Monday, 16 January 2012

The science of lucid dreaming - binaural beats & brain entrainment

* Brief introduction
Binaural beats or binaural tones are auditory processing artifacts (or apparent sounds), the perception of which arises in the brain for specific physical stimuli. This effect was discovered in 1839 by Prussian physicist and meteorologist, Heinrich Wilhelm Dove, and garnered greater public awareness in the late 20th century based on claims that binaural beats may help induce relaxation, meditation, creativity and other desirable mental states. The effect on the brainwaves depends on the difference in frequencies of each tone, for example, if 300 Hz was played in one ear and 310 in the other, then the binaural beat would have a frequency of 10 Hz. The brain produces a phenomenon resulting in low-frequency pulsations in the amplitude and sound localisation of a perceived sound when two tones at slightly different frequencies are presented separately - one to each of a subject's ears - using stereo headphones. A beating tone will be perceived, as if the two tones mixed naturally, out of the brain. The frequencies of the tones must be below 1,000 hertz for the beating to be noticeable. The difference between the two frequencies must be small (less than or equal to 30 Hz) for the effect to occur - otherwise, the two tones will be heard separately and no beat will be perceived by the listener. Simply put then, when signals of two different frequencies (sounds) are presented, one to each ear, the brain detects phase differences between these signals. The brain processes this anomalous information differently when these phase differences are heard with stereo headphones or speakers. A ‘perceptual integration’ of the two signals is perceived in the brain, producing the sensation of a third ‘beat’ – at the desired frequency for a particular form of brainwave entrainment. The difference between the signals waxes and wanes as the two stereo sounds mesh in and out of phase. The binaural beat is perceived as a fluctuating rhythm at the frequency of the difference between the two auditory inputs.

Binaural beats reportedly influence the brain in extremely subtle ways through the brainwave entrainment and are thought to possess therapeutic qualities – for example, it has been claimed that some binaural beats can reduce anxiety and provide other health benefits such as control over pain. Binaural beats are also of interest to neurophysiologists investigating the sense of hearing. 

The sensation of binaural beats is believed to originate in the superior olivary nucleus, a part of the brainstem and appear to be related to the brain's ability to locate the sources of sounds in three dimensions and to track moving sounds, which also involves inferior colliculus (IC) neurons. Regarding entrainment, the study of rhythmicity provides insights into the understanding of temporal information processing in the human brain - auditory rhythms rapidly entrain motor responses into stable steady synchronisation states, both below and above conscious perception thresholds. Activated regions include primary sensorimotor and cingulate areas; bilateral opercular premotor areas; bilateral SII; ventral prefrontal cortex; and, subcortically, anterior insula, putamen, and thalamus. Within the cerebellum, vermal regions and anterior hemispheres ipsilateral to the movement became significantly activated. Tracking temporal modulations additionally activated predominantly right prefrontal, anterior cingulate, and intraparietal regions as well as posterior cerebellar hemispheres. A study of aphasic subjects who had a severe stroke versus normal subjects showed that the aphasic subject could not hear the binaural beats whereas the normal subjects could. Binaural beats may influence functions of the brain in ways besides those related to hearing. This phenomenon is called ‘frequency following response’ and the concept is, that if one receives a stimulus with a frequency in the range of brainwaves, the predominant brainwave frequency is said to be likely to move towards the frequency of the stimulus (a process called ‘entrainment’). In addition, binaural beats have been credibly documented to relate to both spatial perception & stereo auditory recognition, and, according to the frequency following response, activation of various sites in the brain. The stimulus does not have to be aural; it can also be visual or a combination of aural and visual (one such example would be Dreamachine). However, using alpha frequencies with such stimuli can trigger photosensitive epilepsy in some individuals.

