| United States Patent |
5,954,630
|
|
Masaki
, et al.
|
September 21, 1999
|
FM theta-inducing audible sound, and method, device and recorded medium
to generate the same
Abstract
An audible sound of modulated wave where a very low-frequency wave of about
20 hertz or lower is superposed on an audio low-frequency wave effectively
stimulates Fm theta in human brain waves to improve attention and
concentration during mental tasks when auditorily administered. The
audible sound is also effective in stimulation of human alpha wave when
the very low-frequency wave lies within the range of about 2-10 hertz.
Such audible sound is artificially obtainable by generating an electric
signal which contains such a modulated wave, and transducing it into
audible sound wave.
| Inventors:
|
Masaki; Kazumi (Osaka, JP);
Matsuda; Osamu (Okayama, JP)
|
| Assignee:
|
Hayashibara; Ken (Okayama, JP)
|
| Appl. No.:
|
305834 |
| Filed:
|
September 14, 1994 |
Foreign Application Priority Data
| Sep 16, 1993[JP] | 5-252124 |
| Sep 24, 1993[JP] | 5-258973 |
| Sep 24, 1993[JP] | 5-258993 |
| Current U.S. Class: |
600/28 |
| Intern'l Class: |
A61M 021/00 |
| Field of Search: |
600/26-28
|
References Cited
U.S. Patent Documents
| 4141344 | Feb., 1979 | Barbara | 600/28.
|
| 4227516 | Oct., 1980 | Meland et al. | 600/28.
|
| 4335710 | Jun., 1982 | Williamson | 600/28.
|
| 5123899 | Jun., 1992 | Gall.
| |
| Foreign Patent Documents |
| 2569348 | Feb., 1986 | FR.
| |
| 4003476 | Aug., 1991 | DE | 600/28.
|
| 61-56653 | Mar., 1986 | JP.
| |
| 61-131757 | Jun., 1986 | JP.
| |
| 61-159970 | Jul., 1986 | JP.
| |
| 2124491 | Feb., 1984 | GB | 600/28.
|
Other References
Agu, M. et al., "1/f fluctuation with pleasant human sensation and its
application to household appliances." (abstract) Journal of the Institute
of Elecetrical Engineers of Japan, vol. 113, No. 1 (Jan. 1993).
Inouye, Tsuyoshi et al. "EEG Characteristics of Frontal Midline Theta
Activity." The EEG of Mental Activities pp. 136-148 (1988).
|
Primary Examiner: Lacyk; John P.
Attorney, Agent or Firm: Browdy and Neimark
Claims
We claim:
1. A method to generate Fm theta-inducing audible sound which contains a
modulated wave where a very low-frequency wave of about 20 hertz or lower
is superposed on an audio frequency wave, which comprises:
generating the audio frequency wave with a modulated wave-generating
circuitry;
generating the very low-frequency wave with the modulated wave-generating
circuitry;
amplitude-modulating the audio frequency wave with the very low-frequency
wave in the modulated wave-generating circuitry, to obtain a modulated
wave where the very low-frequency wave is superposed on the audio
frequency wave, and subjecting the modulated wave to electroacoustic
transduction.
2. The method of claim 1, wherein the frequency of said audio frequency
wave lies within the range of about 120-200 hertz.
3. The method of claim 1, wherein the frequency of said very low-frequency
wave lies within the range of about 2-10 hertz.
4. The method of claim 1, wherein the modulation degree of said modulated
wave lies within the range of about 30-100%.
5. The method of claim 1, wherein one of frequency, appearing timing,
duration and magnitude of said audible sound varies in accordance with a
1/f fluctuation.
6. The method of claim 1, wherein said audio frequency wave and very
low-frequency wave are in sine wave-form.
7. A device to generate Fm theta-inducing audible sound, comprising:
a modulated wave-generating circuitry to generate a modulated wave where a
very low-frequency wave of about 20 hertz or lower is superposed on an
audio low-frequency wave; and
an electroacoustic transducer to transduce said modulated wave into the
audible sound, said electroacoustic transducer being connected with an
output terminal of said modulated wave-generating circuitry.
