What are brainwaves?
The brain has billions of neurons, and each individual neuron connects (on average) to thousands of others. Communication happens between them through small electrical currents that travel along the neurons and throughout enormous networks of brain circuits. When all these neurons are activated they produce electrical pulses – visualize a wave rippling through the crowd at a sports arena – this synchronized electrical activity results in a “brainwave”.
When many neurons interact in this way at the same time, this activity is strong enough to be detected even outside the brain. By placing electrodes on the scalp, this activity can be amplified, analyzed, and visualized. This is electroencephalography, or EEG – a fancy word that just means electric brain graph. (Encephalitic, the brain, is derived from the ancient Greek “encephalitis,” meaning within the head.)
One way that EEG ‘brainwaves’ convey information is in their rate of repetition. Some oscillations, measured on the scalp, occur at more than 30 cycles per second (and up to 100 cycles per second!) These cycles, also called frequencies, are measured as Hz, or hertz, after the scientist who proved the existence of electromagnetic waves.
When looked at this way, brainwaves come in five flavors, each of which corresponds to a Greek letter. As we’ll see, these different brainwaves correspond to different states of thought or experience. While there are many other ways to analyze brainwaves, many practitioners of a field called neurofeedback rely on dividing brain oscillations into these five categories.
Some of these brain oscillations are more easily detectable on specific parts of the scalp, corresponding to the parts of the brain just below. The brain has many specialized regions which correspond to different processes, thoughts, and sensations. Particular oscillations often reflect distinct regions and networks in the brain communicating with each other.
Brain waves and meditation
Forget about crystals and candles, and about sitting and breathing in awkward ways. Meditation research explores how the brain works when we refrain from concentration, rumination and intentional thinking. Electrical brain waves suggest that mental activity during meditation is wakeful and relaxed.
“Given the popularity and effectiveness of meditation as a means of alleviating stress and maintaining good health, there is a pressing need for a rigorous investigation of how it affects brain function,” says Professor Jim Lagopoulos of Sydney University, Australia. Lagopoulos is the principal investigator of a joint study between his university and researchers from the Norwegian University of Science and Technology (NTNU) on changes in electrical brain activity during non-directive meditation.
Constant brain waves
Whether we are mentally active, resting or asleep, the brain always has some level of electrical activity. The study monitored the frequency and location of electrical brain waves through the use of EEG (electroencephalography). EEG electrodes were placed in standard locations of the scalp using a custom-made hat
Participants were experienced practitioners of Ac-em Meditation, a non directive method developed in Norway. They were asked to rest, eyes closed, for 20 minutes, and to meditate for another 20 minutes, in random order. The abundance and location of slow to fast electrical brain waves (delta, theta, alpha, beta) provide a good indication of brain activity.
Relaxed attention with theta
During meditation, theta waves were most abundant in the frontal and middle parts of the brain.
“These types of waves likely originate from a relaxed attention that monitors our inner experiences. Here lies a significant difference between meditation and relaxing without any specific technique,” emphasizes Lagopoulos.
“Previous studies have shown that theta waves indicate deep relaxation and occur more frequently in highly experienced meditation practitioners. The source is probably frontal parts of the brain, which are associated with monitoring of other mental processes.”
“When we measure mental calm, these regions signal to lower parts of the brain, inducing the physical relaxation response that occurs during meditation.”
Meditation: Learn to Slow Down Your Brain Waves
There are five major categories of brain waves, each corresponding to different activities we do. Meditation enables us to move from higher frequency brain waves to lower frequency and calm the mind. Slower wavelengths allows for more time between thoughts which then offers us more opportunities for to skillfully choose the thoughts we invest in. Let’s break down the five categories of brain waves:
- Gamma State – The brain waves are at frequencies ranging from approximately 30 to 100Hz. This is the state of hyperactivity in the brain and active learning. Gamma state is the most opportune time to retain information. This is why Tony Robbins and other educators have audiences jumping up and down or dancing around – to increase the likelihood of permanent assimilation of information and lasting change in one’s “state.” If overstimulated, it can lead to anxiety.
- Beta State – This is where we function for most of the day. Beta is associated with the alert mindstate of the prefrontal cortex. Brain wave frequencies in this state range from 13 to 30Hz and this is a state of the “working” or thinking mind: analytical, planning, assessing and categorizing.
- Alpha State – Brain waves in the Alpha state range from 9 to 13Hz. This is the state where brain waves start to slow down out of thinking mind. We become more calm, peaceful and anchored. We often find ourselves in an alpha state after a thorough yoga class, a walk in the woods, a pleasurable sexual encounter or during any activity that helps relax the body and mind. We are lucid, reflective, have a slightly diffused awareness and at peace. This is often accompanied by an inner and/or outer glow. The hemispheres of the brain are more balanced.
- Theta State – When brain waves range from 4 to 8Hz in the Theta state, we are able to begin meditation. This is the point where the verbal/thinking mind transitions to the meditative/visual mind. We begin to move from the planning mind to a deeper state of awareness (often felt as drowsy), with stronger intuition, more capacity for wholeness and complicated problem solving. The Theta state is associated with the sixth chakra (third eye), so in this state we are able to practice visualization.
- Delta State – The final state is the Delta state, where brain waves range from 1 to 3 Hz. Tibetan monks that have been meditating for decades can reach this in an alert, wakened phase but most of us reach this final state during deep, dreamless sleep.
A simple meditation to use to begin the transition from Beta or Alpha to the Theta State is to focus on the breath. The breath and mind work in tandem, so as breath begins to lengthen, brain waves begin to calm and slow down. Try this:
- To begin the meditation, sit comfortably in your chair with your shoulders relaxed and spine tall. Place your hands mindfully on your lap, close your eyes and as much as possible eliminate any stimulus that may distract you.
