Binaural beats or binaural tones are auditory processing artifacts, that is apparent sounds, the perception of which arises in the brain independent of physical stimuli. This effect was discovered in 1839 by Heinrich Wilhelm Dove. Binaural means involving both ears. Most evolved auditory systems feature two ears, one on either side of the head. ... This article is about compression waves. ... In psychology and the cognitive sciences, perception is the process of acquiring, interpreting, selecting, and organizing sensory information. ... In physiology, a stimulus is a detectable change in the internal or external environment. ... Heinrich Wilhelm Dove (October 6, 1803 – April 4, 1879) was a Prussian physicist and meteorologist. ...

In nature, two sounds that are similar but slightly shifted in frequency will beat to produce two new frequencies which are the average and the difference of the original two sounds. For example, a 400 Hz tone and a 410 Hz tone will form a ~405 Hz tone pulsating 10 times per second. For other uses, see Frequency (disambiguation). ... In acoustics, a beat is an interference between two sounds of slightly different frequencies, perceived as periodic variations in volume whose rate is the difference between the two frequencies. ... In mathematics, an average or central tendency of a set (list) of data refers to a measure of the middle of the data set. ... 5 - 2 = 3 (verbally, five minus two equals three) An example problem Subtraction is one of the four basic arithmetic operations; it is the inverse of addition. ... This article is about the SI unit of frequency. ...

The brain produces a similar phenomenon internally, resulting in low-frequency pulsations in the loudness 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 frequency of the tones must be below about 1,000 to 1,500 hertz for the beating to be heard. The difference between the two frequencies must be small (below about 30 Hz) for the effect to occur; otherwise the two tones will be heard separately and no beat will be perceived. The horizontal axis shows frequency in Hz Loudness is the quality of a sound that is the primary psychological correlate of physical intensity. ... For other uses, see Headphones (disambiguation). ... This article is about the SI unit of frequency. ...

Interest in binaural beats can be classified into two categories. First, they are of interest to neurophysiologists investigating the sense of hearing. Second, that binaural beats may influence the brain in more subtle ways through the entrainment of brainwaves ^{[1] [2]} and can be used to produce relaxation and other health benefits. Neurophysiology is a part of physiology as a science, which is concerned with the study of the nervous system. ... Hearing (or audition) is one of the traditional five senses, and refers to the ability to detect sound. ... Brainwave synchronization is the practice of entraining ones brainwaves to a desired frequency, by means of a periodic stimulus with corresponding frequency. ... “EEG” redirects here. ...

History

Heinrich Wilhelm Dove discovered binaural beats in 1839. While research about them continued after that, the subject basically remained a scientific curiosity until 134 years later, with the publishing of Gerald Oster's article "Auditory Beats in the Brain" (Scientific American, 1973). Oster's paper was landmark not so much for its own new laboratory findings, but rather that in the way in which it identified and tied together the isolated islands of relevant research done since Dove, in a way that gave the subject fresh insight and relevance to scientific research.

In particular, Oster saw binaural beats as a powerful tool for cognitive and neurological research, addressing questions such as how animals locate sounds in their three-dimensional environment, and also the remarkable ability of animals to pick-out and focus-on specific sounds in a sea of noise (what is known as the "cocktail party effect"). The field of cognitive neuroscience concerns the scientific study of the neural mechanisms underlying cognition and is a branch of neuroscience. ... Sound localization is a listeners ability to identify the location of origin of a detected sound or the methods in acoustical engineering to simulate the placement of an auditory cue in a virtual 3D space (see binaural recording). ... The cocktail party effect describes the ability to focus ones listening attention on a single talker among a mixture of conversations and background noises, ignoring other conversations[1]. This effect reveals one of the surprising abilities of our auditory system, which enables us to talk in a noisy place. ...

Oster also considered binaural beats to be a potentially useful medical diagnostic tool, not merely for finding and assessing auditory impairments, but also (because they involved different neurological pathways than ordinary auditory processing) for more general neurological conditions. For example, Oster found that a number of the subjects he worked with that were incapable of perceiving binaural beats suffered from Parkinson's disease. In one case, Oster was able to follow one such subject through a week-long treatment of Parkinson's disease; at the outset the patient couldn't perceive binaural beats, but by the end of the week of treatment, the patient could hear them again. Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ...

Oster also reported (in corroborating an earlier study) that there were gender differences in the perception of beats. Specifically, women seemed to experience two separate peaks in their ability to perceive binaural beats that seemed to correlate with specific points in the menstrual cycle (one at the onset of menstruation, one around 15 days later), which led Oster to wonder if binaural beats could be used as a tool for measuring relative levels of estrogen. ^[1] Menstrual cycle The menstrual cycle is a recurring cycle of physiologic changes that occurs in the females of several mammals, including human beings and other apes. ... Estriol. ...

