3 Related ideas: Your health, Your genes, and your brain speed. Brain Speed might be better termed "neural conduction velocity."
If you body was a PC or hi-def tuner, the assessment might be called 'bandwidth.' It is a measure of how quickly your brain can process symbolic functions. It is no coincidence that brain speed is correlated with IQ. The kind of exercise that measures 'brain speed' - known as ECTs or elementary cognitive tasks, were viewed initially as another, possibly superior version of IQ test.
For example, early IQ tests and even the Stanford-Binet test had the well-known cultural limitations apparent in such constructs as the Scholastic Achievement Test (SAT) which favored white, upper middle class students with probably a suburban reference point. Depending on how close you were to this archteype, your were more likely to do well. Take your SAT test, designed for suburban kids in Princeton, New Jersey and give it to a teenage Dinka tribesman in the Sudan of similar age. Obviously the Dinka would barely be able to write his name on such a test and would not understand any of the associations and analogies. Even the quantitative reasoning section would be biased. Translating the test would not improve the outcome.
Now take an extremely simple measure without words or with a simple Yes/No option - such as how quickly you can push a button when a light comes on or a symbol flashes, and you have an instrument which can be used across cultures and even across species in some cases. The result is actionable information that can be used to correlate with human genetic types and variations, disease and health conditions, and create a personalized plan for optimization, which includes greater longevity and cognitive ability.
In other words, the process is now coming into place for us to step forward and make a major jump in evolution and perceptive ability, which is not necessarily the same thing as our ability to design and build devices or machines that 'simplify' our lives. Going back into human history, there was a time when humans were able to understand symbols as a form of communication and expression, despite having only elementary manipulative technology to alter their environment. To some extent, perception of symbolic meaning might be lessened or 'dampened' in direct proportion to our reliance on manipulative technologies (tools) that reduce our ability to visualize by filling our perceptive fields (sight, sound, olfactory, and more) with a distracting level of activity that serves no purpose other than justifying its own existence.
By improving human bandwidth or brainspeed with repetitive symbolic exercise we train ourselves to develop more flexible, effective, and enhanced cognitive abilities, a benchmark of health, longevity, and thinking into the future.