Perceived human hearing is limited to the range of frequencies from 20 Hz to 20,000 Hz, but the frequencies of human brainwaves are below about 40 Hz. To account for this lack of perception, binaural beat frequencies are used. Beat frequencies of 40 Hz have been produced in the brain with binaural sound and measured experimentally. When the perceived beat frequency corresponds to the delta, theta, alpha, beta, or gamma range of brainwave frequencies, the brainwaves entrain to or move towards the beat frequency. For example, if a 315 Hz sine wave is played into the right ear and a 325 Hz one into the left ear, the brain is entrained towards the beat frequency 10 Hz, in the alpha range. Since alpha range is associated with relaxation, this has a relaxing effect or if in the beta range, more alertness. An experiment with binaural sound stimulation using beat frequencies in the beta range on some participants and delta/theta range in other participants, found better vigilance performance and mood in those on the awake alert state of beta range stimulation. Binaural beat stimulation has been used fairly extensively to induce a variety of states of consciousness, and there has been some research done in regards to the effects of these stimuli on relaxation, focus, attention, and states of consciousness. Studies have shown that with repeated training to distinguish close frequency sounds that a plastic reorganisation of the brain occurs for the trained frequencies and is capable of asymmetric hemispheric balancing. 

The dominant frequency determines your current state. For example, if in someone's brain alpha waves are dominating, they are in the alpha state (this happens when one is relaxed, but awake). However, also other frequencies will be present, albeit with smaller amplitudes. The brain entraining is more effective if the entraining frequency is close to the user's starting dominant frequency. Therefore, it is suggested to start with a frequency near to one's current dominant frequency (likely to be about 20 Hz or less for a waking person), and then slowly decreasing/increasing it towards the desired frequency.

Some people find pure sine waves unpleasant, so a ‘pink noise’ or another background (i.e. natural sounds such as river noises) can also be mixed with them. In addition to that, as long as the beat is audible, increasing the volume should not necessarily improve the effectiveness, therefore using a low volume is usually suggested. One theory is to reduce the volume so low that the beating should not even be clearly audible, but this does not seem to be the case (see below).

In addition to lowering the brain frequency to relax the listener, there are other controversial, alleged uses for binaural beats. For example, that by using specific frequencies an individual can stimulate certain glands to produce desired hormones. Beta-endorphin has been modulated in studies using alpha-theta brainwave training, and dopamine with binaural beats. Among other alleged uses, there are reducing learning time and sleeping needs (theta waves are thought to improve learning, since children - who have stronger theta waves, and remain in this state for a longer period of time than adults - usually learn faster than adults; and furthermore, some people find that half an hour in the theta state can reduce sleeping needs up to 4 hours). Theta binaural beats can be used for meditation; inducement of lucid dreaming; and even for attempting out-of-body experiences, astral projection, telepathy and psychokinesis. However, the role of alpha-wave activity in lucid dreaming is subject to ongoing research. 

Alpha-theta brainwave training has also been used successfully for the treatment of addictions, and more controversially, for the recovery of repressed memories, but as with other techniques this can lead to false memories. An uncontrolled pilot study of delta binaural beat technology over 60 days has shown positive effect on self-reported psychological measures, especially anxiety. There was significant decrease in trait anxiety, an increase in quality of life, and a decrease in insulin-like growth factor-1 and dopamine and has been successfully shown to decrease mild anxiety. A randomised, controlled study concluded that binaural beat audio could lessen hospital acute pre-operative anxiety. The media has previous raised concerns regarding the psychological effect of binaural beats, comparing them to illegal narcotics. 

Gerald Oster (1973) believed binaural beats could play an important role in cognitive and neurological research – such as addressing how animals locate sounds in their three-dimensional environment and are able to pick out a specific sound in a sea of noise (the ‘cocktail party effect’). Oster also believed binaural beats were an important diagnostic tool with regard to neurological conditions, as well as auditory disorders and impairment. For example, Oster found that many of his subjects who were unable to perceive binaural beats suffered from Parkinson’s disease, although this effect could be overcome by treatment for the condition. Corroborating earlier research, Oster also examined gender differences in perception – females tend to experience two separate ‘peaks’ in their ability to perceive binaural beats, correlating with the onset of menstruation and approximately 15 days after, leading Oster to conclude that it may be possible to determine oestrogen levels using binaural beats.
Another claimed effect for sound induced brain synchronisation is enhanced learning ability. It was proposed in the 1970s that induced alpha brainwaves enabled students to assimilate more information with greater long term retention. In more recent times has come more understanding of the role of theta brainwaves in behavioural learning. The presence of theta patterns in the brain has been associated with increased receptivity for learning and decreased filtering by the left hemisphere. Based on the association between theta activity (4 – 7 Hz) and working memory performance, biofeedback training suggests that normal healthy individuals can learn to increase a specific component of their EEG activity, and that such enhanced activity may facilitate a working memory task and to a lesser extent focused attention.