Physiology

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The sensation of binaural beats is believed to originate in the superior olivary nucleus, a part of the brain stem. They 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. ^[3] 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 synchronization states 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.^[4] Image File history File links This is a lossless scalable vector image. ... In anatomy, the olivary bodies or simply olives (Latin oliva and olivae, singular and plural, respectively) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. ... The brain stem is the lower part of the brain, adjoining and structurally continuous with the spinal cord. ...

Hypothetical effects on brain function

For more details on this topic, see brainwave synchronization.

Brainwave synchronization is the practice of entraining ones brainwaves to a desired frequency, by means of a periodic stimulus with corresponding frequency. ...

Overview

Binaural beats may influence functions of the brain besides those related to hearing. This phenomenon is called frequency following response. The concept is that if one receives a stimulus with a frequency in the range of brain waves, the predominant brain wave frequency is said to be likely to move towards the frequency of the stimulus (a process called entrainment).^[5] In addition, and very significantly, binaural beats have been credibly documented to entrain brainwave rhythms, according to the frequency following response, at various sites in the brain.^{[6] [7] [8] [9] [10]} Brainwave synchronization is the practice of entraining ones brainwaves to a desired frequency, by means of a periodic stimulus with corresponding frequency. ...

The stimulus does not have to be aural; it can also be visual^[11] or a combination of aural and visual.^[12] (One such example would be Dreamachine.) However, using alpha frequencies with such stimuli can trigger photosensitive epilepsy. homemade version semi-off The Dreamachine (or Dream Machine) was invented by Beat generation members Brion Gysin and Ian Sommerville in 1959. ... Photosensitive epilepsy is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights, bold, regular patterns, or regular moving patterns. ...

Direct use of an infrasonic auditory stimulus is impossible, since the ears cannot hear sounds low enough to be useful for brain stimulation. Human hearing is limited to the range of frequencies from 20 Hz to 20,000 Hz, while the frequencies of human brain waves are below about 40 Hz. To account for this, binaural beat frequencies must be used. Beat frequencies of 40 Hz have been produced in the brain with binaural sound and measured experimentally.^[13] Infrasound is sound with a frequency too low to be detected by the human ear. ...

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.^[14] 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.^[15][16] Interference of two circular waves - Wavelength (decreasing bottom to top) and Wave centers distance (increasing to the right). ... A delta wave is a large, slow brain wave associated with deep sleep. ... In humans, a theta wave is an electroencephalogram pattern normally produced while awake but relaxed or drowsy. ... Alpha Waves (also known as Continuum) is an early 3D game that combines labyrinthine exploration with platform gameplay. ... Beta is the frequency range of brain activity above 12 Hz (12 transitions or cycles per second). ... Gamma waves A gamma wave is a pattern of brain waves, associated with perception and consciousness. ... “EEG” redirects here. ...

Binaural beat stimulation has been used fairly extensively to induce a variety of states of consciousness, there has been some work done in regards to the effects of these stimuli on relaxation, focus, attention, and states of consciousness.^[17] Studies have shown that with repeated training to close frequency sounds that a plastic reorganization of the brain occurs for the trained frequencies^[18] and is capable of asymmetric hemispheric balancing.^[19]

Brain waves

Main article: Electroencephalography

(The precise boundaries between ranges vary among definitions, and there is no universally accepted standard.) “EEG” redirects here. ... For other uses, see Dream (disambiguation). ... For other senses of this word, see Meditation (disambiguation). ... For other uses, see Sleep (disambiguation). ...

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 little less for a waking person), and then slowly decreasing it towards the desired frequency.

Some people find pure sine waves unpleasant, so a pink noise or another background (e.g. 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 is supposed not to 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 the next paragraph). In trigonometry, an ideal sine wave is a waveform whose graph is identical to the generalized sine function y = Asin[ω(x − α)] + C, where A is the amplitude, ω is the angular frequency (2π/P where P is the wavelength), α is the phase shift, and C... Pink noise spectrum Pink noise ( ), also known as 1/f noise or flicker noise, is a signal or process with a frequency spectrum such that the power spectral density is proportional to the reciprocal of the frequency. ...

