Patent No. 5365939 Method for evaluating and treating an individual with electrencephalographic disentrainment

 

Patent No. 5365939

Method for evaluating and treating an individual with electrencephalographic disentrainment feedback (Ochs, Nov 22, 1994)

Abstract

A method for treating an individual by use of electroencephalographic feedback includes selecting a reference site for determining a brain wave frequency of the individual, entraining the brain wave frequency of the individual in one direction until a first predetermined stop condition occurs, and then entraining the brain wave frequency of the individual in the opposite direction until a second predetermined stop condition occurs. A method for assessing the flexibility of an individual with respect to treatment by electroencephalographic entrainment feedback includes selecting sites for determining brain wave frequencies of the individual, choosing one of the sites which has not been previously used for entrainment, entraining the brain wave frequency of the individual at the chosen site in one direction until a first predetermined stop condition occurs, entraining the brain wave frequency of the individual at the chosen site in the opposite direction until a second predetermined stop condition occurs, and then repeating the steps beginning with choosing a site until all sites have been tested.

Notes:

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to methods and apparatus for controlling brain wave frequencies and to therapeutic uses of such methods and apparatus.

Human brains disturbed by social, mechanical, chemical or other trauma become both restricted in their electrical and chemical activity and hypersensitive to internal and external events and stimuli. In one of its aspects, the present invention pertains to the assessment and amelioration of functioning after psychological and mechanical trauma, or the enhancement of typical brain functioning, through the disruption of the restriction and rigidity of neural activity.

2. Description of Related Art

In the 1960's and early 1970's, Robert Monroe of the Monroe Institute of Applied Sciences explored the effects of sound on the brain and discovered that he could produce a driving or entrainment of brain waves. Dr. Gerald Oster, a biophysicist, also investigating the effects of sound on the brain, discovered that pulsations called binaural beats occurred in the brain when tones of different frequencies were presented separately to each ear. The beat frequency equals the frequency difference between the two tones. Both Monroe and Oster began using electronic oscillators to provide tones with frequency, purity and intensity that can be precisely controlled.

U.S. Pat. No. 3,884,218 to Robert A. Monroe shows a method for inducing sleep by amplitude modulating a pleasing sound with a delta-rhythm signal which is referred to as an "EEG sleep signal."

U.S. Pat. No. 4,191,175 to Nagle shows a method and apparatus for repetitively "producing a noise-like signal for inducing a hypnotic or anesthetic effect. . ." by creating frequency bursts of digital pulses that are then passed through a pink noise filter to get rid of frequencies above a certain cut-off. The resultant signal is then passed through a band pass filter and used to drive an audible signal source.

An apparatus for electrophysiological stimulation is shown in U.S. Pat. No. 4,227,516 to Meland et al. in which a first signal above the delta-beta frequency range is modulated by signal within that range and applied to electrodes on the forehead of a user.

A learning-relaxation device of U.S. Pat. No. 4,315,502 has both lights for pulsing signals and sound means for a pulsing sound signal as well as a control means which can individually vary the light and sound signals.

U.S. Pat. No. 4,834,701 to Masaki shows a device similar to those used by Monroe and Oster with first and second generators with frequencies above 16 hertz and a frequency difference of 4 to 16 hertz sounded to lower the brain wave frequency of a user. The term "entrainment" began to be accepted for such devices: "This phenomenon, in which one regular cycle locks into another, is now called entrainment, or mode locking." (Gleick, Chaos: Making of a New Science 1987, Penguin Books, p. 293) An article entitled "Alpha Brain Waves & Biofeedback Training" in the December 1972 Popular Electronics show a system that uses a person's own EEG signal to modulate a tone generator which, in turn, then drives a speaker heard by the same person. The device allowed a person to "hear" his or her own brain signals in an attempt to voluntarily control the frequency. A similar device that allows a person to "see" his or her own brain waves is shown in an article entitled "Mind Power: Alpha" in the July 1976 Radio-Electronics.

U.S. Pat. No. 5,036,858 to John L. Carter and Harold L. Russell shows the use of EEG electrodes attached to the head of the user along with an amplifier for determining a current brain wave frequency of a user, which is communicated to a computer processor. A new frequency is generated which is between the current brain wave frequency and a desired brain wave frequency and is within a predetermined range of the current brain wave frequency. This has become known as electroencephalographic entrainment feedback if it is used to "lock" the current brain wave frequency into a desired frequency.