8. A device to generate Fm theta-inducing audible sound, comprising:
a modulated wave-generating circuitry to generate a modulated wave where a
very low-frequency wave of about 20 hertz or lower is superposed on an
audio frequency wave; and
an electroacoustic transducer to transduce said modulated wave into the
audible sound, said electroacoustic transducer being connected with an
output terminal of said modulated wave-generating circuitry;
wherein said modulated wave-generating circuitry comprises:
a first oscillating circuitry to generate the audio frequency wave;
a second oscillating circuitry to generate the very low-frequency wave of
about 20 hertz or lower; and
a modulating circuitry to modulate said audio frequency wave with said very
low-frequency wave, said modulating circuitry having an input terminal
connected with output terminals of said first and second oscillating
circuitries.
9. The device of claim 5, wherein the frequency of said audio frequency
wave lies within the range of about 120-200 hertz.
10. The device of claim 5, wherein the frequency of said very low-frequency
wave lies within the range of about 2-10 hertz.
11. A device to generate Fm theta-inducing audible sound, comprising:
a modulated wave-generating circuitry to generate a modulated wave where a
very low-frequency wave of about 20 hertz or lower is superposed on an
audio frequency wave; and
an electroacoustic transducer to transduce said modulated wave into the
audible sound, said electroacoustic transducer being connected with an
output terminal of said modulated wave-generating circuitry;
wherein the modulation degree of said modulated wave lies within the range
of about 30-100%.
12. The device of claim 5, wherein one of frequency, appearing timing,
duration and magnitude of said audible sound varies in accordance with a
1/f fluctuation.
13. A therapeutic system to induce Fm theta, comprising:
a recording medium bearing a track of magnetically or optically recorded
modulated wave where a very low-frequency wave of 20 hertz or lower is
superposed on an audio low-frequency wave; and
means for playing back sound from said recording medium.
14. The system of claim 10, wherein the frequency of said audio frequency
wave lies within the range of about 120-200 hertz.
15. The system of claim 10, wherein the frequency of said very
low-frequency wave lies within the range of about 2-10 hertz.
16. A therapeutic system to induce Fm theta, comprising:
a recording medium bearing a track of magnetically or optically recorded
modulated wave where a very low-frequency wave of 20 hertz or lower is
superposed on an audio frequency wave; and
means for slaying back sound from said recording medium;
wherein a modulation degree of said modulated wave lies within a range of
about 30-100%.
17. The system of claim 10, wherein one of frequency, appearing timing,
duration and magnitude of said audible sound varies in accordance with a
1/f fluctuation.
18. The system of claim 10, wherein said low-frequency and very
low-frequency waves are in sine wave-form.
19. The system of claim 10, which is a magnetic tape or optical disk.
20. A method of increasing an amplitude of a brain wave in a subject
person, the brain wave having a baseline frequency and exhibiting 1/f
noise at the baseline frequency; the method comprising:
recording a 1/f noise sample of the 1/f noise at the baseline frequency in
a sample person;
generating an unmodulated stimulus from a high-frequency stimulus;
modulating the stimulus at the baseline frequency;
fluctuating the stimulus according to the 1/f noise sample; and
exposing the subject person to the modulated stimulus.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an audible sound which is able to induce Fm theta
in human brain waves, as well as to a method, device and recorded medium
to generate the same.
2. Description of the Prior Art
Potential differences observed two different sites in the cerebral cortex
and scalp are called as "brain waves" which have characteristic waveforms
and rhythms correspondently to mental and physical conditions. Brain waves
are usually classified into four types, i.e. "alpha wave", "beta wave",
theta wave and "delta wave" based on their frequencies. Among these, alpha
wave, which usually lies in the frequency range of 8-13 hertz, strongly,
extensively and continuously appears as mind and body relax. While beta
wave, which usually lies in the frequency range of 18-30 hertz, strongly
and extensively appears as mind and body contract. Theta and delta waves,
which are 4-8 hertz or less than 4 hertz respectively, are relevant to
hypnosis and sleep: It is said that theta wave strongly appears in
hypnagogic stage, while delta wave in turn becomes predominant as sleep
becomes deeper. As seen in Inoeu et al., The EEG of Mental Activities,
pp.136-148 (1988), certain theta wave which is observed as predominant
rhythm of 6-7 hertz around the frontal midline in adult is called as "Fm
theta" and said to be closely relevant to mental tasks. One can observe Fm
theta appearing around the frontal midline in persons who are in mental
tasks, and its magnitude and distribution become strong and extensive as
the persons' attention and concentration increase.
