7 Cool Things You Might Not Know About Your Brain

1. Your Brain Prevents You from Acting Out Your Dreams

REM sleep stands for Rapid Eye Movement sleep. It's the phase of sleep when you're actively dreaming and is accompanied by eye movements. "It's as if the eyes are literally 'watching' the dream," says Dr. Clifford Saper, Chief of Neurology at Beth Israel Deaconess Medical Center. "During REM sleep, groups of nerve cells in the brain become active and bombard the nerve cells that control your muscles with signals that prevent you from actually acting out your dreams. So, during REM sleep your entire body, except for the muscles that control breathing, is paralyzed."

Dr. Saper studies REM sleep behavior disorder (RBD) in individuals whose brains do not send these signals to prevent them from acting out dreams. He hopes to find out what impact RBD may have on their brains later in life.

2. Your Brain Has about 100 Billion Neurons to Protect!

"To get an idea of how big this number is, imagine counting all 100 billion neurons at a rate of one per second. It would take you about 3,171 years," says Dr. Michael Alexander, a neurologist at BIDMC who specializes in traumatic brain injury (TBI). Each neuron may communicate with thousands of other neurons through connections called synapses.

"All of that activity is housed within the skull, which is made up of 22 bones that are fused together, and within the skull, the brain is suspended in cerebrospinal fluid that acts as a cushion to physical impact." If a jolt or blow to the body or head is strong enough that the cerebrospinal fluid is unable to provide sufficient protection, a concussion can occur.

"A concussion is a temporary change in the way the brain works caused by damage to the neurons," says Dr. Alexander. "While the brain is recovering, it's more sensitive to increased stress or injury, and that's why it's so important to allow the brain to fully heal before resuming activities after injury."

3. Your Brain is Constantly Changing

"We used to think about the brain as this very complicated complex organ, with fabulously complicated brain cells, connected in intricate ways, and that the brain took a long time to develop, but once developed, it did not change, and it was downhill from there," says Dr. Alvaro Pascual-Leone, Chief of Cognitive Neurology at BIDMC. "But, it turns that out our brain is changing all the time. It's making new cells continuously. It's rewiring the connections between cells that we call synapses — they're changing, literally, thousands of times per second. So, everything we do and experience changes our brain. We call this neuroplasticity and it's what allows our brains to adapt as we age."

4. Dreams Help You Form Memories

In a recent study at BIDMC, individuals spent time working on a memory task navigating through a virtual maze. After an hour of working on the task, half of the participants took a nap, the other half rested quietly, but stayed awake. When they returned to the task, only the nappers who reported that they had dreamed performed better when repeating the task.

"What got us really excited is that after nearly 100 years of debate about the function of dreams, this study told us that dreams are the brain's way of processing, integrating and really understanding new information," says Dr. Robert Stickgold, Director of the Center for Sleep and Cognition. "Dreams are a clear indication that the sleeping brain is working on memories at multiple levels, including ways that will directly improve performance."

5. Your Brain is an Energy Hog!

Our brains account for only about two percent of our total body weight, but consume a gluttonous 20 percent of the body's energy. Further, this high rate of energy use remains nearly constant regardless of whether we're tackling a tough physics problem or sitting quietly, flipping through a magazine.

"The resting brain consumes almost as much energy as an active brain," says Dr. Michael D. Fox, a neurologist in the Berenson-Allen Center for Noninvasive Brain Stimulation and the Parkinson's Disease and Movement Disorders Center at BIDMC. "Most of what our brain is doing is spontaneous activity that has no clear relationship to external stimuli or the actions we're busy with."

6. There's a Reason Some Things are "Just Like Riding a Bike"

Whenever you use the phrase "it's just like riding a bike," you have your basal ganglia to thank for it. These enigmatic structures deep inside your brain contain large numbers of neurons, or nerve cells that are essential for behavior related to movement.

"The basal ganglia probably play an important role in taking an action or behavior you learn very deliberately at first, like a golf swing, and converting it to an almost automatic behavior over time with practice," says Dr. Ludy Shih, a neurologist in BIDMC's Parkinson's Disease and Movement Disorders Center. "With diseases like Parkinson's that affect the basal ganglia, once automatic movements become more difficult. We can use our understanding of basal ganglia to explore ways in which rehabilitation or other interventions can help reengage the brain to restore movement and ability."

7. Meditation can Change Your Brain for the Better — Really!

A recent study found that as little as eight weeks of meditation has the power to increase gray matter in areas of the brain associated with memory, compassion and focus, and can reduce the size of the amygdala, the area of the brain associated with the fight or flight response.

"This is some concrete evidence that the stress relief and brain boost meditators have been reporting for years has a real biological basis in the changes meditation produces in the neural pathways of the brain," says Dr. Aditi Nerurkar, an integrative medicine physician.

Dr. Nerurkar prescribes meditation for the patients she treats for stress. She also recommends unplugging from electronic devices. "Overuse of the internet can cause a phenomenon called 'popcorn brain,'" she says. "Think about how helpful it can be to power down our devices from time to time. It should come as no surprise that it's important to unplug our brains too."