Prior methods for assessment of neural function involve radiographic, magnetic, electrical and nuclear evaluations with eyes open or eyes closed states, or at best, the neuronal or other activity evoked under different conditions such as reading, drawing, doing arithmetic, etc. Static frequency stimulation, even that steady frequency stimulation which alternates from time to time, is used to assess the presence and kind of seizure activity.

Methods of treatment have in many ways attempted to ameliorate brain functioning by either providing the brain with a faithful and accurate picture of its activity, or with a means of targeting a desired frequency, range of frequencies, or relationship among frequencies, or have targeted theoretically and empirically derived frequency states as a goal of training or therapy. Methods using feedback have largely involved conscious, voluntary processes in the amelioration of neural functioning. Such methods have not fitted the stimulation frequencies to real-time measurements of neural frequency. They have taken as a goal to feedback to the brain information as to success at reaching target neural activity. These methods require conscious attention, concentration, analysis and learning.

SUMMARY OF THE INVENTION

"Disentrainment" is a term coined by the present inventor to refer to the disruption of entrained brain wave patterns, patterns which have become in some way locked. As opposed to entrainment, disentrainment is more a process that leads to the re-establishment of biological systems flexibility. As critical as the ability of a system in its ability to withstand shocks is "how well a system can function over a range of frequencies. A locking-in to a single mode can be enslavement, preventing a system from adapting to change . . . . [N]o heartbeat or respiratory rhythm can be locked into the strict periodicities of the simplest physical models, and the same is true of the subtler rhythms of the rest of the body." (Gleick, 1987, p. 293, italics author's) The EDF system according to the present invention makes more flexible a range of neurological and neurochemical systems and consequently improves conditions of patients once thought to be largely hopeless.

A method for treating an individual according to the present invention is to use electroencephalographic disentrainment feedback to "exercise" the individual's brain. One such method includes first determining a reference site for determining a brain wave frequency of the individual and placing an EEG electrode to the head of the user at that site or where the brain wave of that site may be read. Frequently, simply placing the electrode near the center of the individual's forehead gives satisfactory results which are near the dominant brain wave frequency.

A first sequence of steps is then begun, including producing a stimulation detectible by the individual with a frequency component that is a transform of the brain wave frequency. The frequency component may be at a predetermined difference from the brain wave frequency. Such a transform may include, but not be limited to, a compression, expansion, phase difference, statistical sampling or time delay from the brain wave frequency. Such a stimulation can be of the conventional sort through light goggles or earphones. A strobe light can be produced through the goggles or externally as long as it is sufficiently bright to the individual. The difference could be either plus or minus, one is simply picked to be the first polarity, determining if the entrainment is to first lead the brain wave frequency to a higher or a lower frequency.

If a first predetermined time has not elapsed from the initiation of the first sequence of steps and the brain wave frequency has not reached a first limit corresponding to the first polarity, then the first sequence of steps is repeated. If, on the other hand, the first predetermined time has elapsed or the brain wave frequency has reached the first limit, then a second sequence of steps is begun. Either the first or the second sequence of steps can be stopped upon a predetermined stop condition such as end of the session or an adverse reaction by the individual. The process is then repeated in the other direction. If the first polarity was positive, entraining the individual's brain wave frequency higher, a reasonable upper limit would be around thirty hertz or even as high as forty hertz. Once that upper limit is reached or the process is timed out in the first direction, the polarity would be changed to negative and the individual's brain wave would then be entrained downwardly to a second limit, perhaps as low as two hertz.

Some individuals exhibit extreme sensitivity to flickering or strobe type lights. In some, such lights can even induce seizures. The person administering treatment needs to remain alert to any symptoms of hypersensitivity. Certain procedures are built into a preferred process when a strobe is used. The strobe frequency is set in the normal way using the leading percentage size and polarity as set. If the individual does not exhibit signs of being photosensitive, then the first sequence of steps is repeated as before. If, on the other hand, the individual does exhibit signs of being photosensitive, and the lower and mid frequency activity slopes with respect to time are positive, then the intensity of the stimulation is reduced until the slopes are zero or negative. If the individual continues to exhibit signs of being photosensitive, and the lower and mid frequency activity slopes with respect to time continue to be positive, then the frequency excursion limits are reduced until the slopes are zero or negative. If the individual continues to exhibit signs of being photosensitive, the alternating positive and negative polarities are replaced by either positive or negative polarity without alternation, depending on whether the person is hypersensitive to lower or higher frequencies respectively. If the individual still continues to exhibit signs of being photosensitive, then treatment is stopped.

