While visual entrainment is more powerful than audio alone for inducing desired brainwave states, more caution is needed when using visual methods. Between 0.3 and 3 percent of the population is susceptible to having seizures from flickering light stimulation, and for other people, flickering visual stimuli simply makes them uncomfortable. People with epilepsy have a greater chance of having a seizure from exposure to flickering light stimulation.
Hello Jason, this is an unusually thoughtful discussion. Thank you for all your expertise and your kind manner of presenting and moderating it. I’m wondering if you have any experience with this: ever since I’ve been exposed to theta wave music, without headphones, I have found it irritating. And this is in spite of the fact that when I was first handed a CD by someone I knew well and trusted he was so confident I’d love it It didn’t occur to either of us that I might not. This happened again recently, which is about 10 years later, when I heard it playing overhead at an acupuncture clinic. I felt restless and even irritated, unable to zone out, which is unusual for me, during the treatment. I realized that the quality of my irritation was similar to what I’d felt listening to that CD a decade ago.So I asked if it was theta wave music and she said yes. The acupuncturist said that some people, but a vast minority, really dislike the music. She said that the few people who dislike it are not simply neutral, but actively dislike it. And she also said, but most people like it a lot. I’m just wondering what kind of factors might be present that would make a person feel so irritated by this music?
In shamanic traditions, drums have long been used to transport the shaman out of his or her body into other realms of reality through the use of constant rhythmic vibrations. Researcher Melinda Maxfield, studying the Shamanic State of Consciousness, found that the steady rhythmic beat of the drum struck 4.5 times per second was the key to transporting a shaman into the deepest part of his shamanic state of consciousness. With the invention of the EEG (electroencephalograph) Biofeedback researchers discovered that theta brain waves oscillate at 4.5 beats, or cycles, per second. In direct correlation, we see similar effects brought on by the constant and rhythmic drone of Tibetan Buddhist chants that transport the monks and even other listeners into realms of blissful meditation.

You’ve heard me talk before about how sound can make a difference to sleep. Patients often tell me that they fall asleep to relaxing music, they seem to find it really helps them let go of active thoughts and quiet their mind—which, like yours probably does, tends to race from one thing to the next all day long (aka I can’t turn off my brain syndrome).
Since opening their online store in 2011, Binaural Beats Meditation has served “hundreds of thousands” of customers, according to James Matthews, the site’s customer happiness manager. “We continue to see an increase in interest… from individuals, but increasingly so from therapists using the music to help clients, health and wellness organizations, and businesses around the world.”
There’s a growing body of research suggesting that binaural beats can reduce different forms of anxiety, from mild to chronic. One especially interesting study looked at the effects of binaural beats on anxiety among patients preparing to undergo surgery—a life circumstance that is pretty anxiety provoking for most anyone. Over a period of six months, patients spent 30 minutes on the day of their surgery listening to binaural beats. Compared to patients who listened to a soundtrack that did not include binaural beats—and patients who received no “beats” therapy at all—the binaural beat listeners experienced significantly greater reductions in their anxiety levels.
Theta: This brainwave pattern is associated with deep relaxation and with some stages of sleep, including the lighter stages of non-REM (NREM) sleep. REM sleep itself is mostly composed of beta wave and other activity that’s similar to an alert, waking brain. Deep meditation produces theta waves, which are slower and lower frequency (between 5-8 hertz) than Alpha waves. That murky barrier between sleep and wakefulness, when you’re drifting in and out of sleep, and your thoughts feel dreamlike and difficult to remember? That’s a theta-dominant state of consciousness.
Despite the lack of solid evidence of the effectiveness of binaural beats in producing brainwave changes, and that those changes can be effective in altering our conscious states, there do exist hours of recorded binaural beat videos available on YouTube. Some of these are just straight beats designed to ease the listener into various states by gradually varying the frequencies of the beats. A nice example of this can be found in a 90-minute video by Jody Hatton. Others embed the beats into a musical score, which some people find easier to listen to. Spotify has a whole playlist devoted to binaural beats. You can try these and many others to see if this is something that may be helpful to you. The soothing nature of the sounds may be what really helps, but that’s fine if you just want to relax and drift off to sleep. You can also find quite a few apps that generate binaural beats at your phone’s app store. If you want to relax and sleep just be sure to set the frequency in the theta range (4 – 7 Hz). Patients have reported to me that they felt energized or even anxious after listening to a few minutes of the beats, but this was usually because they were set to a high frequency like beta (13 – 16 Hz). Be sure to try listening to the beats for a short time and if they have a negative effect, just stop listening. If you find them helpful, that’s great, and you have a new technique that can be used to promote relaxation, something most of us can use. 
The use of brainwave entrainment techniques offers many benefits for overall health and well-being, including improved emotional stability, increased cognitive function, and a deepening of creative insight. Much of this benefit derives from the hemispheric synchronization occurring as a result of entrained brainwaves. This effect happens when the electrical impulses in both hemispheres synchronized to the same frequency being delivered through the entrainment source.

A binaureal beat is created by playing a different tone in each ear, and the interference pattern between the slightly differing frequencies creates the illusion of a beat. It's intended to be heard through headphones, so there's no cross-channel bleed across both ears. Listen to this, I'll play a simple binaural beat, and I'll slide the pan control back and forth from one ear to the other. You can see that there isn't actually any beat, it's just an acoustic illusion: