Other entrainment methods sometimes used include autopan modulation that moves sound in an 180º arc to create a desired tone. Harmonic box entrainment, invented by James Mann, uses a layering of binaural and monaural tones that alternate between ears, requiring headphones. Sound modulation and filtering, amplitude modulation, and pitch panning use diverse sounds to create rhythmic pulses matched to the desired brainwave frequency. 

All brainwave frequencies are useful and beneficial at certain times – there is no brainwave that is intrinsically better than another. However, by deliberately choosing to attain a particular brainwave state, a corresponding mental state can be brought about at the same time. For example, a working person who has been in an overly alert beta brainwave pattern for many hours can quickly shift their mind and body into a relaxed state by listening to a few minutes of brainwave entrainment music for inducing alpha or theta brainwaves.
Learning: Since performance improves among those with ADHD and cognitive function may be boosted, one may hypothesize that learning would also improve. Those that are struggling to learn as a result of inattentiveness may benefit from stimulation with beta frequencies. Deficits in learning tend to be associated with abnormal or excess slow wave frequencies.
The only thing I have found lacking in using your product is that there is no place on your website to register my kudos to you for such an excellent product. I am not new to meditation, nor to brain entrainment products, and I found you product to be really outstanding. I’m completely hooked, love listening to the tracks and they are the best way ever to treat monkey mind. Bada boom, bada bing, in just a few minutes any aggravation I’m experiencing in the outside world, melts away and I am one very blissful and happy camper.
In 1984 medical researcher Dr. Gene W. Brockopp published a paper making several conclusions of audio and visual entrainment (AVE). Such conclusions were that hemispheric synchronization caused by AVE is related to increased intellectual functioning, practiced use of AVE overtime leads to a cumulative effect, and AVE may result in the recovery of early childhood experiences.
Sound and light are the most popular methods to entrain the mind, yet there are a few other options in our toolbox. Using vibrational energy from sources such as magnets and electricity has been proven to help overcome addictions, depression, and even treat neurological disorders such as Parkinson’s. In this section, we cover these alternative forms of brainwave entrainment.
Joseph Kao, creator of Journey to the Center of the Self, a deep, 30-minute, guided transpersonal meditation, accompanied by music embedded with advanced brainwave entrainment technology and followed by 30 minutes of only the brainwave entrainment music, talks with iAwake’s CEO, John Dupuy, about all that went into the making of this meditation tool masterpiece. Transcending and Including the Little Self John:           One thing I find so remarkable about your guided meditation in Journey to … [Read more...]
Hi Julie! You’re very welcome for the info. In answer to your question, I think some are probably good, and some not so good. There are many people putting brainwave entrainment out there these days and it is not so easy to figure out which ones are and aren’t of reliable quality without investing time and doing some research. I would say (in general) that paid products are probably better quality than free ones, but I couldn’t guarantee this is a golden rule. My best advice is to just do your research before spending too much time listening to the freebies.
All brainwave frequencies are useful and beneficial at certain times – there is no brainwave that is intrinsically better than another. However, by deliberately choosing to attain a particular brainwave state, a corresponding mental state can be brought about at the same time. For example, a working person who has been in an overly alert beta brainwave pattern for many hours can quickly shift their mind and body into a relaxed state by listening to a few minutes of brainwave entrainment music for inducing alpha or theta brainwaves.

Theta waves have another interesting characteristic. The Earth has a measurable resonance of 7.83 hertz known as the Schumann resonance. Because the Schumann resonance is a constant background frequency surrounding all life, it may play a special role in biological activity. The Schumann resonance frequency falls within the range of theta brainwaves and may have something to do with why these brainwave frequencies are so powerful. 


I also suffer with migraine for the last 15 years of my life. So, when I know I am going to have a headache I will start meditating and headache suddenly subsided. What an amazing thing you have created here. This is only three weeks of my experience. How much more what I can do after…………By the way I am 49 years old. I just want to thank you so very much for sharing this amazing tape with me. It is so worth it in all aspect. I wish you all the best. How I wish that our paths will cross one day.

Because each track is specifically aimed at attaining a certain outcome, you can pick exactly which track you want for what you want to do. This is great for beginners because you can start off with some simple tracks such as Instant Energy Boost or Endorphin Release. And then if you find you like them you can choose some of their more hardcore stuff (such as Lucid Dreaming or Shaman Consciousness).