Since as described above Fm theta is closely connected with attention and
concentration, if Fm theta is artificially induced in workers, then it is
expected to improve their attention and concentration as well as to
improve efficiency and accuracy of tasks. There have been however
available no devices and processes which can be used to artificially
induce Fm theta.
SUMMARY OF THE INVENTION
In view of the foregoing, one object of this invention is to provide an
audible sound which enables artificial induction of Fm theta in human when
auditorily administered.
Another object of this invention is to provide a method which enables
artificial generation of such audible sound.
Further object of this invention is to provide a device which enables
artificial generation of such audible sound.
Still further object of this invention is to provide a recorded medium
which reproduceablly records such audible sound.
The present inventors studied various means which might solve these
objects, leading to the finding that Fm theta much more strongly and
extensively appeared in human when administered via the auditory sense
with an audible sound containing a modulated wave where a very
low-frequency wave of about 20 hertz or lower was superposed on an audio
low-frequency wave. The present inventors further studied various methods
and devices which might enable artificial generation of such audible
sound, leading to the finding that it was easily obtainable by
amplitude-modulating an audio low-frequency with a very low-frequency wave
of about 20 hertz or lower, and subjecting to electroacoustic transduction
the obtained electric signal which contained a modulated wave where the
very low-frequency wave was superposed on the audio low-frequency wave.
Based on these novel findings, this invention provides an Fm theta-inducing
audible sound which contains a modulated wave where a very low-frequency
wave of about 20 hertz or lower is superposed on an audio low-frequency
wave.
This invention also provides a method to generate such audible sound, which
comprises amplitude-modulating an audio low-frequency with a very
low-frequency wave of about 20 hertz or lower, and subjecting to
electroacoustic transduction the obtained electric signal which contains a
modulated wave where very low-frequency wave is superposed on the audio
low-frequency wave.
Further this invention provides a device to induce Fm theta, which
comprises a modulated wave-generating circuitry to generate a modulated
wave where a very low-frequency wave of about 20 hertz or lower is
superposed on an audio low-frequency wave, and an electroacoustic
transducer to transduce said modulated wave into an audible sound, said
electroacoustic transducer being connected with an output terminal of said
modulated wave-generating circuitry.
Still further this invention provides a recorded medium to induce Fm theta,
which bears a track of magnetically or optically recorded modulated wave
where a very low-frequency wave of about 20 hertz or lower is superposed
on an audio low-frequency wave, said recorded medium giving an audible
sound containing said modulated wave when reproduced.
The audible sound of this invention stimulates the appearance of Fm theta
in human brain waves when auditorily administered. In particular the
audible sound also stimulates the appearance of alpha wave when the very
low-frequency lies within the range of about 2-10 hertz.
The method and device of this invention are to artificially generate such
audible sound: Amplitude modulation of an audio low-frequency wave by a
very low-frequency wave of about 20 hertz or lower gives an electric
signal containing a modulated wave where the very low-frequency wave is
superposed on the audio low-frequency wave. Electroacoustic transduction
of this electric signal gives an audible sound which contains the above
mentioned modulated wave. The recorded medium of this invention gives an
audible sound which contains a modulated wave where a very low-frequency
wave is superposed on an audio low-frequency wave when reproduced with
appropriate reproducing devices.
BRIEF EXPLANATION OF THE FIGURES
FIG. 1 is the block diagram of the electric constitutive part in an Fm
theta-inducing device which generates the audible sound of this invention.
FIG. 2 illustrates the waveform of an audible sound which is given with the
Fm theta-inducing recorded media in Examples 1 and 4.
FIG. 3 is the block diagram of the electric constitutive part in an Fm
theta-inducing device which generates the audible sound of this invention.
FIG. 4 is the block diagram of an electric system which is to record in a
magnetic recording medium the modulated wave of this invention.
FIG. 5 is a topograph of Fm theta observed in subjects who were in mental
task without listening to audible sound stimuli.
