How the Brain Changes From Birth Through Old Age

How the Brain Changes from Birth through Old Age

Even though you’re born with only one brain, the brain health the one you have now is much different than the one you were born with. How much different? Think about this: even before you are born, fetal development leads to the production of 250,000 cells per minute and 1.8 million new neuronal connections per second. With all that potential brain power, we can only begin to imagine how things progress from there. Let’s look at the stages your brain goes through as you age. We’ll also discover tips on how to keep your brain as young as possible.


Before Birth

Even during the prenatal period, the human brain is highly active. By at least 22 weeks of gestation, there are even signs that your brain can learn. For example, a fetus will respond to repeated stimuli like noise and touch, but the response gets ignored after a while. This is a very basic kind of learning called habituation. There is also evidence that shows newborns can remember music and their mother’s voice that was heard earlier in the womb.

The best way to preserve the baby’s brain health is for the mother to be as healthy as possible. This means a nutritious diet, reasonable amount of exercise, stress reduction and avoidance of tobacco and alcohol. The final result of fetal brain development is a true miracle — 100 billion neurons and millions of support cells all in their right place in the brain’s multiple lobes and regions.

Infant Years

By the time you are born, the 100 billion neurons you have will stay about the same in number until you reach old age. At birth, your basic reflexes are present as well as the five senses of sight, touch, smell, hearing and taste. During these first few years, your neurons grow in size and efficiency. Stimuli and good nutrition help your senses become more fine-tuned, and this process happens rapidly. Also, your ability to learn, which started even before birth, advances at an incredible pace. By 2 years old, the human brain is about 80 percent of its adult size.

Childhood Years


At this stage of life when you are beginning to walk and talk, you already have strikingly well-developed cognitive skills. This means you can think, learn, understand and remember things. As childhood progresses, you begin to develop a personality and social skills, plus your motor skills improve every day. The best part of this stage of life is that your imagination soars.

Synapses are connections between neurons, and the child’s brain has twice as many synapses as an adult. The synapses used most often will be preserved, such as those used for language skills. Unused synapses will eventually die naturally. For this reason, childhood learning and stimulation are critical. It’s during your childhood that brain pathways get established for many years to come. Good nutrition and plenty of physical activity obviously help here. Healthy amounts of protein, especially eggs, fish and nuts, as well as oatmeal are excellent for growing minds. Even though it’s not easy, sugary foods should be avoided as much as possible.

Teenage Years

By the time you’ve reached your teen years, your brain has fully developed in size to weigh about 3 pounds. However, even though the brain is adult-sized, the inner wiring still has a way to go, which may explain the sometimes bewildering behavior of adolescents. Studies have shown that teens lose gray matter in the brain at a rate of 1 percent per year until around age 20. The reason this happens is that during growth spurts, these areas of the brain become overgrown. As the experience of the teen years moves forward, unused synapses get pruned away.

This cerebral pruning process favors basic sensory and motor skills first. Later, brain regions involved in language and spatial orientation get remodeled. The last ones to undergo change are areas involved in higher processing and executive functions. The very last area of the brain that matures is the dorsolateral prefrontal cortex. Not surprisingly, this area is involved in impulse control, judgment and decision-making.

Adult Years

By your mid-20s, you’ve reached your peak brain performance, and this optimal stage lasts about 10 years. Believe it or not, even by your mid-30s abilities like reasoning, spatial skills and speed of thought start to deteriorate. Episodic memory, which is how well you remember details about certain events, also suffers since the brain’s processing speed slows down and your working memory has less capacity for information storage.

Physically, your brain begins to go through these changes:

  • Overall volume loss
  • Thinning of cortex
  • Myelin sheath degradation, which slows down nerve signal speed
  • Brain receptors fire slower

By your mid-30s the decline in total neuron number begins to steepen. Actions like remembering names become more difficult. It also gets harder to learn new tasks. These difficulties continue into middle age and old age.

Middle Age

At this time of life, some startling changes begin to occur in brain function, but not all of them are bad. As far as thinking velocity goes, things continue to slow down. For instance, logical reasoning, memory and verbal fluency all get worse.

You can test your verbal fluency by counting how many words you can say related to a particular category in one minute. Try the test yourself by picking a letter in the alphabet and name as many words in 30 seconds as you can that start with that letter — use common letters such as B, N, T or S. A score of 10 to 15 indicates reasonable verbal fluency.

Still, not all the changes associated with middle age are negative. For instance, moral decision-making, emotional processing and interpreting social situations all improve dramatically in middle age. In general, at this time of life, you become wiser, which affords many benefits. It may be that a preservation instinct kicks in during these years, where earlier it was all about risk-taking and experimentation.

Your 60s


Through the years you’ve accumulated a ton of knowledge and experience. However, once you enter into your 60s, it gets a lot harder to access that information. Also, it’s more difficult to add to your memory. It’s very similar to an old computer whose processor and memory are beginning to get outdated.

Even though some of the changes at this stage of life are irreversible, you can slow down further deterioration. Besides plenty of exercise and a healthy diet, here are some more activities that may improve your cognitive ability:

  • Stress reduction: Chronic stress may elevate cortisol levels and increase the chances of developing dementia; don’t spread yourself too thin
  • Maintain social connections: An active social life appears to have protective effects on brain function; keep up with old friends and make new ones
  • Keep learning: Brain stimulation may help prevent or delay the onset of Alzheimer’s disease; take classes, learn a new language or practice mind exercise games like sudoku
  • Control your blood pressure: High blood pressure may increase your risk for certain types of cognitive problems; check your blood pressure at least once a year
  • Eat these foods: Blueberries, strawberries, raspberries, spinach, broccoli, cauliflower, salmon, mackerel, halibut and tuna; these foods are high in vitamins and antioxidants to keep your neurons healthy

Your 70s and 80s

At this stage of life, it’s nearly universal that people notice their brain function has slowed considerably. Still, this doesn’t mean that everyone at this age will suffer from dementia. About 10 percent of people age 65 and older have Alzheimer’s disease, but that also means 90 percent don’t have the illness. Still, everyone in their 70s and 80s has lost brain cells in areas like the hippocampus, which is where memories get processed. Surprisingly, even at an advanced age, the brain has a substantial level of resilience.

There appears to be one factor that makes the biggest difference: exercise. What can it do for your brain health?

For starters, some research shows that exercise may stimulate the growth of new brain cells. It might also stimulate new neuron synapse formation. Given that the general trend is a net neuronal loss through the years, any new cells are of high value. Exercise also helps stabilize your blood sugar, which maintains a healthy environment for all cells in your body, especially the areas of the brain associated with memory.

The Future Looks Bright

One of the best things that happens to your brain as you age might be selective memory. It turns out that, in general, you tend to forget bad experiences and remember good ones as you age. This might be the best built-in mechanism your brain has to help you age gracefully and experience more happiness with time.

A healthy body means a healthy mind. Take the right steps today to keep things working better for tomorrow.

For your comprehensive guide to increasing your brain health, check out the 14-Day Brain Health Quick Start Program, here!

14-Day Brain Health Quick Start Program