Various studies place the average age of cataract surgery patients at between 70 and 73. More Info: The incidence of cataracts among Americans is relatively high.
Serotonin. Serotonin is an inhibitory neurotransmitter involved in the regulation of mood, anxiety, libido, compulsivity, headaches, aggression, body temperature, eating disorders, social anxiety, phobias, sleep, appetite, memory and learning, cardiovascular function, muscle contraction, and endocrine regulation.
Glutamate is the most common neurotransmitter in the brain and is involved in learning and memory. As the brain cells of someone with Alzheimer's Disease die, they release excess amounts of glutamate.