When tuning instruments that can produce sustained tones, beats can be readily recognized. Tuning two tones to a unison will present a peculiar effect: when the two tones are close in pitch but not identical, the difference in frequency generates the beating. The volume varies like in a tremolo as the sounds alternately interfere constructively and destructively. As the two tones gradually approach unison, the beating slows down and may become so slow as to be imperceptible. As the two tones get further apart, their beat frequency starts to approach the range of human pitch perception[1], the beating starts to sound like a note, and a combination tone is produced. This combination tone can also be referred to as a missing fundamental, as the beat frequency of any two tones is equivalent to the frequency of their implied fundamental frequency.
Women worry more than men do. A study of 166 married couples who kept stress diaries for six weeks found that women feel stress more frequently than men because women tend to worry in a more global way. Whereas a man might fret about something actual and specific—such as the fact that he's just been passed over for a promotion—a woman will tend to worry abstractly about her job, her weight, plus the well-being of every member of her extended family. Keep your anxiety focused on real, immediate issues, and tune out imagined ones or those over which you have zero control, and you'll automatically reduce stress overload.
Today we're going to put on our headphones, kick back in the beanbag, and get mellow to the soothing sounds of the latest digital drug: binaural beats. These computer generated sound files are said to massage your brain and produce all sorts of effects, everything from psychedelic experiences to behavior modification. Let's point our skeptical eye at the science of binaural beats, and especially at some of the claims made for them.

For a little variety, you can use the 60 minute Delta Ultra Deep Standalone Meditation which takes you down into Delta and holds you there for an extended period of time. If you can stay awake during this entire time, you will have some amazing meditative experiences. (If you fall asleep, don't worry! It's natural and with practice you will be able to stay awake more often.)
Theta is very subtle. It is one of the most elusive and extraordinary brain states you can explore. Theta is a state of somnolence with reduced consciousness; you are neither fully awake nor asleep yet. It is also known as the “Twilight state” or “Stage 1 Sleep” which you normally only experience fleetingly as you wake or drift off to sleep. In the Theta brain state, your senses are withdrawn from the external world and focused on signals originating from within.
When your mind is all over the place, organizing your thoughts into a quick to-do list can help transfer the burden from your brain to paper. But for some people, seeing a long list of tasks can increase stress. Miller has another idea: a “stressor and action” sheet. “Fold a piece of paper in half length wise, and on the left column write ‘stressor’ and on the right hand column write ‘action,’” she says. “You will find as you write down thoughtful action steps to the things that are stressing you out, you regain authority over circumstance.” These are the signs you’re more stressed than you realize.

Participants in the included studies were children and adults, either healthy or with conditions such as learning disabilities, attention deficit hyperactivity disorder, migraine, stress, anxiety and myofascial pain. Interventions included single, alternating, ascending or descending frequencies of photic or auditory stimulation or audiovisual entrainment selected either by the participant or by the investigator. Nearly half the studies used single sessions and the rest used multiple sessions ranging from nine to 100. Length of session varied from 0.5 seconds to 60 minutes. Frequency of session varied from twice daily to weekly. Outcomes reported in the review included cognition (including verbal skills, performance skills, attention, memory and overall intelligence/achievement), short- and long-term stress, pain, headache/migraine, mood, behavioural problems and premenstrual syndrome (PMS).

When you hit a tuning fork, tuned to a particular sound frequency such as the note B, and hold it close to the strings of a guitar, you will notice that the B string on the guitar will vibrate because it has entrained on to the same frequency of the tuning fork. Interesting enough, the other strings will not vibrate. Only the one with the same tuning as the tuning fork.
a past history of trauma. When faced with stressful situations, you may find yourself totally stuck and unable to take action. Your challenge is to break free of your “€œfrozen”€ state by rebooting your nervous system and reactivating the body’s natural “€œfight-or-flight”€ stress response. Physical movement that engages both your arms and legs, such as walking, swimming, running, dancing, climbing, or tai chi, can be particularly helpful. As you move, focus on your body and the sensations you feel in your limbs rather than on your thoughts. This mindfulness element can help your nervous system become “unstuck” and move on.
When your mind is all over the place, organizing your thoughts into a quick to-do list can help transfer the burden from your brain to paper. But for some people, seeing a long list of tasks can increase stress. Miller has another idea: a “stressor and action” sheet. “Fold a piece of paper in half length wise, and on the left column write ‘stressor’ and on the right hand column write ‘action,’” she says. “You will find as you write down thoughtful action steps to the things that are stressing you out, you regain authority over circumstance.” These are the signs you’re more stressed than you realize.
If you’re going to enter a state of meditation, a technique of some sort must be employed that takes you there. (Note – I am fully aware of references to “spontaneous enlightenment experiences”, but these are an entirely different category of phenomena than what is being discussed here and are outside the scope of this discussion. Perhaps another time.)

