Thank You, Robert Sapolsky
His brand of far-out seems to be simultaneously grounded in science and fueled by a radical dose of insane curiosity. In an article aptly titled “Dude, Where’s My Frontal Cortex?” for the blog Nautilus, Dr. Sapolsky describes a few of the more remarkable characteristics of adolescent brain development. He is not the first to identify these qualities – poor risk assessment, novelty seeking, and magnification of peer-relationships are well-documented characteristics among adolescents. Nor is he the first to elucidate the relationship between the characteristics and the relatively slow development of the prefrontal cortex – see Brainstorm, by Dan Siegel, for another well-researched treatment of this topic.
Dr. Sapolsky does, however make an interesting argument for the why of this delayed development, one that I’ve not read elsewhere. His argument is that the late bloom of the prefrontal cortex, and its attendant functions of impulse control, long-term planning, and emotional regulation (the so-called executive functions), allows for additional years of experience to wield a more significant influence in these neural networks, as opposed to being more largely genetically determined. Whereas an ancestor 100,000 years ago would require a cellular network for vision similar to our own, the unpredictable demands of environment require significantly more flexibility in the “higher” functions. What constitutes a risk, what a healthy relationship looks like, and the amount of novelty seeking required for individual success in a competitive gene pool are all posited as slippery variables, different from century to century and perhaps decade to decade. Thus, a pre-determined neural substrate informing these parameters would be a liability, through the evolutionary lens.
The delayed (if we can even call it that) development of our executive functions might simply be an appropriately timed incubation period during which the specifics of our particular environment have an opportunity to shape our nervous systems. This line of thought is particularly interesting to me in the context of the perceived expansion of adolescence, with physical changes beginning earlier and psychological changes ending later. I’m curious if the more complex modern environment, with its higher demand for information processing and abstract thought is just giving the nervous system more to chew on, requiring more adaption time.
In any case, perhaps rather than (or in addition to) viewing this expansion of adolescence across time as a burden to parents, educators, and society as a whole, we might consider that biology is actually giving us an opportunity – widening the window through which we can reach into our brains and craft our consciousness in the way that best reduces suffering and increases joy and peace.