Aging of the brain is inevitable to some degree, but the extent of the aging can vary greatly. In fact, everyone’s brain ages differently. And the ability to slow down brain aging or halting it altogether would no doubt be one of the most important discoveries in quest for eternal youth.
Is the aging of the brain just one of those things we have to accept? Or can we be proactive and take steps to reduce the speed of decline?
Throughout your time on earth, your brain undergoes more changes than any other part of your body. From the moment it begins developing in the womb to old age, it’s constantly changing as networks and pathways form and others disappear.
In the first few years of life alone, your brain forms more than a million new neural connections every second. In our preschool years the brain increases fourfold and by the time your six it’s almost 90% of the size it will be when you reach adulthood.
The frontal lobes, an area associated with higher functions like planning tasks, working memory and controlling your impulses is one of the last areas of the brain to mature and may not fully develop until you’re around 35.
Normal Brain Aging
The systems of your body naturally decline as we age, and that includes your brain. Lapses in memory or a “slipping of the memory” can be associated with getting older. However, some people can even experience those types of memory lapses as early as their 20’s but it’s often not too concerning.
However, when an older adult forgets something they tend to get slightly anxious or even alarmed. This is primarily due to their concerns over developing Alzheimer’s and dementia. Regardless, dementia and Alzheimer’s are not part of the normal brain aging process.
Here instead are some of the common issues associated with brain aging:
- Trouble learning new things: Memorizing things can take longer.
- Difficulty Multitasking: A reduction in processing time can make it difficult to carry on more than one task at a time.
- Problems recalling names and numbers: The strategy of memorizing names and numbers begins to decline as early as 20.
- Trouble remembering appointments: Without reminders and cues to remember information, appointments can be stored and forgotten unless the memory is jogged.
And while there are some studies that show that approximately 1/3 of older people struggle with what is known as declarative memory, which is the memory of facts or events that have been stored and can be retrieved, other studies show that as many as 1/5 of 70-year-olds perform just as well on cognitive tests as those in their 20’s.1
As I write this, researchers are currently in the process of putting together bits and pieces of multiple studies in an effort to put all of this together and to better understand how the brain changes over time.
Some generalized changes associated with brain aging include things like:
- Change in Brain Mass: Shrinking of both the frontal lobe and hippocampus - areas that are associated with higher cognitive function and encoding new memories – this starts around age 60 or 70.
- Change in Cortex density: A gradual thinning of the outer-ridged surface of the brain associated with a reduction in the total number of neuronal connections. Less connections could also mean slower cognitive processing.
- Changes in white matter: The white matter of your brain is made up of myelinated nerve fibers that are bundled together like telephone wires. They carry nerve signals between brains cells. As we age, it is assumed that the myelin begins to shrink and because of this there is an associated slowing of cognitive function.
- Neurotransmitters: Some studies show that as we age our brains generate less neurotransmitters, which are the chemicals associated with nerve transmissions. This decrease in dopamine, acetylcholine, serotonin and norepinephrine activity may be a causative factor in the decline of cognition and memory. It’s also potentially associated with depression.
By understanding the role nerve cells and their connections play in cognitive decline, researchers are more apt to discover new strategies that may help prevent or at the very least slow brain deterioration.
Recent Discoveries In Brain Aging
Studies on the aging brain are constantly going on and new discoveries are made almost daily.
In one recent study performed by researchers at Albert Einstein College of Medicine in New York found that stem cells in the brain's hypothalamus in mice is likely to control how fast aging occurs in the body.2
Dr. Dongsheng Cai, Ph.D., a professor of molecular pharmacology at Einstein says, "our research shows that the number of hypothalamic neural stem cells naturally declines over the life of the animal, and this decline accelerates aging,"
"But we also found that the effects of this loss are not irreversible. By replenishing these stem cells or the molecules they produce, it's possible to slow and even reverse various aspects of aging throughout the body."
What the researchers found is that when they Injected hypothalamic stem cells into the brains of normal elderly mice and middle-aged mice, whose stem cells had been destroyed, it slowed and even reversed aging. According to the researchers this is a huge first step toward slowing the aging process and potentially treating age-related diseases.
A rare group of individuals over the age of 80 whose memories are as sharp and healthy as people decades younger are referred to as “Super-Agers”.
