzheimer’s disease). Dr. Mattson’s team found that nerve cells of the meal-skipping mice were more resistant to neurotoxin injury or death than nerve cells of the mice on either of the other diets.
[…]
Previous studies by Dr. Mattson and his colleagues suggested that nerve cells in the brains of rodents on a meal-skipping diet are more resistant to dysfunction and death in experimental models of stroke and other neurological disorders including Parkinson’s, Alzheimer’s and Huntington’s diseases. Dr. Mattson also has found that meal-skipping diets can stimulate brain cells in mice to produce a protein called brain-derived neurotrophic factor (BDNF) that promotes the survival and growth of nerve cells.