That all said, we are all different and have our own different limits. So I generally advise that you just be aware of how you are feeling, and if you feel like you are getting a bit fatigued from it, it’s probably time to stop or at least take a break. When listening over long extended periods, I recommend that you keep yourself well-hydrated. Your brain needs a good supply of water to function well, especially if you are studying hard and increasing your brainwave electrical activity.
The brain produces electrical signals. These signals change depending on what we are doing and what mental state we are in. For instance when we sleep these signals are different from when we are awake. This brain activity can be measured with EEG. It will output in Hz (Hertz - cycles per second) these electrical signals. The most dominant brainwaves will tell us what sort of state a person is in. The slower vibration (lower Hz), the more relaxed that individual is. Using audio technology we get the brain to start following the beats or pulses in a sound if done exactly right.

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.
Thanks Lorita. There hasn’t been any isochronic tones research that I’m aware of, for anti-aging, fat loss or attracting people, or any significant anecdotal feedback. You could combine positive affirmations or hypnosis scripts with isochronic tones to try and change habits and that could help with fat loss or build confidence to attract people. But it would be the affirmations and hypnosis doing most of the work, the isochronic tones would just be used to help relax the listener and put them in a more suggestible state. I don’t believe isochronic tones can affect those things, without being used in combination with some kind of vocal mental programming.
All brainwave frequencies are useful and beneficial at certain times – there is no brainwave that is intrinsically better than another. However, by deliberately choosing to attain a particular brainwave state, a corresponding mental state can be brought about at the same time. For example, a working person who has been in an overly alert beta brainwave pattern for many hours can quickly shift their mind and body into a relaxed state by listening to a few minutes of brainwave entrainment music for inducing alpha or theta brainwaves.
Mood: While brainwave entrainment may not be a great option for depression, particularly in the slower frequency ranges, beta entrainment may improve certain measures of mood. Additionally it is important to consider the fact that many people experience detrimental changes in mood as a result of heightened stress and anxiety. Since brainwave entrainment has been shown to improve stress and relaxation, overstressed individuals may experience a simultaneous mood improvement.
I later learned that a Nobel Prize-winning scientist, Ilya Prigogine, had developed a theoretical model regarding the evolution of complex systems (like the human mind) that described these quantum leaps in awareness and brain-power I was experiencing—to a “T”—and explained why they happened! I read everything I could get my hands on about his work.
So I began to look at other instances in which the nervous system is being stimulated on a daily basis and discovered that sports science has a lot to teach us about this. Whether you are practicing yoga, meditation, using brainwave entrainment, or working out, it’s all pushing the nervous system. One of the things that sports science teaches us is that the nervous system waxes and wanes like a sine wave in its capacity to recover from, and grow from, the stimulation we give it every day. Static levels of stimulation, where you’re getting the same smack every day, day in and day out, do not allow for the fact that there are times when the nervous system is at its peak to handle the stimulation, and there are other times when the nervous system is in its trough, or valley period, when it is harder for it to recover from stimulation.