The brains of these Super-Agers have been shown to shrink at a much slower rate than others the same age.
In one study, a research team from Northwestern University Feinberg School of Medicine in Chicago, IL, compared these Super-Agers with a control group made of people of similar age.
What they discovered is that the brains of the Super-Agers shrink at a much slower rate than their age-matched peers. This slower rate of shrinking is associated with a greater resistance to the typical memory loss observed with age.3
Emily Rogalski, an associate professor at the Cognitive Neurology and Alzheimer's Disease Center (CNADC) at Northwestern University Feinberg School of Medicine says, "we found that Super-Agers are resistant to the normal rate of decline that we see in average elderly, and they're managing to strike a balance between life span and health span, really living well and enjoying their later years of life.”
By continuing to study these Super-Agers and their unique brains, researchers are hoping to uncover biological factors that may contribute to a better understanding of how to maintain memory as we age.
Therapies To Help Slow Brain Aging
There are things that can accelerate brain aging. For example, being overweight in midlife can accelerate brain aging by as much as 10 years, and both regular and diet soda have been shown to increase the speed at which the brain ages. In fact, consumption of soda is associated with not only an increase in brain aging, but also lower brain volume, poor episodic memory and a shrunken hippocampus.4
And new research is beginning to show that people who experience the least amount of cognitive decline and memory as they age share some common characteristics:
- They get regular physical activity
- They partake in brain stimulating activities
- They remain socially active
- They manage stress effectively
- They tend to eat healthier
- They get plenty of sleep
In addition, new studies are beginning to uncover a variety of ways that we can actively take control and possibly decrease the rate at which our brain ages.
One of the most consistent interventions shown to stave off age related cognitive decline is exercise.
Moderate intensity aerobic and resistance exercise for at least 45 minutes each session and on as many days of the week as possible has been reported to boost brain health in people over the age of 50.
In addition, research performed at the University of Miami found that people over the age of 50 who performed little to no exercise suffered a decline in memory and thinking skills comparable to 10 years of aging in 5 years, when compared to those who engaged in a more vigorous exercise program.
In essence, physical activity slowed brain aging by 10 years.5
In a study performed by the German Center for Neurodegenerative Diseases in Magdeburg, Germany found that while regular exercise does reverse the signs of brain aging, the most profound effect was seen in people who danced.6
Playing an instrument
Researchers from Baycrest Health Sciences in Toronto, Canada, found that learning to play a musical instrument changes brain waves and improves an individual's listening and hearing skills. This alteration in brain activity appears to indicate that the brain can rewire itself to compensate for disease or injuries that may interfere with a person’s ability to perform daily tasks.7
Dr. Bernhard Ross, senior scientist at Baycrest's Rotman Research Institute, says "It has been hypothesized that the act of playing music requires many brain systems to work together, such as the hearing, motor and perception systems, this study was the first time we saw direct changes in the brain after one session, demonstrating that the action of creating music leads to a strong change in brain activity."
Another important factor for brain health is diet. Recent studies have linked omega-3 and omega-6 fatty acids in the blood with healthy brain aging.8
In a separate study, researchers found that consuming foods included in the Mediterranean or the MIND diet is associated with a lower risk of cognitive decline and memory issues in the elderly.9
University of Illinois, Researchers found that middle-aged people with higher levels of lutein - a nutrient that is found in green leafy vegetables, like kale and spinach, eggs and avocados - had similar neural responses to younger individuals than of people in their age group.10
Anne Walk, a postdoctoral scholar and the first author of the study had this to say, "as people get older, they experience typical decline. However, research has shown that this process can start earlier than expected. You can even start to see some differences in the 30s, we want to understand how diet impacts cognition throughout the lifespan. If lutein can protect against decline, we should encourage people to consume lutein-rich foods at a point in their lives when it has maximum benefit."
Over the next 40 years, the number of adults over the age of 65 is set to double. Going from 40.2 million in 2010 to an estimated 88.7 by 2050. Because of this spike in the aging population, finding ways to slow down age related cognitive decline and the deterioration of memory is a prime objective to researchers worldwide.
And while there are questions that remain unanswered, research on brain aging is expanding daily and progress is being made. You can preserve your mental abilities and improve your brain health, you just have to take the appropriate steps.