There have been a number of largely unverified claims regarding binaural beats - including the suggestion that they may simulate the effect of recreational drugs; help people memorise and learn; stop smoking or other addictive behaviours; help dieting; tackle erectile dysfunction; and improve athletic performance, amongst others. However, scientific research into binaural beats is, as yet, very limited and no conclusive studies have been released to support the wilder claims listed above. However, some research indicates that binaural beats may have a relaxing effect. In absence of positive evidence for a specific effect, however, claimed effects may be attributed to the power of suggestion (the ‘placebo effect’).

The effects of binaural beats on states of consciousness were first examined by physicist Thomas Warren Campbell and Dennis Mennerich who, under the supervision of Robert Monroe (1975), sought to use binaural beat technology to induce an out-of-body experience, which eventually led to the establishment of the Monroe Institute, a charitable binaural research and education organisation, in Virginia, USA.

* Brainwaves & binaural beats
Below is a very simple diagram, outlining the 5 main brainwaves of the human brain; frequencies; and associated bodily responses. The precise boundaries between ranges vary among definitions, and there is no universally accepted standard, thus the above frequencies are approximate values.
In addition to the brainwaves outlined above, recent scientific research into binaural beats has identified two further frequencies of brainwave - lambda and epsilon waves. 

Lambda - 100 - 200 Hz
  • Newly discovered - difficult to accurately measure; little research
  • High frequency brainwaves
  • Associated with wholeness; integration; mystical experience/ out-of-body experience
  • Thought to 'ride' on low frequency epsilon frequency waves
Gamma & hyper-gamma - approx. 30 - 100 Hz
  • Generally weak in normal people, but found to be high in Tibetan monks practicing Loving Kindness meditation
  • 40 Hz is dominant frequency of gamma meditation - also the frequency the Earth's core vibrates to
  • Associated with higher awareness and mystical experience; higher mental functioning; perception; cognition; and consciousness
Beta - 13 - 39 Hz
  • Active concentration; anxiety; busy thought
  • Quick thinking and improved focus
  • Excessive time in beta state can cause stress or paranoia; muscle tension; negative moods; high blood pressure and insomnia
  • Correct balance can achieve stabilisation of moods; heightened energy levels and concentration/attentiveness
Alpha - 7 - 14 Hz
  • Conscious relaxation 
  • Variation between deep-alpha (the 'twilight' period between wake and sleep) and high-alpha (more conscious relaxation)
  • Mental absorbency; receptiveness; ideal for self-hypnosis and re-programming of the subconscious mind/accelerated learning etc
  • Eventual ability to tap into higher levels of creativity and expression
Theta - 4 - 7 Hz
  • Dreaming and changes in REM states; deep meditation
  • Dream-like stage - pre-sleep or pre-wake; meditative states
  • Sustained attention over time; enhanced creativity; boosted immune health; increased long-term memory
  • Opening the mind to new ideas/thoughts/suggestions; advanced problem-solving
  • In slower theta frequencies - increase in endorphins leading to reduction in stress; increased pain control
Delta - 0.5 - 4 Hz
  • Deep sleep and slow brain activity; deep meditative states; dreamlessness
  • Experienced for significant periods by newborn infants and healthy adults
  • Rejuvenation; restoration and healing
  • Release of anti-ageing hormones (such as HGH - human growth hormone)
  • Stress relief; strengthening of immune system health
  • Resetting of internal 'compass' 
  • In addition to inducing brainwave frequencies associated with dreaming/dream states, is it essential to get sufficient 'delta sleep' - at least 5 - 6 hours per night. As we age, the amount of 'delta sleep' we achieve nightly diminishes - one of the theories of ageing - and therefore you should actively encourage yourself to practice the induction of delta states using binaural beats if you feel you may not be getting enough deep sleep. Sometimes 'oneironauts' (dream explorers) sacrifice 'delta' or deep sleep in favour of inducing or prolonging time spent in REM states - this can have a negative effect on the restorative and healing quality of your overall sleep and is one of the reasons the Wake-Back-to-Bed (WBTB technique) of lucid dream induction is perfect. You can use a combination of binaural beats/LDS (lucid dream supplements) to induce a delta state of deep sleep for 5 - 6 hours, then wake and use your chosen methods (such as relevant binaural beats, using the guidance provided in this Blog post; and LDS associated with REM sleep states) to use the remaining segment of sleep to explore lucidity/dreaming states - without any detriment to the restive quality of your sleep.
Epsilon - < 5 Hz
  • Recently discovered; little research
  • Associated with the highest frequency brainwave - lambda
  • Also associated with the same characteristics of lambda brainwaves
  • Associated with the 'upper chakras' and the opening the 'third eye'
  • Expansion of perception and higher consciousness
Examples of brainwave frequencies in the human brain
It is estimated that only 15% of our brain activity takes places on a conscious level - meaning that the remaining 85% remains within the realms of the sub/unconscious. Credible, empirical research has yet to be conducted with regard to many functions of the unconscious mind and therefore this area of science is subject to swift change and development. Despite the pioneering work of Stephen LaBerge from the 1970s onwards, dream science is still an unchartered territory - yet with stimulated interest in the area (stemming in part from popular culture's enthusiastic response to the topic, in addition to its ancient and esteemed cross-cultural heritage) and new neuro-scientific and psychiatric studies emerging, there is some hope that academic attempts will be made to plot the unconscious mind and understand the processes and purposes of dreaming. Binaural beats are significant in unlocking how brainwaves and functioning affects levels of consciousness in humans and therefore represents a fundamental, yet underdeveloped, cornerstone of dream science.

