The New York Times recently published an article about the "brain fitness" business, "Do Brain Workouts Work? Science Isn’t Sure." I believe the answer is no. Without a variety of other daily habits, these "brain-training" games cannot stave off mental decline or dramatically improve cognitive function.

Most of these brain-training games will have some benefits, but it's impossible to optimize brain connectivity and maximize neurogenesis (growth of new neurons) sitting in a chair while playing a video game on a two-dimensional screen.

In order to give your brain a full workout, you need to engage both hemispheres of the cerebrum, and of the cerebellum. You can only do this by practicing, exploring, and learning new things in the three-dimensions of the real world, not while being sedentary in front of a flat screen. These digital programs can't really exercise the cerebellum (Latin: "Little Brain") and, therefore, literally only train half your brain. These "brain-training workouts" are the equivalent of only ever doing upper-body workouts, without ever working out your lower body.

Although the cerebellum constitutes only 10 percent of the brain by volume, it houses over 50 percent of the brain's total neurons. Neuroscientists are perplexed by this disproportionate ratio of neurons. Whatever the cerebellum is doing to optimize brain function and improve , it recruits a lot of neurons to do it.

Brain-Training Games Increase Sedentary

In the Times article, Tara Parker-Pope wrote, “While there is no real risk to participating in the many unproven brain-training games available online and through smartphones, experts say, consumers should know that the scientific jury is still out on whether they are really boosting brain health or just paying hundreds of dollars to get better at a game.”

I slightly disagree. I believe these programs do have a risk because they add more sedentary screen time to a person's day. This additional time spent on a mobile device or computer takes away from time that people could spend breaking a sweat, exploring the world, interacting with friends and family, making art, playing a musical instrument, writing, reading a novel, daydreaming, practicing , etc.

I did a meta-analysis of recent studies to compile a list of habits that can improve cognitive function for people in every generation. These habits can improve cognitive function and protect against cognitive decline for a lifespan.

1. Physical Activity

Last December, researchers at Boston University School of Medicine discovered more evidence that physical activity is beneficial for brain health and cognition. The study found that certain , which are increased during exercise, may help improve . The researchers were able to correlate blood hormone levels from aerobic fitness and identify positive effects on memory function linked to exercise.

In 2013, researchers at Dana-Farber and Harvard Medical School released a study showing a specific molecule released during endurance exercise that improves cognition and protects the brain against degeneration. (See "Scientists Discover Why Exercise Makes You Smarter.")

In their breakthrough discovery, scientists honed in on a specific molecule called irisin that is produced in the brain during endurance exercise through a chain reaction. Irisin is believed to have neuroprotective effects. Researchers were also able to artificially increase the levels of irisin in the blood which activated involved in learning and memory.

A 2013 study of children in Finland investigated the link between cardiovascular fitness, motor skills, and academic test scores. The researchers found that first-graders with poor motor skills also had poorer reading and arithmetic test scores. Across the board, children with better performance in fitness and motor skills had higher cognitive function and scored better in reading and arithmetic tests.

2.

A 2013 study, "The Impact of Sustained Engagement on Cognitive Function in Older Adults: The Synapse Project," found that learning new and demanding skills while maintaining an engaged are key to staying sharp as we age.

The findings reveal that less-demanding activities, such as listening to classical music or simply completing word puzzles, probably don't provide noticeable benefits to an aging mind and brain. Older adults have long been encouraged to stay active and to flex their memory and learning like any muscle that you have to "use or lose." However, this new research indicates that not all mind-engaging activities improve cognitive function.

Lead researcher Denise Park of the University of Texas at Dallas says, “It seems it is not enough just to get out and do something—it is important to get out and do something that is unfamiliar and mentally challenging, and that provides broad stimulation mentally and socially. When you are inside your comfort zone you may be outside of the enhancement zone."

Another study, from 2012, found that a training program designed to boost cognition in older adults also increased their openness to new experiences, demonstrating for the first time that a non-drug intervention in older adults can change a trait once thought to be fixed throughout a person's lifespan.

3. Curiosity and Creativity

A 2013 study from Michigan State found that participation in arts and crafts leads to , patents, and increases the odds of starting a business as an adult. The researchers found that people who own businesses or patents received up to eight times more exposure to the arts as children than the general public.

“The most interesting finding was the importance of sustained participation in those activities,” said Rex LaMore, director of MSU’s Center for Community and Economic Development. “If you started as a young child and continued in your adult years, you’re more likely to be an inventor as measured by the number of patents generated, businesses formed, or articles published. And that was something we were surprised to discover.”

Last year, neuroscientists discovered multiple ways that musical training improves the function and connectivity of different brain regions and improves cognitive function. Practicing a musical instrument increases brain volume and strengthens communication between brain areas.

Playing an instrument changes how the brain interprets and integrates a wide range of sensory information, especially for those who start before age seven. The findings were presented at the Neuroscience 2013 conference in San Diego.

In a press briefing Gottfried Schlaug of Harvard Medical School summarized the new research from three different presentations at the conference. He said, "These insights suggest potential new roles for musical training including fostering plasticity in the brain; have strong implications for using musical training as a tool in ; and for treating a range of ."

Another 2013 study found that reading books, writing, and participating in brain-stimulating activities at any age may preserve memory. Neuroscientists discovered that reading a novel can improve brain function on a variety of levels. This study of the brain benefits of reading fiction was conducted at Emory University and published in the journal Brain Connectivity.