Unlike many traditional therapies for dealing with stress, anxiety, depression or cognitive impairment, entrainment does not require a focused effort from the person having the therapy, as the brain instinctively follows the frequency. This makes it a much more effective therapy for managing some of these challenging conditions, by automatically inducing a sense of relaxation and a reduction in negative physical and emotional patterns.
Summaries from recent reviews on yoga or Tai Chi clinical trial interventions indicate that these mind-body types of exercise can be effective in reducing stress (7,14,17). The authors of these reviews suggest that the results should be viewed with caution because study quality was varied (7,17). However, it should be noted that reductions in stress reported in one review were similar to or greater than reductions from other types of commonly used stress management techniques (7).
When we first use brainwave entrainment, we may not have anything specific in mind that will happen, but we hold a general expectation that “something” should happen. As we begin the process of entrainment we are on high alert looking for any little indication that something is happening. Pretty soon we identify some feeling or twitch or unusual perception. The moment we focus on whatever it is, the act of focusing on it magnifies the thing. Since we were already viewing the situation with an expectation that it was the entrainment that was going to produce some sort of result, we automatically associate whatever our phenomenon is with entrainment.

In one study, researchers had a group of participants relax alone in a quiet, low-light environment following an exercise session. They split the group in two — one spent 20 minutes listening to theta-frequency binaural beats while the other listened to a carrier tone and monitored their parasympathetic (rest and relaxation) and sympathetic (fight or flight) nervous system activity. Researchers found the group that listened to binaural beats experienced an increase in parasympathetic activity and a decrease in sympathetic activity, along with higher rates of self-reported relaxation.
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. 

The various mental states of the individual are thought to take place across a varied range of frequencies, or brainwaves. By encouraging the frequency following process, entrainment is able to create positive change in the brain, through matching carefully-selected frequencies of light and/or sound. The stimulus enables the individual to access a different state of consciousness, which can be useful for a number of benefits including relaxation, anxiety management, stress reduction and more.
These sounds in these musical tracks are presented through monaural beats, binaural beats, isochronic tones, or a mixture involving combinations of all three of these modalities, described in detail below. Choose alpha brainwave tracks for calming anxiety and relaxing body and mind, and choose theta tracks for help in getting to sleep and for bringing hidden feelings to the surface. Some people also report out-of-body type experiences when in theta brainwave states.
A therapy that slows brainwave activity, helping to produce low-frequency waves, is likely to aid relaxation and sleep. But it’s not only lowering brainwave frequency that binaural beats may offer to sleep and relaxation. A small study (19 people) has found that exposure to binaural beats is associated with changes to three hormones important to sleep and well being:
Your brain cells reset their sodium & potassium ratios when the brain is in Theta state. The sodium & potassium levels are involved in osmosis which is the chemical process that transports chemicals into and out of your brain cells. After an extended period in the Beta state the ratio between potassium and sodium is out of balance. This the main cause of what is known as "mental fatigue". A brief period in Theta (about 5 - 15min) can restore the ratio to normal resulting in mental refreshment.  
That’s why it’s so important to find the proper stress relievers to maintain a strong quality of life. The eight stress relievers above — exercise and yoga, meditation/healing prayer, acupuncture, a nutrient-dense diet, cognitive behavioral therapy, spending more time in nature and being social, keeping a journal and using adaptogen herbs and essential oils — can help you maintain a good mood, remain calm and better handle your day-to-day stress.