- Watch your breath. Simply notice your breath flowing in. Flowing out. Don’t try to change it in any way. Just notice.
- Silently repeat the mantra: “Breathing In. Breathing Out.” As your mind begins to wander, draw it back to your breath. Notice that as your breath begins to lengthen and fill your body, your mind begins to calm.
What are Brainwaves?
At the root of all our thoughts, emotions and behaviors is the communication between neurons within our brains. Brainwaves are produced by synchronized electrical pulses from masses of neurons communicating with each other. Brainwaves are detected using sensors placed on the scalp. They are divided into bandwidths to describe their functions (below), but are best thought of as a continuous spectrum of consciousness; from slow, loud and functional – to fast, subtle, and complex. It is a handy analogy to think of brainwaves as musical notes – the low frequency waves are like a deeply penetrating drum beat, while the higher frequency brainwaves are more like a subtle high pitched flute. Like a symphony, the higher and lower frequencies link and cohere with each other through harmonics. Our brainwaves change according to what we’re doing and feeling. When slower brainwaves are dominant we can feel tired, slow, sluggish, or dreamy. The higher frequencies are dominant when we feel wired, or hyper-alert. The descriptions that follow are only broad descriptions – in practice things are far more complex, and brainwaves reflect different aspects when they occur in different locations in the brain. Brainwave speed is measured in Hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.
Infra-Low brainwaves (also known as Slow Cortical Potentials), are thought to be the basic cortical rythms that underlie our higher brain functions. Very little is known about infra-low brainwaves. Their slow nature make them difficult to detect and accurately measure, so few studies have been done. They appear to take a major role in brain timing and network function.
Delta waves (.5 to 3 Hz)
Delta brainwaves are slow, loud brainwaves (low frequency and deeply penetrating, like a drum beat). They are generated in deepest meditation and dreamless sleep. Delta waves suspend external awareness and are the source of empathy. Healing and regeneration are stimulated in this state, and that is why deep restorative sleep is so essential to the healing process.
Theta waves (3 to 8 Hz)
Theta brainwaves occur most often in sleep but are also dominant in deep meditation. Theta is our gateway to learning, memory, and intuition. In theta, our senses are withdrawn from the external world and focused on signals originating from within. It is that twilight state which we normally only experience fleetingly as we wake or drift off to sleep. In theta we are in a dream; vivid imagery, intuition and information beyond our normal conscious awareness. It’s where we hold our ‘stuff’, our fears, troubled history, and nightmares
Alpha Brain Waves Boost Creativity and Reduce Depression
Neuroscientists recently made a correlation between an increase of alpha brain waves—either through electrical stimulation or mindfulness and meditation—and the ability to reduce depressive symptoms and increase creative thinking.
Our various states of consciousness are directly connected to the ever-changing electrical, chemical, and architectural environment of the brain. Daily habits of behavior and thought processes have the ability to alter the architecture of brain structure and connectivity, as well as the neurochemical and electrical neural oscillations of your mind.
In previous posts, I’ve written about how neurocysticercosis and neurogenesis (growth of new neurons) can alter the architectural connectivity between brain regions and increase brain volume, which directly impacts cognitive function. I’ve also explored how the “neurochemicals of happiness”—endorphins, endocrinologists, dopamine, serotonin and oxytocin—can make us feel good when we do things like exercise and spend time with loved ones by changing the chemical environment of the brain. In this post, I focus on the electrical environment of the brain and recent discoveries on how brain waves fine-tune our consciousness based on new findings that stimulating alpha waves can boost creativity and reduce depression.
The Connection Between Brainwaves And Meditation
You might hear the word “brainwaves” a lot. But what are they? Why do we have them? What do they do? What is the science behind brainwaves?
Scientists and clinicians use brainwaves to measure and understand the functioning of the brain. We typically can’t see them, but human brains have billions of neurons. These individual neurons connect to thousands of other neurons. And when brain activity happens, these neurons light up much the same way thousands of audience members do “the wave” in an arena.
This synchronized electrical current is strong enough that scientists are able to detect it by using electroencephalography, or EEG.
Brain waves are measured in cycles per second, known as Hertz or Hz for short. When the number of Hz is lower, that means that the brain activity happening is slower.
When they first started to identify different types of brainwaves in the 1930s and 1940s, they found 4 types:
- Alpha waves (8-13 Hz) occur when we’re in a relaxed and calm state.
- Beta waves (13-38 Hz) occur when we are actively thinking or problem-solving.
- Delta waves (below 4 Hz) occur during our sleep cycle.
- Theta waves (4-7 Hz) occur during the sleep cycle as well and are associated with deep relaxation and visualization.
Now, scientists have added more common brain waves to the list, but one that is most important to personal actualization is:
- Gamma brain waves (39-100 hz) occur during higher mental activity and consolidation of information
One interesting study showed that advanced Tibetan mediators produce higher levels of Gamma waves than non-mediators — even after they spent the same amount of time meditating.
So does that mean that there are certain types of brainwaves that are better? The short answer to that question is that each brainwave has a different function. During the day, you might want to produce a certain kind of brainwave more frequently or during different times and activities. That requires a certain amount of control, flexibility, and resilience.
You need control so that you can enter a certain state when you want to. For example, if you’re working on solving a particular math problem, you’d want to be in a state of alpha and not delta (deep sleep).
You need flexibility so that you can move from one state to another easily. You definitely want to be able to transition out of alpha and into a more relaxed state, like beta, if you’re getting a massage.
And finally, you need resilience. You want to be able to return to a state you were originally trying to stay in. For example, if you’re practicing restorative yoga and all of a sudden you find yourself working out a financial problem, you’d want to be able to return to the practice of relaxing your body.
We’ve put together all the basic information you need to know in one info graphic (and a special treat below).