Sensorimotor rhythm (SMR) is one final type of brainwave that has been studied. SMR, also known as low beta, is a type of brainwave, which occurs in the sensorimotor cortex, in the 12 to 15 hertz range when that area of the sensorimotor cortex is idle and immobile. The purpose of SMR brainwaves is not well understood, but some neurofeedback practitioners report training to increase SMR brainwaves can be beneficial for people with autism, epilepsy, ADD, insomnia, drug addiction, and as an aide to better manage stress.
A very pleasurable experience during listening (and often for some time afterwards). As Holosync® changes your brain wave patterns to those of deep meditation, the brain produces several very pleasurable neurochemicals, including endorphins (the same endorphins responsible for “runner’s high”)…as well as several hormones with a profound and positive effect on longevity, aging, stress, and well-being.
Rather than discontinuing my meditation practice altogether, I instead began researching methods of increasing the effectiveness of meditative practice. This seemed an inevitable decision for me in light of the undeniable improvements I had witnessed in response to previous experience with meditation. This resulted in my eventual re-discovery of brainwave meditation programs brainwave synchronization. I had used a few different such products previously, but none that seemed effectively designed to meet my specific needs. After deciding to try a particular brainwave meditation program, I found it to greatly assist me in producing all of the previously experienced benefits of meditation, but in a shorter period of time and in a much more focused manner.
Every NeuralSync™ audio is recorded with full-range frequency sweeps that cycle rhythmically throughout the entire audio. The dynamics of the sweep are then additionally enhanced with simultaneous left-to-right channel crossing. Because of this augmentation, the effects are multiplied, the intensity is amplified and the brain is drawn into the mental state more consistently and powerfully than with the static methods of other protocols.
We’ll use Holosync® to place you in an alpha brain wave pattern, that of focus, concentration, and accelerated learning. You’ll become completely absorbed in whatever you’re reading—or, for that matter, in anything you do requiring focus and concentration. And, you’ll remain refreshed even after hours of concentration. Quietude™ will dramatically increase your productivity and learning ability.
Sound and light are the most popular methods to entrain the mind, yet there are a few other options in our toolbox. Using vibrational energy from sources such as magnets and electricity has been proven to help overcome addictions, depression, and even treat neurological disorders such as Parkinson’s. In this section, we cover these alternative forms of brainwave entrainment.
Thanks for the coupons, I had originally looked into these cd’s after my doctor recommended them, but my mom wound up buying them for me for Christmas (she didn’t know about the coupons I had!) Anyway just listened to Equisync II today for the first time, I was in such a state as to where I didn’t know if I’d fallen asleep or not! I hadn’t but was in such an amazing place.
Alpha stimulation: Stimulation of alpha waves has been shown to provide stress-relief among employees, is able to provide pain relief, and improve measures of competence and recognition. If you have significant work-related stress, entraining certain alpha frequencies may help you decrease arousal and improve relaxation. Post-surgical stress doesn’t appear to benefit from alpha stimulation.
Meditation enhancement: There are several companies that sell brainwave entrainment sessions specifically designed to enhance meditation. The sounds provide a stimuli to focus on during the meditation, and the brain waves naturally shift towards the frequency provided. Whether meditation is actually enhanced by brainwave entrainment is a subject of debate. However, advanced meditators commonly experience brainwave synchronization – which the right and left hemispheres display the same frequency brain waves.  While there are scientific benefits of meditation, it is unclear as to whether they are enhanced, hindered, or unaffected by adjunctive brainwave entrainment.
To get a full answer you should really get in touch with the owner of the app, because it does really depend on how their track is constructed and how they intend it to work. I have one 50-minute sleep track which takes you down into delta (http://www.mindamend.com/shop/sleeping-and-dreaming/sleep-induction-isochronic-tones/) and that is designed to just get you to sleep, so you just let play until the end. If you played that track on repeat it might make you jump and wake you up, as the track begins at a higher frequency. I have another 8-hour sleep track which is meant to be played all throughout the night (http://www.mindamend.com/shop/sleeping-and-dreaming/deep-sleep-8-hour-sleep-cycle/). So it does depend on the individual track you are using.
They use a proprietary process of ‘3 point dynamic audio entrainment’ which means that they use both binaural beats and isochronic tones, layered together with another process called temporal entrainment (the stretching and compressing of sound waves in order to speed up or slow down the brain). This 3 pronged effect on your brainwaves is very powerful, so powerful they are currently in the process of trying to patent it.
I have been making relaxation recordings for mental self help and health improvement since 1979. As a pathfinder in EEG ( brainwave monitoring and entrainment ) I understand totally the effects of sound and music on the human mind and body. The recordings offered from your website are without doubt some of the most effective I have ever used and recommend them to my clients whole heartedly