The researchers found that becoming engrossed in a novel enhances connectivity in the brain and improves brain function. Interestingly, reading fiction was found to improve the reader's ability to put themselves in another person’s shoes and flex the imagination in a way that is similar to the an would do while mentally rehearsing a motion.

"Our study suggests that exercising your brain by taking part in activities such as these across a person's lifetime, from childhood through old age, is important for brain health in old age," concluded co-author Robert S. Wilson.

4. Social Connections

In 2014, John Cacioppo of the University of Chicago presented findings which identified that the health consequences of feeling can trigger psychological and cognitive decline.

Cacioppo's research found that feeling isolated from others can disrupt sleep, elevate blood pressure, increase morning rises in the hormone cortisol, alter gene expression in immune cells, increase , and lower overall subjective well-being. All of these factors conspire to disrupt optimal brain function and connectivity, and reduce cognitive function.

5. Meditation

A 2013 pilot study by researchers at Harvard's Beth Israel Deaconess Medical Center identifed that the brain changes associated with meditation and subsequent stress reduction may play an important role in slowing the progression of age-related cognitive disorders like and other dementias.

First author Rebecca Erwin Wells explained, "We were particularly interested in looking at the (DMN)—the brain system that is engaged when people remember past events or envision the future, for example—and the hippocampus—the part of the brain responsible for emotions, learning and memory—because the hippocampus is known to atrophy as people progress toward and Alzheimer's disease. We also know that as people age, there's a high correlation between perceived stress and Alzheimer's disease, so we wanted to know if stress reduction through meditation might improve cognitive reserve."

6. Brain-Training Games

Scientists are beginning to better understand the specific mechanisms of how patterns of electrical pulses (called “spikes”) trigger a cascade of changes in neural circuits linked to learning and memory. In a 2013 report, Tel Aviv University researchers found that " -rich" environments and problem-solving puzzles could be contributing factors in preventing or delaying the onset of Alzheimer’s disease in some people.

Researchers at the University of California, San Francisco (UCSF) have created a specialized video game that may help older people boost mental skills like handling multiple tasks at once. Adam Gazzaley of UCSF and colleagues published their findings in Nature in 2013.

In 2014, Johns Hopkins University researchers reported that as few as 10 sessions of cognitive training improved an older person’s reasoning ability and speed-of-processing for up to a decade after the intervention. If someone received additional "booster" sessions over the next three years, the improvements were even more dramatic.

7. Get Enough Sleep

Scientists have known for decades that the brain requires sleep to consolidate learning and memory. At the annual meeting of the Society for Neuroscience in San Diego in 2013, sleep researchers from Brown University presented groundbreaking new research that helps explain the specifics of how the brain masters a new task.

“It's an intensive activity for the brain to consolidate learning and so the brain may benefit from sleep perhaps because more energy is available, or because distractions and new inputs are fewer,” said study corresponding author Yuka Sasaki, a research associate professor in Brown University’s Department of Cognitive, Linguistic, and Psychological Sciences.

"Sleep is not just a waste of time," Yuka Sasaki concludes. The extent of reorganization that the brain accomplishes during sleep is suggested by the distinct roles the two brainwave oscillations appear to play. The authors conclude “that the delta oscillations appeared to govern the changes in the SMA's connectivity with other areas of the cortex, while the fast-sigma oscillations appeared to pertain to changes within the SMA itself.”

A 2014 study from University of California, San Francisco (UCSF) found an association between poor sleep quality and reduced gray matter volume in the brain's frontal lobe, which helps control important processes such as working memory and .

"Previous imaging studies have suggested that sleep disturbances may be associated with structural brain changes in certain regions of the frontal lobe," said lead author Linda Chao. "The surprising thing about this study is that it suggests poor sleep quality is associated with reduced gray matter volume throughout the entire frontal lobe and also globally in the brain."

8. Reduce Chronic Stress

Neuroscientists have discovered that chronic stress and high levels of cortisol can damage the brain. A wide range of recent studies have affirmed the importance of maintaining healthy brain structure and connectivity by reducing chronic stress, which lowers cortisol.

Neuroscientists at the University of California, Berkeley, found that chronic stress triggers long-term changes in brain structure and function which can lead to cognitive decline. Their findings might explain why young people exposed to chronic stress early in life are prone to mental problems such as and mood disorders later in life, as well as learning difficulties.

The "stress hormone" cortisol is believed to create a domino effect that hard-wires pathways between the hippocampus and amygdala in a way that might create a vicious cycle by creating a brain that becomes predisposed to be in a constant state of fight-or-flight.

The researchers found that hardening wires, may be at the heart of the hyper-connected circuits associated with prolonged stress. This results in an excess of myelin—and too much white matter—in some areas of the brain. Ideally, the brain likes to trim the fat of excess wiring through neural pruning in order to maintain efficiency and streamlined communication within the brain.

Chronic stress has the ability to flip a switch in stem cells that turns them into a type of cell that inhibits connections to the prefrontal cortex, which would improve learning and memory, but lays down durable scaffolding linked to anxiety, depression, and . (Yoga has been proven to lower cortisol levels and reduce chronic stress. See "Yoga Has Potent Health Benefits.")

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