Health

1. Shake a leg. Lack of blood flow is a common reason for lack of concentration. If you've been sitting in one place for awhile, bounce one of your legs for a minute or two. It gets your blood flowing and sharpens both concentration and recall.
2. Food for thought: Eat breakfast. A lot of people skip breakfast, but creativity is often optimal in the early morning and it helps to have some protein in you to feed your brain. A lack of protein can actually cause headaches.
3. Food for thought: Eat a light lunch. Heavy lunches have a tendency to make people drowsy. While you could turn this to your advantage by taking a "thinking nap" most people haven't learned how.
4. Cognitive enhancers: Ginkgo biloba. Ginkgo biloba is a natural supplement that has been used in China and other countries for centuries and has been reputed to reverse memory loss in rats. It's also suggested by some health practitioners as a nootrope and thus a memory enhancer.
5. Reduce stress + depresssion. Stress and depression may reduce the ability to recall information and thus inhibit learning. Sometimes, all you need to reduce depression is more white light and fewer refined foods.