In March I started using the CDs that I affectionately call “Meditation for Dummies” and am very pleased with the results so far. My blood pressure has dropped, I am sleeping better and notice that I feel much more calm and less stressed. Instead of feeling that I need to “find the time” in my schedule to meditate, I look forward to that totally relaxing half hour–that peaceful feeling of floating.
Filed Under: Brainwave Entrainment, Creativity, Emotional Healing, Flow State, How to Let Go, iAwake Weekly Call, Life Optimization, Meaning of Life, Meditation Technology, Practice of Meditation, Spiritual Development, Waking Up Tagged With: Benefits of Brainwave Entrainment Meditation, Brain Entrainment Meditation, Brainwave Entrainment, Brainwave States, Changing Our Brains, Conscious Evolution, Daily Meditation Practice, Finding your purpose, Integral Recovery, Life Optimization, Meaning of Life, Overcoming Depression, practice of meditation, Spiritual Development, Stealing Fire, Stealing Flow, Waking Up
With regard to listening without headphones specifically, you might find it irritating if you are someone who suffers from motion sickness, depending on how the track is created. If you were listening to binaural beats, they really need headphones to work properly. If you are in a room and closer to one speaker you may not even hear binaural beats properly, and if sitting off centre in the room generally, that may have unsettled you if you have motion sickness as the tones try to form a beat in your head. If it was just a standard isochronic tones theta track that shouldn’t be irritating if you have motion sickness.

By the end of just a few short days (3 or 4 of use), my constant “on edge” feeling completely dissipated. I had changed my lifestyle drastically to a very low-stress environment. All feelings of anxiety disappeared rapidly, but I was still experiencing something “physical.” I had trouble explaining it to anyone. I lashed out immediately at the slightest frustration. I tried to explain to those around me that it was something physically happening in my brain, but they were skeptical. Within less than a week of using the EOC cd’s, I noticed my tolerance level for dealing with people and situations had increased tremendously.
“Binaural beats are not very noticeable because the modulation depth (the difference between loud and quiet) is 3 db, a two-to-one ratio. (Isochronic tones and mono beats easily have 50 db difference between loud and quiet, which is a 100,00-to-1 ratio). This means that binaural beats are unlikely to produce an significant entrainment because they don’t activate the thalamus.”

Brainwaves are the collective electrical signal of millions of neurons working together in a living brain, producing our sense of alertness – or lack thereof - and producing our experience of reality. As brainwaves change, so does our perception of the world and our inner perception of ourselves. By learning to control our brainwaves, we can achieve specific, desirable mental states, such as feeling more relaxed, less anxious, more creative, more focused, or sleepier.


I enjoy this one called: Cognition Enhancer For Clearer and Faster Thinking – Isochronic Tones (Electronic) … I seem to enjoy it. Any harm in just listening to this one every day for 30 minutes as a routine daily thing, just like brushing your teeth and making your bed. I would just use it at times when I’m working at my desk, maybe even reading the online news etc…Thoughts?

Hello Chip, I did a little research for you and it looks hopeful. “Even when a person is deaf binaural beats can work. By putting the headphones with the binaural recordings behind the ear, the sound waves travel to the brain through the scull and entrain the brain just the same.” I can not corroborate 100% that this id a fact, however, if you are willing to give it a go I would love to hear how this technique works for you. Please keep my updated as to your progress and results. ~ Maya


The brain is composed of millions of specialized cells called neurons. Neurons send signals to other neurons using electro-chemical messengers called neuro-transmitters that attach to receiving sites located on the neurons themselves. There is a space between the end of the neuron and the receptor called the synaptic gap. As neuro-transmitter chemicals move across this gap, a small electrical charge is created. 

Depression: Currently there is no substantial evidence to support the idea that brainwave entrainment treats depression in adults. Some evidence goes as far as to suggest that the wrong entrainment protocol (e.g. slow wave stimulation) may actually increase certain measures of depression. Stimulation of delta and/or theta, will likely worsen the condition and alpha is unlikely to have an effect.
Hello Chip, I did a little research for you and it looks hopeful. “Even when a person is deaf binaural beats can work. By putting the headphones with the binaural recordings behind the ear, the sound waves travel to the brain through the scull and entrain the brain just the same.” I can not corroborate 100% that this id a fact, however, if you are willing to give it a go I would love to hear how this technique works for you. Please keep my updated as to your progress and results. ~ Maya

