Brain Development From Birth to Old Age: An Overview

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Comedian Lewis Black does a brilliant riff on the aging brain. The conversation he demonstrates between two adults trying to converse about a film looks something like, at best, a game of charades, or worse, infants trying to communicate wordlessly with each other — (the very etymology of the word “in fans” is “without speech”). One guy makes reference to the movie, trying to remember the name: “You know — the movie with the guy in it — the guy — you know the guy — the guy who knows the other guy, or looks like the other guy — the two guys — you know who I mean — that movie with the guy.” That’s not an exact quote, but close enough for anyone suffering from the affliction of getting older with a modicum of memory loss to get the point. (They tell us it’s part of the normal aging process. But who believes them?)

Most of us over 50 see our memories scarily fading away. We wonder: Are we relegated inevitably to blathering, blubbering about — returning to our pre-speech days?

Not necessarily. In fact, recent research into the brain leads to the conclusion — not at all.
Research into the brain is one of the fastest growing fields of study in contemporary science. What we know about the brain today is vastly different than what we thought we knew just 10 years ago. And 10 years from now, it is likely that most of what we think about the brain today will have been overturned, and replaced by new knowledge. One indication of the infancy of the field is the amount of attention that is given to studying the brain (and its accompanying nervous system) in medical schools. It accounts for a mere 20 percent; the remaining 80 percent is devoted to human anatomy, physiology and the systems of respiration, circulation and digestion. At least in medical school the brain seems relatively unimportant.

Thanks to new imaging techniques, we can now actually look inside a living brain. We know that when the brain is active, it demonstrates the attributes that we generally call intelligence. As well as having the capacity to learn, to recall, to express feelings and to conjure up thoughts and ideas, an active brain also dreams, argues beliefs, formulates discernment, makes decisions, creates behavior. We usually think about these qualities as belonging to the mind. But without the brain, the mind does not exist. The mind is, in essence, the brain in an animated state. For intelligence to grow, for emotional balance to be created, for understanding and experiencing the meaning of our individual lives — for all of what we value and cherish about what it means to be human, we need an animated brain.

You can do exercises — with all brains, all ages — that are fun and will grow your brain. I call the exercises Brainercize. My next blog will give some of these exercises.

The Newborn Brain

Screen Shot 2015-09-03 at 11.29.18 PMThe brain is equipped with the largest amount of neurons it will ever have in utero — between the third and sixth month of gestation. After birth, the infant will enter the time when all five senses are being used. Offer a baby a rattle, and she will first look at it, using her visual sense. Then she may grab onto it, using her tactile sense. Then she will shake it, using her auditory sense. She may try to smell it.

The Adolescent Brain

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Brain growth peaks in girls when they are 11, and in boys when they are 12-and-a-half: nerve-signal transmissions become faster and more efficient at these ages. Look at the brain functioning of adolescence is being like an efficient racing car: it has fewer connections, but operates faster. Part of the challenge of the adolescent brain is to balance the limited perception of long-term consequences with this powerful sense of urgency.

The Adult Brain

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Many higher cognitive skills, including judgment, emotional regulation and self-control, organization and planning, are not fully formed until adulthood. By the time we have reached our twenties, we have honed our sensory experiences. Taste, touch and smell have fallen into the background of the more ever-present auditory and visual senses.

The Mature Brain

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The brain keeps growing throughout adulthood, specifically in the temporal lobe and frontal lobe — the parts of the brain that largely differentiates us from animals. This continued brain growth into late middle-age and old age can be associated with better emotional development and wisdom and perspective. But research verifies that the changes in the mature brain are much more complex: it loses reaction time, short-term memory ability and processing speed.