The topic of binaural beats is a very complex one, straddling many strands of neuroscience and holistic/therapeutic health – and one I cannot do any academic justice in discussing its general theory or practical application in any greater detail here. I am only really interested in the use of binaural beats to induce changes in consciousness, and specifically, lucid dreaming.

This ‘tuning process’ involved in the use of binaural beats has an amazing effect on the mind and body - and has been scientifically proven in numerous studies, some of which have been referred to above. Within minutes of listening to binaural beats (intended for relaxation and sleep functions as opposed to those associated with stimulation, such as beta binaural beats) for the first time, you can expect:
  • Your body to feel heavy and deeply relaxed
  • Vivid visualisations, colours and patterns
  • Separation of the conscious and subconscious mind
  • Total relief from anxiety and stress
  • A feeling of sedation or total weightlessness

    * Binaural beats & lucid dreaming – my basic method
    The key to lucid dreaming is going through the delta (which causes deep, dreamless sleep – see above) then through theta states (which will cause a dream state), but instead of reaching the full alpha state (which will make you wake up), dip back into theta before you awake. Your subconscious will awake, but your conscious mind will stay asleep as you go back into the dreaming state. Your subconscious will think you are awake, but then realise you are still dreaming – thereby triggering lucidity. In other words, the binaural beat encourages deep sleep, followed by dreaming, followed by brief consciousness, then back into the dream where, if everything goes to plan, you are now very much aware of the fact you are dreaming and able to exert an influence upon your dream content. Other oneironauts suggest using theta and gamma for the induction of dream state as the latter is associated with spiritual/mystical experience and altered states of consciousness. I tend to use a theta/gamma mix, although I hope to experiment with different beats to find which ‘binaural playlist’ is most effective for a deep sleep to lucid dream experience.
    Brainwaves during the stages of sleep (above) and effect on dreaming (below)
    One (basic) method I have devised for using binaural beats for the induction of lucid dreaming is set out below. Please be aware that my method is still in inception and therefore is a work in progress and may be subject to alterations at a later stage. My approach to the practice of lucid dreaming is very trial-and-error and tailored to suit my individual needs and preferences. My documentation of my progress is intended to serve as a record of my research project, not recommendations or advice. Many sites dedicated to lucid dreaming products (i.e. binaural beats or lucid dream supplements) tend to be advertising or promoting such products in some way. I am not promoting any specific product or technique for profit or gain – any product I use in my lucid dream research has either been accessed free online; purchased from high street stores; or developed by myself as a result of my research. I might add that I have no professional scientific qualifications, simply boundless enthusiasm for the topic of dream science and general psychology/alternative health.