A method according to the present invention for assessing the flexibility of an individual with respect to treatment by brain wave variation involves testing several sites on the head of the individual. The first step is to select an initial site for determining a brain wave frequency of the individual. Stimulation detectible by the individual is begun with a frequency component at an initial difference from the brain wave frequency, the difference being at a first polarity as before. A sequence of steps is started by recording the brain wave frequency at the selected site. If the predetermined sites have not all been selected for the current frequency and polarity, then use a site that has not been selected and repeat the sequence of steps from the beginning. If the predetermined sites have all been selected for the current frequency and polarity, then determine if there has been a polarity change for the current frequency. If there has not been a change in polarity for the current frequency, then change the polarity and repeat the sequence of steps from the beginning. If, to the contrary, there has been a change in polarity for the current frequency, then determine if there has been a change in the difference in frequency. If there has not been a change in the difference in frequency, then increase the difference in frequency by a first predetermined amount or a first predetermined percentage, change the polarity and repeat the sequence of steps from the beginning. If there has been a change in the difference in frequency, then determine if the difference in frequency is less than a second predetermined amount or a second predetermined percentage. If the difference in frequency is not less than the second predetermined amount or the second predetermined percentage, then increase the difference in frequency by the first predetermined amount or the first predetermined percentage, change the polarity and repeat the sequence of steps from the beginning. If the difference in frequency is less than the second predetermined amount or the second predetermined percentage, then make a determination of flexibility according to predetermined criteria. Such criteria might depend on how rapidly the brain of the individual entrains or how far the maximum excursion extends for different sites.

It is an object of the method of treatment according to the present invention to modify both suboptimal and gross post-traumatic neural functioning, which in the past were modifiable only with great difficulty because they are neurologically locked.

The assessment method according to the present invention evaluates neuronal flexibility and maps it in many graphical forms and mathematically describes both the spectral characteristics and the brain sites involved in neuronally rigid dysfunction. This evaluation is conducted by introducing stimulation into the senses, which stimulation changes in known ways, results in surface electrical potentials that can be analyzed as flexibility, and maps the flexibility of the brain's ability to follow the changing stimulation. Mathematical transforms and statistical procedures permit the assessment of neuronal flexibility and inflexibility of the brain at various sites, and empirically tie these qualities to treatment plans. This assessment means introduces stimulation with a known and constantly changing frequency component. In one preferred form, the frequency of the stimulation is set by multiplexed coordination at each of twenty standard brain sites. The responses to the changing stimulation at each brain site are transformed and plotted graphically, allowing brain flexibility to be to be mapped topographically, and the frequency components to be graphed over time.

The treatment disruption involved in this method of neural feedback is brought about by either providing the brain a distorted feedback representation of its true activity, or a means of extending its flexibility and range of functioning. This method connects measurements of brain activity and, when appropriate, real-time measurements of autonomic and other physiological activity, to stimulation of the senses in a way that the measurements of brain activity define and guide the stimulation. This method as well distorts the representation of brain activity returned to it so that the stimulation returned to the brain is a transformation and function of the brain activity, which both disturbs and extends the brain activity beyond its typical pre-treatment or training excursions and functioning. This method as well examines the patterns found in the brain activity and both follows rules and formulates rules to modify the feedback so that the goals of increased flexibility and increased excursion of brain activity are enhanced, while keeping brain functioning within previously-recognized parameters of safe brain functioning. This method, as well, involves nonconscious, involuntary, subcortical process as well as cortical activity, and is very much a passive process. This method, in short, targets brain process and function.

These and other objects, advantages and features of this invention will be apparent from the following description taken with reference to the accompanying drawing, wherein is shown a preferred embodiment of the invention.

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From the foregoing it will be seen that this invention is well adapted to attain all of the ends and objectives hereinabove set forth, together with other advantages which are inherent to the apparatus.

It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the figures of the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.