You’ve heard the “om” sound yogis make when they meditate, right? Well, Joshi says using a buzzing sound is another way to use your voice to calm yourself in the midst of a freakout. “Bhramari, a humming bee sound, can be done by closing the eyes and making the humming sound like a bee,” she says. “These sound vibrations calm down the thought waves and relax the entire nervous system. External sound frequency resonates with the internal rhythm of the body and mind, creating peace and tranquility within.” Research from India has shown Bhramari to improve cardiovascular patterns. Press your ears closed for an even stronger vibration.

These brainwaves are actually a bit of a mystery. They’re the highest frequency you can achieve, but scientists are a little dumbfounded by them. Unlike the next set of brainwaves (Alpha and Beta), Gamma brainwaves don’t’ really translate to feeling active and alert. Rather, what’s been discovered is that in Gamma, neurons are firing so harmoniously, that people often feel like they are having a spiritual experience. This brainwave state has been associated with expanding consciousness and understanding the value of universal love and harmony.
A more extensive study of over 100 participants who were undergoing general anesthesia for a day procedure, reported a decrease in pre-operative anxiety. The participants in this study listened to 30 minutes of binaural beats before surgery, but the researchers noted that people experiencing high levels of pre-operative anxiety could listen to binaural beats for up to 1 hour before anesthesia to reduce levels of anxiety.
Deep breathing is an easy stress reliever that has numerous benefits for the body, including relaxing muscles and quieting the mind. Breathing exercises are especially helpful because you can practice them anywhere. Perhaps more importantly, they work quickly so you can de-stress in a flash. The ​​​karate breathing meditation is a great exercise to start with, and this basic breathing exercise can be done anywhere to help you reverse your ​stress response, get back to being more proactive (rather than reactive), and face stress with greater resilience.
A simple spinal twist can help you get a better night's sleep. It alleviates tension that's built up in your lower back throughout the day. Sitting on your bed with legs crossed, place your right hand down on the bed behind you and rest your left hand on your right knee. Sit up straight and inhale for four to eight counts, lengthening your spine as you breathe. On your exhale, begin to twist toward your right hand (don't strain your neck). Hold this position for four more full breaths, lengthening your spine on the inhales and deepening your twist on the exhales, if it feels comfortable. Repeat yoga asanas on opposite side. (These stress-reducing yoga poses also help calm anxiety.)
Alpha is the next level down, between 8Hz - 12Hz, corresponding to being awake but deeply relaxed. It can be a little confusing that Alpha is lower than Beta, but it is named that way because Alpha was the first brainwave "discovered" (identified) by Hans Berger in 1929. Meditating in this state is very relaxing and most people find it very easy to become entrained in this frequency.
This is probably the most popular choice of frequency. The theta state is a state of tremendous stress relief. The benefits associated with theta level relaxation include improved concentration, reduced hyperactivity and improved memory. While in a state of theta relaxation, one’s blood pressure, breathing and heart rate all slow to a much more restful and healthy level that promotes natural healing. During theta relaxation one may also experience vivid flashes of mental imagery as the mind opens to memories or subconscious information that is not available to the conscious mind during the normal waking state. The theta state is a very deep state of relaxation that is excellent for deep hypnosis and mental programming.

With the binaural beats, this may be difficult to do since you need to listen to the twin frequencies and allow your brain to create a third one to bridge the gap. Ideally, you will be listening to these beats through headphones so carrying out other work may be challenge. However, with isochronic frequencies, the tone can be heard without headphones which means you can run the mp3 with a speaker and allow it to play in the background as you carry out your work. Of course, activities such as driving or operating heavy machinery should NOT be undertaken when you are listening to these tones because your attention is shared between the two tasks. Tasks like gardening or sewing or cooking can be done while your brainwave entrainment music is playing.
No, it isn’t, at least not in the way these people are thinking. Neither would any other entrainment product you could purchase for that matter. Part of the problem is the proliferation of utter nonsense about brainwave entrainment one can read all over the internet. There is one site in particular that comes to mind, and the contents of that site are often copied by other websites. It is a list of Hz frequencies with their corresponding (alleged) physical effects. The list runs on for many pages. I won’t bother with the link because you can Google it and find it for yourself if you feel the need for a good laugh, but here are some examples regarding meditation and brainwave entrainment from this site:

♥ At 56, I have tried many a thing. The default setting of Binaural Beat Machine does make me very relaxed. But it's not what it does on the moment, pleasant as this might be. It is the quality of the sleep, when I use it for half an hour before going to bed. I sleep a deep, restful sleep. I use it during day-time meditation as well, and the clear-mind feeling about an hour later is wonderful!

