4 turning points when your brain changes: scientists already know when it’s coming

Although science and medicine know a lot about the brain and its functioning, it is still an organ that hides many secrets. However, modern research is producing new findings that point to turning points in its development. These key moments are said to occur at ages 9, 32, 66 and 83. What happens in the brain at these times?

Scientists at the University of Cambridge set out to analyse magnetic resonance images from just under four thousand people and came up with some surprising findings, which they published in the journal Nature Communications. The results suggested that the brain goes through five phases during life, during which four major turning points occur. During these phases, the brain undergoes visible changes that have a profound effect on memory, intelligence, personality traits and the ability to control emotions.

“These epochs provide important context for what our brains might be best at, or more vulnerable to, at different stages of our lives. It could help us understand why some brains develop differently at key stages of life, whether it’s learning difficulties in childhood or dementia later in life,” said Dr Alexa Mousley, one of the lead researchers.

Childhood

The first stage covers the childhood period from birth to age 9. This is an important period as it is during this time that the brain changes most intensely. There is a dizzying development of grey matter, which affects emotions and memory, and white matter, which is responsible for learning ability. At the same time, at an early age, the brain makes more neural connections than it needs and then reduces them. However, this process reduces the efficiency of the child’s brain, so the child processes information more slowly.

Adolescence

Then comes the phase that covers the period of adolescence from 9 to 30 years. The first turning point thus occurs at the threshold of childhood and adolescence. The brain is maturing and “rewiring” itself to function as efficiently as possible. In particular, neuronal connections are shortened, which speeds up the reception of information. During adolescence, skills such as decision-making and planning develop fundamentally. However, as psychologist Katie Insel of Northwestern University points out, between the ages of 18 and 21, while individuals are considered adults, their brains are still in a developmental process that doesn’t settle down until around age 32.

Adulthood

The next stage is adulthood, the turning point comes around the age of 32. This is the longest period of brain development, lasting about three decades. This phase is characterised by stability, as cognitive ability, intelligence and personality do not change significantly. However, as the researchers point out, the connections between the areas gradually weaken and do not function as efficiently.

“It’s not clear what exactly causes these changes, but they may be related to major lifestyle changes, such as starting a family or settling into a career,” Alexa Mousley told New Scientist magazine.

Premature ageing

The third tipping point occurs in early ageing around the age of 66. This stage can also be called premature ageing, but it does not come on suddenly. It is mainly due to the accelerated loss of nerve connections in the white matter.

“Data suggest that the gradual reorganisation of brain networks peaks in the mid-sixties. This is likely related to aging, with a further reduction in connectivity as white matter begins to degenerate,” Mousley continued. “This is an age when people face an increased risk of various health problems that can affect the brain.”

Late aging

The last key moment comes around age 83 during a period that is referred to as late aging. The connections between all areas of the brain weaken significantly, so the brain relies on using only certain parts. A major problem is the decline in neural connections, which makes communication between these areas more difficult. This increases the risk of dementia.

Lifelong development

Although brain development is generally associated with childhood, research shows that it is actually a lifelong process. The brain goes through successive phases that are influenced by the changing conditions in which people live.

“Understanding that structural changes in the brain are not a matter of steady development, but rather one of several major turning points, will help us identify when and how the brain’s connectivity is prone to disruption,” Professor Duncan Astle summarised the results of the study.