    All my binaural beats were found on reliable YouTube accounts and downloaded via a YouTube to MP3 converter (available free online – takes a matter of seconds per video, restricted to 20 minutes in length per item) and then transferred from my computer to an MP3 player. Using this basic method I have managed to achieve a limited degree of lucidity (one full lucid dream and lengthy, vivid dreams with short fragments of lucidity) and have been able to ‘recall’ or recognise real-life thoughts/events whilst in a dream state and question their appearance within the dream. My experimentation is still in the very early stages and needs tighter controls/implementation and recording to really ‘test’ whether the methods are actually working and which are the most effective. For example, due to an inability to recall vivid dreams experienced after taking 5-HTP as a LDS, I have discontinued using it for a period to see if my dream recall improves. Below, I have set out a way in which this problem can be overcome – a method I will be following in the next week.

    The basic method
    1. Master the MILD technique of lucid dream induction – this is, in my view, the foundation for any lucid dreaming beginner
    2. Prior to bed, take a dosage of 5-HTP supplement. This will inhibit REM sleep and encourage deep delta sleep states
    3. While falling asleep, start with a high alpha descending to low alpha. Although this is a relaxed, yet still conscious state pre-sleep/waking, you will be suggestive and receptive. Use this time to practice the MILD technique and let your mental dream conditioning ‘imprint’ itself on your brain
    4. After a period of alpha beats (as above – the timeframe is incredibly difficult to predict. I typically fall asleep within 10 minutes of getting into bed, unless I fight the urge to sleep. This is despite my consuming caffeinated drinks up until an hour before bed. My sleeping hours are usually 3 am – 11 am, as it fits around my active writing/research hours. Also factor in the possibility that 5-HTP may increase drowsiness quite quickly) – say 20 minutes – switch to a delta beat.  Set your MP3 so the beats change automatically without any actions which will disrupt your meditation. The delta beat should be of sufficient length to entrain your brain into a deep sleep mode. Therefore it is wise to have a lengthy delta sound recording which will continue playing after you have entered a deep sleep state.   My MP3 now has over an hour of delta beats following the initial alpha beats
    5. Sleep restfully
    6. Wake yourself after 6 hours of delta sleep. Use this time to use the toilet/have a drink. Due to the 6 hours of delta sleep, you should feel relaxed and rested
    7. Take a LDS associated with REM sleep; heightened dream states and improved dream recall – such as galantamine (article to follow). You will naturally experience ‘REM rebound effect’ as a result of the 5-HTP metabolising (this LDS has a half-life of approximately 6 hours, so the timing of the WBTB (Wake-Back-to-Bed) technique; ingestion of galantamine; and changes in binaural beats/brain entrainment coincides perfectly, whilst ensuring the high quality overall sleep required for good health and mental functioning)
    8. Go back to bed. Use the high to deep alpha beats and MILD technique as you feel yourself falling asleep. Use a further (approximate) 20 minutes of alpha beats for relaxation/self-suggestion (as above)
    9. Now switch to theta beats or a theta/gamma mix (I use an approximate length of 30 - 45 minutes for each ‘segment’ of theta or theta/gamma entrainment, although I hope to use longer sound recordings if my MP3 memory can handle it), interspersed with shorter periods deep-alpha, to encourage an increase in consciousness. This should hopefully induce a lucid dream state.  The periods of alpha should be sufficient to enable an increase in conscious awareness, but not enough to wake you to full consciousness. You need to be ‘conscious, yet dreaming’. Unfortunately, this is a very tricky balance to achieve and is largely overcome by experimentation over a period of time.


      1. hey i like your photos, do you have a facebook or instagram page whee i can see them?

      2. Do you mind changing background color of the webpage. It's stressful for eyes to read it with focus.

        1. Hi, I appreciate your comments, but I won't be changing the background colour of the webpage as white text on black is easiest for many people to read (studies have been done to show this) and also it is the easiest for myself to read (especially numbers, as I have dyscalculia) which is something I must take into account, as although my aim is to get as many readers as possible, I need to be able to read my own webpage and took advice from web designer and graphic designer friends when working out what background/text colour scheme is the most accessible for the greatest number and what would work best for myself. Sorry x

      3. Lots of thanks for sharing this informative post about Lucid Dreaming.It looks great. Thanks for your article and keep publishing more informative content!!