Electroencephalographic Biofeedback (Neurofeedback)
Electroencephalography measures brain electric activity with the use of electodes placed on head surface.
In electroencephalographic biofeedback is employed a small portable device called electroencephalograph or encephalograph or as is worldwide known E.E.G.
The history of encephalography dates long in the past. In 1791, Galvani first noticed that nerves present some strange kind of electricity. Very small electric currents have since been named after him and are called galvanic. In 1875 the physician Richard Kayton published his treatise upon the electrical activity exhibited by the brain. He showed that brain electric currents indeed existed, some of them were produced pursuant to stimulation of the eye retina coat and acted upon the opposite brain side, this remark subsequently led to the discovery of the electroencephalograph as we currently know it.
In 1900 Adolf Beck first observed the periodically altering potential difference between two electrodes in contact with the occipital brain cortex and further noticed that these currents ceased when eyes became stimulated with light or ears with sound.
During the same period many more researches engaged in studies on the electrical activity of the brain, among them was the Russian Danilefski, who in 1876 noted that brain electrical activity presented changes, ostensibly, independent from external stimuli. In this perspective, the brain seemed to hold its own, independent electrical activity.
Polish researcher Kibulski, teacher of A. Beck, and his associates proposed an explanatory model, a mechanism regarding the plausible origin of these biological electric currents. According to Kibulski these currents were accountable to quantitative, concentration, differences of chemical substances alongside a cellular membrane. The ions flow in the nerves and muscles passed through this membrane which was semi-permeable, thus allowed only positive ions to cross it, whereas blocked negative ions. In 1914 he presented photographic data documenting brain instinctive oscillations, as he characterized them, captured from observations made on animals. However, Neminsky had a year earlier published the first photographs of brainwaves.
The first brain activity record, the very first electroencephalograph performed with electrodes on the external scalp, is attributed to Hans Berger in 1925. His primary concern was to study the basis and expression of psychic phenomena at physiological or somatic level. In 1929 he announced his classical paper on encephalography. This was a breakthrough which maximally contributed in the development of diagnostic techniques for epilepsy and brain traumatic situations in general.
The electrical activity of the brain is divided into four transmission sections, depending on the frequencies of the recorded brainwaves. These ranges are worldwide symbolized with four letters from the Greek alphabet: β, α, θ, δ.
The key features each brain activity section, or brainwave transmission range, presents are the following:
β (beta) waves: When the brain electrical activity ranges between 14-26 Hz, the encephalogram displays beta rhythm, and as is commonly said the individual is in beta state. The frequencies above 26 Hz are usually referred as high beta.
β-waves or rhythm usually correspond to brain activity connected with alertness, active thinking, active attention, focusing on the external environment or solving certain problems and also to stress related or panic inducing situations.
α (alpha) waves: When brain electrical activity ranges between 8-13 Hz, then the rhythm prevailing in the encephalogram is alpha and we say that the person is found in alpha state.
A person’s emotions while increasing his alpha rhythm have been described as general relaxation feelings, mild and pleasant, although the individual remains alert.
α-waves generally indicate the state of relaxed vigilance and also the state of non-active or passive attention, which is better described by the term spherical attention. When your brain transmits alpha waves your mind reaches a state of greater conceivability, enhancing learning processes and knowledge assimilation.
Most people produce some alpha waves when keeping their eyes closed. Thus researches were initially driven to the misconception, as was later proved, that alpha waves constitute none but waiting or scanning signals emitted from the visual centers situated in the brain. Alpha brain activity is diminished or disappears when eyes open, when hearing odd sounds, with anxiety or during intense, imperative, active mental effort.
θ (theta) waves: Theta waves range between 4-7 Hz. They appear when consciousness slips to sleeping and characterize the hypnagogic phase (falling asleep).
θ-waves have been correlated with access to the subconscious mind and unconscious material. They have also been connected to the creative esoteric inspiration and deep meditation.
δ (delta) waves: Delta waves range between 0.5-3 Hz.
δ-waves appear when the individual is in deep sleep, without dreams, the usual expression is that the person is in delta state.