Brainwave entrainment music can be used almost anywhere and anytime, making this mood and self-improvement method versatile and flexible enough to do at work, while traveling, or at other times during the day. When used in the workplace during short rest periods, brainwave entrainment techniques can enhance concentration, communication, and work productivity.
Good article. Richard, there are numerous studies dictating the research behind entrainment. Please see http://brainwavebooster.com/brainwave-entrainment-research/ for a list of many peer reviewed studies. The author here is totally correct in his labeling of brainwave entrainment as a therapy tool. Hope this helps. There are other studies out there as well, one only needs to Google it.
Because the mind and body are a single system, changing our brainwaves and spending more time in harmonious, relaxed, and restorative mind-states also affects our physical health. Physical health then reinforces our mental-state, and a feedback loop of either positive or negative processes becomes established. Research studies have shown beneficial effects of using brainwave entrainment for treating migraine headaches, premenstrual syndrome, and for managing physical pain.
I have never been more creative, productive, more loving to all people nor have I ever been happier in my life. All the wisdom I have found in my pursuit of happiness was somewhere in my intellect. Now it is a part of me. I am using it. I now consider myself a model for younger people to let them see how it is possible to function and be everything they’ve wanted to be. I just celebrated my 85th birthday and I am as young as when I was 25. Thank you for giving me the gift of my true self.

I’ve been on the brainwave vibe for about 6 months now, & I’m really diggin’ some results! I find that there are certain frequencies, I guess, that feel right and comfortable to my mind; I also find that I can physically feel the area of my brain that “pure” (no frikkn ocean waves) tones are affecting as I listen to them. This occurs the moment I hear the sound. Kinda like energy, a brain tickle. Spooky & awesome!!


The eyes of the participants were closed and the VFP goggles illuminated in alternative manner; first the right eye, then the left. The rate at which the photic stimulation was conducted ranged between 0.5 Hz and 50 Hz. Of the 50 patients with migraines, 49 considered their headache as having been “helped” by the stimulation and 36 noted that their headache had completely “stopped” from the VFP goggles.
I tried other companies the last few years or so….among the likes that mainly used binaural audio and the deepest I was really ever to achieve was alpha state….maybe theta once or twice over the last few years. It takes incredible dedication and practice to achieve the deep, renewing states of meditation that are most sought after…..I listened to the theta meditation mp3 last night and within what seemed like a few minutes my mind was flooded with imagery…memories long gone…my body was sleeping, heavy as lead, but my mind was crystal clear, aware of my surroundings. I could barely even open my eyes!

So I began to look at other instances in which the nervous system is being stimulated on a daily basis and discovered that sports science has a lot to teach us about this. Whether you are practicing yoga, meditation, using brainwave entrainment, or working out, it’s all pushing the nervous system. One of the things that sports science teaches us is that the nervous system waxes and wanes like a sine wave in its capacity to recover from, and grow from, the stimulation we give it every day. Static levels of stimulation, where you’re getting the same smack every day, day in and day out, do not allow for the fact that there are times when the nervous system is at its peak to handle the stimulation, and there are other times when the nervous system is in its trough, or valley period, when it is harder for it to recover from stimulation.
Scalar waves are a constantly regenerating energy source that imprint a signature on your body with lasting positive effects. They strengthen chemical bonds within DNA, making it more resistant to damage and cleanse blood and cells to improve immune function. They impart energy that helps mental focus, and increase amplitude of all EEG frequencies, but particularly the lower levels where deep rejuvenation, relaxation and healing occur. They leave you feeling refreshed and energized, with lasting pleasant sensations that continue long after each brainwave entrainment session.
By the 1980s, entrainment technology had merged with advancements in microelectronics technology, making it possible to develop even more sophisticated audio and visual brainwave entrainment products for the marketplace. In the last two decades, a number of scientific studies have reported brainwave entrainment as an effective remedy for ADD, academic learning problems, and improving memory and cognition.
Learning: Since performance improves among those with ADHD and cognitive function may be boosted, one may hypothesize that learning would also improve. Those that are struggling to learn as a result of inattentiveness may benefit from stimulation with beta frequencies. Deficits in learning tend to be associated with abnormal or excess slow wave frequencies.
Are you someone who has turned to meditation or yoga as a way of relieving stress and improving your overall well-being? Yoga and meditation are time-proven methods, used for centuries, which restore mental, physical, and spiritual balance in people’s lives, and brainwave entrainment can be used in conjunction with these practices for even deeper levels of benefit. 
I would like to share with you my experience after using EquiSync for three weeks. First of all, I am so amazed how fast I can put myself in a meditation state. During meditation, I feel some kind of a sensation I could not explain. I feel the rain dropping on my face and sometimes my legs. I feel the breeze of a tropical weather as if I was in the forest. I always sleep for a very short time at night and I have a very high sense of smell all my life. Using equisync I still sleep less, but am more relaxed when I wake up. During meditation, I can also smell the forest as if I am in the forest.