Building on guided imagery, you can also imagine yourself achieving goals like becoming healthier and more relaxed, doing well at tasks, and handling conflict in better ways. Also, visualizing yourself doing well on tasks you’re trying to master actually functions like physical practice, so you can improve your performance through ​​visualizations as well.
Isochronic tones work by influencing your brainwave activity and they can’t directly affect the body. That said, the brain does control the body, so sensations and feelings can sometimes be felt in the body after stimulating your brainwave activity. Some people who are new listeners of this type of audio can sometimes feel tingling sensations in their body. Not everyone feels this and these sensations usually stop once you get more used to using the audios. Isochronic tones are considered as a safe technology. However, sometimes they can leave you feeling temporarily fatigued, especially if you listen to them for an extended period (hours) when you first start using them. If you felt fatigued, I would recommend using them for a much shorter period while you are getting used to them and ensure you are well-hydrated.
Synchronized brain waves have long been associated with meditative and hypnogogic states, and audio with embedded binaural beats has the ability to induce and improve such states of consciousness. The reason for this is physiological. Each ear is "hardwired" (so to speak) to both hemispheres of the brain (Rosenzweig, 1961). Each hemisphere has its own olivary nucleus (sound-processing center) which receives signals from each ear. In keeping with this physiological structure, when a binaural beat is perceived there are actually two standing waves of equal amplitude and frequency present, one in each hemisphere. So, there are two separate standing waves entraining portions of each hemisphere to the same frequency. The binaural beats appear to contribute to the hemispheric synchronization evidenced in meditative and hypnogogic states of consciousness. Brain function is also enhanced through the increase of cross-collosal communication between the left and right hemispheres of the brain.
So, what we’re doing is combining these two parts, the awakening of complete stillness and deep relaxation with the rhythmic sounds, and embedding all frequencies within the music from right at the upper limits of human hearing to the lower limits. There is multi-level entrainment within Journey—I’ve layered in everything I know about audio brainwave entrainment into this track. 
It’s not easy to remember to use your senses in the middle of a min€”or or not so minor crisis. At first, it will feel easier to just give into pressure and tense up. But with time, calling upon your senses will become second nature. Think of the process like learning to drive or play golf. You don’€™t master the skill in one lesson; you have to practice until it becomes second nature. Eventually you’€™ll feel like you’€™re forgetting something if you don’t tune into your body during challenging times. Here’€™s how to make it habit:
Researchers advise that people who suffer from epilepsy or seizures should ask for professional insight first before using binaural beats. Pregnant women are also advised to seek the advice of their physicians. However, I haven’t heard anything about binaural beats impacting those who have had heart attacks negatively. That being said, I encourage you to do extra research.
Binaural beats are created from two different continuous tones, which when sent separately to each ear create a single beat inside your head. Isochronic tones are basically a single tone which is switched on and off at regular intervals. Imagine a single continuous tone playing on a stereo system and you’ve got your hand on the volume switch. Then once per second, you turn the volume off for half a second and keep doing that every second. For half a second the volume is off, for the other half a beat waveform is formed. The beat is cycling once per second per second, i.e. at a rate of 1Hz.

Research: the authors stated that qualitative electroencephalogram signatures needed to be developed for different disorders and tested using standard validated methods of psychological assessment. Larger RCTs were needed with clear inclusion criteria for participants. The RCTs should measure qualitative EEG, hormone levels and the time of day of the intervention. Interventions protocols should be clearly defined and the relationship between session frequency/ duration and outcomes should be explored. More studies of auditory stimulation were needed, as well as studies comparing different types of stimulation, monaural, binaural and isochronic beats and use of white noise versus music.