J. Kamiya Langley of Porter Neuropsychiatric Institute, California Medical Center conducted pioneering researches examining control methods regarding alpha brain waves in correlation to changes of mental activity. The issue in question was whether individuals could learn to detect the production of alpha waves from their brain. He actually ascertained that after few sessions most of the individuals had improved their ability to distinguish much more than 50% of their alpha waves, a percentage indicating that the result was not accidental.
The first from a line of works on the alpha rhythm of the encephalogram and its relation to consciousness states was carried out in 1958 at Chicago University. William Dement had by that time completed at the sleep laboratory run by N.Kleitman his techniques for encephalogram recording and detection of dreams and a big discussion had opened on dreams, consciousness and the first stage of sleep.
More widely known is the encephalograph used in hospitals, which records information on paper, each line corresponding to signals received from one pair of electrodes. In these readings we can identify various waveforms, for instance, low frequency waves which are often associated with brain tumors or the typical waveforms in epileptic seizures. On the other hand, the nature of the information required in biofeedback is completely different and is associated to the way brain functions.The electroencephalograph used nowadays in modern biofeedback laboratories is connected to computers and provides us the possibility to select, in cooperation with the trainee, the way the brain waves will be displayed.
Encephalographic biofeedback is already successfully applied in a wide range of pathological conditions, among which mainly: deficit disorder attention, hyperactivity, alcoholism, toxic substances abuse, compulsory neurosis, epilepsy, post-traumatic stress, game and pre-game athletic stress, job stress etc.
Recently, enormous technological advances provided great thrust in encephalographic biofeedback progress, opening perspectives which, according to the latest results, seem to surpass all expectations.
Biofeedback encephalography is regularly used to produce θ (theta) brainwaves for the purposes of deep relaxation and expansion of intellectual and conceptual faculties. Through encephalographic biofeedback you learn to produce the brainwaves corresponding to the specific psychophysiological or mental state you long to reach. For example, in order to achieve goal focus or concentration you need to learn to enhance β waves production from a certain brain part, whereas for reaching relaxation or equinamity is required enhancement of θ waves production.
With the assistance of a program of encephalographic biofeedback, often resembling an electronic game, you learn to control brain activity, which is objectively demonstrated on your the computer screen. Many scientists call this process «brain aerobics».
In hyperactive children with deficit attention syndrome are employed encephalographic biofeedback programs similar to electronic games, in order to limit β waves while concurrently enhance θ waves, so as to increase their ability for attention and learning. J.Lubar, who has identified since 1970 encephalographic biofeedback in the treatment of attention deficit disorder hyperactivity syndrome in children, mentions: “biofeedback is capable of bringing about, in a manner different from that of medication, some of the brainwave changes which are necessary for the treatment of this syndrome. Biofeedback does not prove ancillary to children only for the purpose of producing the required brainwaves, but further enables them to normalize blood supply to brain areas which are substantially involved in addressing the problem”. An extensive program applying biofeedback techniques for the treatment of this syndrome in the USA conveyed improvement reaching up to 80%.
Encephalographic biofeedback is an indispensable tool for brain training helping you to learn how to be cured and released from your problems.
The international medical community has since 1999 accepted that at least one third of epileptic patients can considerably limit epileptic seizures with the assistance of encephalographic biofeedback. S.Othmer, one of the senior biofeedback researchers and trainer of scientists who wish to become biofeedback trainers, states: “In epileptic patients a part of the brain becomes unstable and occasionally drags along the rest part into a seizure. Encephalographic biofeedback helps in stabilizing this brain area and significanly decrease seizures”.
For many people encephalographic biofeedback, in conjunction with age delaying techniques, has become a usual ancillary practice “replenishing the energy batteries” of the organism and renewing one’s somatic and psychoemotional organ.
For numerous professionals in advertisement or arts, biofeedback provides the means for enhancing inspiration and creative work.
The basis of encephalographic biofeedback training consists in experiencing this peculiarly tranquil, detached state which is associated with αlpha brain waves. Thus, the objective is to develop your ability to reproduce the state associated with αlpha wave production, that will enabe you to enter speed reading or speed learning process.k
Without the encephalograph biofeedback resembles a computer without software.