# Some speculation on the possible detailed linkage of brain structure to cognitive function

I recall seeing, probably first on Steve Hsu’s blog, that brain structure is highly heritable, as high as g is, surprise surprise. In fact, g, currently measured non-physically through cognitive tests, is, to my intuition, unguided by detailed relevant knowledge of the area, in its scientific essence a function of brain structure that could be computed through data obtained from a direct neurobiological measurement (through MRI and what not).

On this, I have hypothesized a future where we will be able to predict with reasonable accuracy, to a fine grain of detail, behavioral traits as complex as one’s personality or one’s cognitive strengths and weaknesses (like what subjects one will find more intuitive), which have a high heritable component, and not only that, the course of their development across age. A clone of me who lived in that world could be told at age $n$ or so you will become like X, feel subjectively like Y, be at $X \pm \sigma$ across age group at Z, etc, at age $n+k, k > 0, k \in \mathbb{N}$. Of course, if say $n = 6$, I would only respond with a sense of awe and incredulity, but across time, I would attain ever deeper and more realistic understanding of what was going on, as can be said for virtually every subject matter for virtually every human that has ever lived on this planet. Perhaps this is pushing it a bit too far. Learning to this degree of precision may be too much; there would not be enough data, even if we sequence every human on the planet and run on a computer cluster orders of magnitude larger and more powerful than, say, Google’s jobs which continuously improve the models. However, I do believe we will get somewhere. We will reach the point where we can deliver with reasonable level of confidence personalized medicine and education and such for every individual in a way that based on rigorous biostatistical data as opposed to on blind human intuition, which of course still works well, most of the time, as is done now. What other comes to mind is, as you can probably guess, the possibility of evolving a population vastly different from our own, perhaps one with ability far beyond that of homo sapiens (say, a population wherein everyone is smarter than John von Neumann (which I highly doubt, as that would be rather non conducive to the well functioning of the world)). As for that, as for what should be done, I have little to say other than that we’ll have to decide for ourselves. I do think it would be not a bad thing to use this newly found knowledge to eliminate severe dysfunction and suffering on this planet, which could be done through the likes of preventing the birth of, say, those prone towards severe depression or towards becoming serial killers.

We’ll have to see what happens. Maybe I will be able to see something exciting, possibly even to the level just described, in my lifetime. I am still young, after all.