Participating in this program requires that you use your Holosync® soundtracks (!)—which takes some time. Though you’re free to do less (and progress more slowly), we suggest that you start with a half hour of listening each day, progressing to an hour a day. My bet is you’ll eagerly look forward to these sessions, though, rather than seeing them as a chore.
Maybe a favorite popular song, a certain piece of Classical music, a raucous dance beat, the pulse of Reggae, Indian, or African drums, or the chanting of Gregorian or Tibetan monks, but you probably know how the sound of music, drumming, or chanting is capable of transporting you into an altered and joyous state of mind and uplifting your spirits.
Brainwave entrainment can enhance physical, emotional and mental healing. As a matter of fact, medical experts make use of different frequencies to assist patients who suffer from depression, attention deficit disorders, alcoholism, autism, poor self esteem as well as drug addiction. You could also make use of brainwave frequencies to alleviate migraines and headaches.
An important objective of entrainment is to produce a dissociative state, which is a meditation-like state of deep relaxation. It is the brain/body rehabilitative benefits produced by this deep trance-like state that makes AVE so useful for so many conditions. The dissociative state can be first observed by noticing deep and diaphragmatic breathing. Hands and feet become warmer as arteries dilate. Skin color will become pinker as blood flow increases throughout the face and body. Blood flow will increase in the brain as well. The person will experience feelings of profound relaxation and contentment as beneficial neurotransmitters are released into the brain. When in this deep state, the brain/body’s regenerative repair chemicals (parasympathetic hormones) and stabilizing neurotransmitters such as serotonin, endorphins and dopamine are released, which restore good brain function. AVE contributes to this restoration by providing a stress-break, increasing cerebral blood flow and encouraging impaired neuronal firing which allows the brain to return to normal function.

Besides, Holosync® users look forward to their listening session because the experience is wonderful, and you feel so good afterwards. But still, you do have to be willing to actually use the program. If you aren’t willing—if you don’t think the incredible mental, emotional, and spiritual benefits of this program are worth the time commitment—this isn’t for you.


With each pulsed tone, the brain produces an electrical response. The effects one experiences are the creations of the brains reaction to the “tones”, what neurologists call the “cortical evoked response” (the electrical response of the top most cortical layer of the brain). The brain is a mass of neurons, each taking part in storing, retrieving and transmitting electro-chemical impulses: information, colors, images, sounds, smells and tastes. Brainwave entrainment stimulates different areas of the brain allowing for the awakening and subsequent release of various levels of stored material. It also has an effect of  quietening the mind for clearer thought and process.
With almost 100 years of research validating the effectiveness of brainwave entrainment, it’s no wonder why it’s used by thousands of people all over the world. What does the future entail in this exciting field? With the adoption of smartphones, virtual and augmented reality, and advancements in technology reducing the cost of EEG and other forms of biofeedback devices, the entrainment possibilities are endless.
First of all, thank you for a most remarkable achievement. I have tried products in the past that purported to synchronize meditation-level brain waves — usually overlain by sappy new-age music composed by non-composers — and was invariably disappointed. However, I have been using your Equisync II and Equisync III recordings for a few weeks now and the results are truly astonishing and live up to the claims on your website.
Unleash your mental power with advanced brainwave entrainment technologies from mindmachines.com.  Relaxation, meditation, sleep, accelerated learning, peak sports performance,  motivation, stress relief, behavior modification, freedom from anxiety and more are possible with the push of a button with this powerful mind entrainment technology.  By altering brainwave your brainwave frequencies using frequency controlled patterns of light and sound these and many more brainwave states can be achieved in just minutes.  Why spend years learning to meditate when you can do in instantly with this a mind machine.
The activity of neurons generate electric currents; and the synchronous action of neural ensembles in the cerebral cortex, comprising large numbers of neurons, produce macroscopic oscillations. These phenomena can be monitored and graphically documented by an electroencephalogram (EEG). The electroencephalographic representations of those oscillations are typically denoted by the term 'brainwaves' in common parlance.[4][5]
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