The review by Cahn also notes findings describing a heightened emotional state of meditators. A more complex study, conducted in 2008 by Lutz et al., focused on emotional response during meditation.[9] This investigation involved the creation of a “compassion meditation” state by novice and experienced meditators and testing the meditators response to emotionally charged sounds. fMRI results indicated heightened activity in the cingulate cortex but also in the amygdala, temporo-parietal junction, and right posterior superior temporal sulcus in response to the emotional sounds. The authors of this study believe this indicates greater sensitivity to emotional expression and positive emotion due to the neural circuitry activated.[9]
♥ I found the Binaural Beat Machine to be my #1 focus tool. I have ADD/ADHD and am too easily distracted when I really want to focus. I turn on the binaural beats using the 16b preset for focus and turn down the volume so it's just barely present to my ear. I couple it with some classical music and am able to focus on what I want for extended periods. This literally has changed my life. Thank you!!
Recently developed entrainment software has been designed to correct specific imbalances in hemispheric activity associated with undesirable mind-states. For example, people suffering with depression often have more activity in the right hemisphere, and specially designed brainwave music decreases this activity while increasing activity in the left hemisphere, reducing depression.
Hi Marko, that isn’t one of my videos you referred to, so I can’t really answer you properly as I don’t know how their track was created. For the best answer, you should really contact the video creator. There isn’t any research that I’ve seen to suggest that you could harm your health by looping a delta track. During a typical sleep cycle, your brainwave activity will usually go up and down between the delta and theta range. It may be that you won’t experience the same quality of sleep if you spend most of your time producing mainly delta activity. With my 8-hour sleep track, I fluctuate the frequency range to try and emulate a typical sleep cycle
In addition, Western culture reinforces thought and communication styles associated with the left brain hemisphere, which controls logic, language, and linear thinking in a majority of people, as opposed to the right hemisphere which controls brain centers for emotional, intuitive, creative, and non-linear thought processes. Note that a significant minority of people has the opposite hemispheric dominance than the majority of people.
One problem with researching binaural beats is that listening to them does not guarantee brain entrainment. Although a determined listener should be able to focus on the beats enough to relax and let his or her brain match the binaural beat wavelength, sometimes, and for some people, it just won’t happen.  Also, some claims, such as astral travel, are not scientifically measurable at this time, and so are unverifiable in scientific studies. However, there are several studies that suggest that a meditative state is more easily attained when listening to binaural beats, suggesting that other such states may well be acheiveable too.
If you’re operating in Alpha mode, you’ll feel very present and in the moment. You might be somewhat reactive to the world around you, but you’ll feel like you have time to process what’s going on rather than just react on instinct. This is a wonderful state to achieve when meditating or doing something that requires coordination, focus and learning.

"Spontaneous wandering of the mind is something you become more aware of and familiar with when you meditate," continues Ellingsen, who is an experienced practitioner. "This default activity of the brain is often underestimated. It probably represents a kind of mental processing that connects various experiences and emotional residues, puts them into perspective and lays them to rest."
Our state of mind, mood, energy level, motivation, and overall well-being all emerge out of the electrical energy produced by our brains. Do you want more control of your moods and thoughts every day? If so, brainwave entrainment is a method which greatly assists many people in finding greater relaxation, better moods, and less anxiety in a way similar to how music uplifts and rejuvenates us, and brainwave entrainment techniques are available embedded into musical arrangements, giving you the benefits of both modalities.
But what would be the point of generating a beat that was at the same rate as a certain brainwave frequency? First, consider that these frequency bands relate to different states of awareness. Delta is seen in deep sleep, theta in lighter stages of sleep, alpha when we are relaxed with eyes closed, and beta when we are awake and alert. Second, the main idea behind using binaural beats to help a person relax and sleep is that of entrainment. Entrainment means that a biological process is matched to some external stimulus. For example, our circadian clock is entrained to the day/night light cycle and helps the body organize physiological processes in an appropriate way over the course of the day. A repetitive sound at the frequency of a certain brainwave band could theoretically cause the brain waves to be entrained to that frequency and thus help induce the state associated with that brainwave band. This could have therapeutic utility.
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.

But we don't need any studies to tell us that different people can listen to different kinds of music and be affected. A lot of people who work out have a workout playlist on their iPod that keeps them energized. Some people listen to certain music to help them fall asleep. The Muzak company has built an industry on relaxing music that will keep people in the mood to shop. Music does affect our mood, and so we already have every reason to expect binaural beat recordings to produce the same effect. Different people may find certain binaural beats to be relaxing or energizing. But, we've never found any reliable indication that a binaural beat's connection to our brain is any deeper or more meaningful than any other music track. We do know for a reasonable certainty that specific claims made by most sellers of binaural beats are not credible, and that there is no reason to think that the effect they're claimed to produce will work for you.

But the question is: Does it have a special effect on the brain? A lot of people think so. The basic claim being made for binaural beats is "resonant entrainment". Entrainment, in physics, is when two systems which oscillate at different frequencies independently are brought together, they synchronize with one another, at whatever the combined system's resonant frequency is. Examples of entrainment occur in animals in nature; for example the chirping of crickets or the croaking of frogs. Synchronization of menstrual cycles in women is another example. Even people coming together and dancing with one another is a type of entrainment. The basic claim for binaural beats is that the perceived low-frequency beat will entrain your brain wave pattern, thus forcing your brain into some desired state.