Other uses

In addition to lowering the brain frequency to relax the listener (or to raise it to help focusing), there are other controversial, alleged uses for binaural beats. For example, using specific frequencies you can stimulate certain glands to produce desired hormones. Beta-endorphin has been modulated in studies using alpha-theta brain wave training. ^[20] and dopamine with binaural beats.^[21] 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 some people find that half an hour in the theta state can reduce sleeping needs up to four hours; however, this is supposed to happen with any way to get into theta state, e.g. meditation); some use them for lucid dreaming and even for attempting out-of-body experiences, astral projection, telepathy and psychokinesis. However, most people believe that these phenomena do not exist, let alone that they can be achieved by entraining the brain to a specific frequency (with the exception of lucid dreams, that is, when the dreamer knows he is dreaming and can control the dream; this is acknowledged even by mainstream science^{[22] [23] [24]}) Alpha-theta brainwave training has also been used successfully for the treatment of addictions, ^{[20] [25] [26]} for the recovery of repressed memories, but as with other techniques this can lead to false memories. ^[27] Human submaxillary gland. ... For other uses, see Hormone (disambiguation). ... For other senses of this word, see Meditation (disambiguation). ... Lucid dreams occur during REM sleep after the person becomes conscious and aware of dreaming within the dream. ... An out-of-body experience (OBE or sometimes OOBE), is an experience that typically involves a sensation of floating outside of ones body and, in some cases, perceiving ones physical body from a place outside ones body (autoscopy). ... This article is about the paranormal concept. ... Telepathy, from the Greek τῆλε, tele, remote; and πάθεια, patheia, to be effected by, describes the hypothetical transfer of information on thoughts or feelings between individuals by means other than the five classical senses. ... The term psychokinesis (from the Greek ψυχή, psyche, meaning mind, soul, or breath; and κίνησις, kinesis, meaning motion; literally movement from the mind)[1][2] or PK, also known as telekinesis[3] (Greek + , literally distant-movement referring to telekinesis) or TK, denotes the paranormal ability of the mind to influence matter, time... Heroin bottle An addiction is a recurring compulsion by an individual to engage in some specific activity, despite harmful consequences to the individuals health, mental state or social life. ... Repressed memory is one of the most controversial subjects in the history of psychology and psychiatry. ... A false memory is a memory of an event that did not happen or is a distortion of an event, as determined by externally corroborated facts of the event. ...

A trial of Delta binaural beat technology over 60 days has shown positive effect on self-reported psychologic 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 ^[21] and has been successfully trialled to lessen hospital acute pre-operative anxiety. ^[28]

Another claimed effect for sound induced brain synchronization is enhanced learning ability. It was realised in the 70's that induced alpha brain waves enabled students to assimilate more information with greater long term retention. ^[29] In more recent times has come more understanding of the role of theta brain waves in behavioural learning ^[30] The presence of theta patterns in the brain has been associated with increased receptivity for learning and decreased filtering by the left hemisphere.^{[29] [31] [32]} 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.^[33]

Example

Binbeat Sample Image File history File links Binbeat_sample. ...

30 seconds of steady 10 Hz binaural beats with background pink noise.

Problems listening to the file? See media help. Pink noise spectrum Pink noise ( ), also known as 1/f noise or flicker noise, is a signal or process with a frequency spectrum such that the power spectral density is proportional to the reciprocal of the frequency. ...

Binbeat Sample 2 Image File history File links Binbeats2. ...

Frequency starts at 20 Hz, falls to 7.83 Hz in 10 minutes, stays constant for 15 minutes and rises back to 16 Hz in 5 minutes.

Problems listening to the file? See media help.

Direct downloads of the above files: Media:Binbeat sample.ogg Media:Binbeats2.ogg

See also

• Hemi-Sync
• Holosync
• Brainwave synchronization
• Electroencephalography
• Neurofeedback
• Mind machine
• Human enhancement
• Intelligence amplification
• Neural oscillations
• Evoked potential
• Event-related potential
• Induced activity
• Ongoing brain activity

Hemi-Sync is a trademarked brand name for a process developed at the Monroe Institute, used to create audio patterns containing binaural beats, which are commercialized in the form of audio CDs. ... Brainwave synchronization is the practice of entraining ones brainwaves to a desired frequency, by means of a periodic stimulus with corresponding frequency. ... “EEG” redirects here. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A mind machine uses ligth and sound to alter the brainwave frequency of the user. ... Human enhancement describes any attempt, whether temporary or permanent, to overcome the current limitations of human cognitive and physical abilities, whether through natural or artificial means. ... Intelligence amplification (IA) (also referred to as cognitive augmentation and machine augmented intelligence) refers to the effective use of information technology in augmenting human intelligence. ... The concept of neural oscillations is close to the concept of brain waves. ... This article does not cite its references or sources. ... An event-related potential (ERP) is any stereotyped electrophysiological response to an internal or external stimulus. ... The term induced activity is used in electroencephalography and magnetoencephalography for certain types of stimulus-related activity. ... The term Ongoing brain activity is used in electroencephalography and magnetoencephalography for those signal components that are not associated with the processing of a stimulus or the occurrence of specific other events, such as moving a body part, i. ...

References

A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 318th day of the year (319th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ...

External links

• Explanation of binaural beats using examples
• Hearing Lecture Notes (5): Binaural hearing and localization from University of Sussex
• University thesis, reveiw of literature on brainwave entrainment; Chapter 4 binaural sound Stanford
• Gnaural - GNU General Public License binaural beat generator for Win/Linux (Java version)
• SBaGen - GNU General Public License binaural beat generator for Win/Mac/Linux