Amongst the brain focus supplements that are currently available in the nootropic drug market, Modafinil is probably the most common focus drug used by people, and it’s actually touted to be the best nootropic available today.  It is a powerful cognitive enhancer that is great for boosting your overall alertness with least side effects.  However, to get your hands on this drug, you require a prescription.
One curious thing that leaps out looking at the graphs is that the estimated underlying standard deviations differ: the nicotine days have a strikingly large standard deviation, indicating greater variability in scores - both higher and lower, since the means weren’t very different. The difference in standard deviations is just 6.6% below 0, so the difference almost reaches our usual frequentist levels of confidence too, which we can verify by testing:
For starters, it’s one of the highest antioxidant-rich foods known to man, including vitamin C and vitamin K and fiber. Because of their high levels of gallic acid, blueberries are especially good at protecting our brains from degeneration and stress. Get your daily dose of brain berries in an Omega Blueberry Smoothie, Pumpkin Blueberry Pancakes or in a Healthy Blueberry Cobbler.

There are many more steps to help support the optimal functioning of the brain and therefore encourage improved learning and development. However, another key strategy to support brain health is to increase intake of omega 3, an essential fatty acid, that is most abundantly found in oily fish such as salmon, mackerel and sardines. Be sure to choose salmon that has had less exposure to polluted water - visit the Seafood Watch web page to find the best sources. Omega 3 is vital for the brain’s function, particularly one of its components called DHA. This is a key building block for the brain and is what keeps neurons (brain cells) working well and supports proper signalling via neurotransmitters.
The use of prescription stimulants is especially prevalent among students.[9] Surveys suggest that 0.7–4.5% of German students have used cognitive enhancers in their lifetime.[10][11][12] Stimulants such as dimethylamylamine and methylphenidate are used on college campuses and by younger groups.[13] Based upon studies of self-reported illicit stimulant use, 5–35% of college students use diverted ADHD stimulants, which are primarily intended for performance enhancement rather than as recreational drugs.[14][15][16] Several factors positively and negatively influence an individual's willingness to use a drug for the purpose of enhancing cognitive performance. Among them are personal characteristics, drug characteristics, and characteristics of the social context.[10][11][17][18]