FIG. 6 is a topograph of Fm theta observed in subjects who were in mental
task with listening to the audible sound of this invention.
FIG. 7 is a topograph of alpha wave observed in subjects who were sitting
with closed eyes without listening to audible sound stimuli.
FIG. 8 is a topograph of alpha wave observed in subjects who were sitting
with closed eyes with listening to the audible sound of this invention.
In the Figures, the symbols O1 and O2 designate oscillating circuitries; A1
and A2, amplifying circuitries; M, modulating circuitry; V1 through V4,
variable resistors; S, changeover switch; C, connector; P, headphone; FSM,
frequency-modulating circuitry; RFP; high-frequency power amplifying
circuitry; FSR, receiving circuitry; ANT1 and ANT2, antennas; reference
numeral 1, microprocessor; 2, appearing timing memory circuitry; 3,
duration memory circuitry; 4, clock oscillator; 5, interface; 6, modulated
wave-generating circuitry; 7, magnetic recording device; and 8, magnetic
tape.
DETAILED DESCRIPTION OF THE INVENTION
Now explaining this invention in detail in conjunction with several
embodiments and experiment, the wording "modulated wave" as referred to in
this invention means those where a very low-frequency wave of about 20
hertz or lower is superposed on an audio low-frequency wave. Such audio
low-frequency wave is feasible with continuous or pulsatile waves which
have an appropriate waveform and usually a frequency exceeding that of the
very low-frequency but not exceeding about 20,000 hertz. After testing
various low-frequency waves using healthy volunteers, several volunteers
appealed a decreased audibility and/or slight uncomfortableness when audio
low-frequency waves exceeded about 6,000 hertz. Actually it is preferable
to choose an audio low-frequency wave of about 50-3,000 hertz, desirably,
about 100-500 hertz, much more desirably, about 120-200 hertz while
considering both the frequency of the very low-frequency wave and
frequency characteristics of electroacoustic transducers to be used.
Similar studies on waveforms revealed that continuous waves such as sign
wave and pulsatile waves, for example, saw-tooth wave, square wave,
triangle wave and rectangular wave with a relatively long duration were
suitable. While the very low-frequency wave is feasible with continuous or
pulsatile waves of about 20 hertz or lower, usually, about 2-10 hertz
which are desirably in continuous waveform such as sign form or pulsatile
form with a relatively long duration as the audio low-frequency wave is.
To generate such a modulated wave, electric circuitries which are usually
called as "modulated wave-generating circuitry" are feasible and such an
electric circuitry comprises, for example, a first oscillating circuitry
to generate an audio low-frequency wave, a second oscillating circuitry to
generate a very low-frequency wave, and a modulating circuitry with an
input terminal connected with output terminals of the oscillating
circuitries so as to modulate the former audio low-frequency wave with the
latter very low-frequency wave. More particularly an audio low-frequency
wave which is generated in the first oscillating circuitry is
amplitude-modulated in the modulating circuitry with a very low-frequency
wave which is generated in the second oscillating circuitry, thus
obtaining electric signals which contain a modulated wave where the very
low-frequency wave is superposed on the audio low-frequency wave. There
are no limitations in circuits and circuit elements in such oscillating
and modulating circuitries as long as modulated waves appearing at an
output terminal of the modulating circuitry fulfills the aforementioned
requirements: Usually such circuitries are constituted mainly with
transistors, field-effect transistors and/or integrated circuits. This
invention does not hinder the insertion of appropriate amplifying and/or
matching circuitry between modulating circuitry and electroacoustic
transducer when electroacoustic transducer can not be substantially driven
only with modulating circuitry as is the case that the output of
modulating circuitry is too low or that the output terminal of the
modulating circuitry is incompatible with electroacoustic transducer due
to impedance mismatch. This invention shall of course include such
embodiments and modifications.
The modulated wave thus obtained bears a waveform as such where very
low-frequency wave encloses audio low-frequency wave and the magnitude of
audio low-frequency wave periodically varies in accordance with the
frequency of very low-frequency wave. The present inventors studied
various modulated waves with different modulation degrees for both Fm
theta inducibility and side effects in healthy volunteers leading to the
finding that Fm theta of the highest level was induced without causing
substantial side effects such as uncomfortableness when modulation degree
was in the range of about 30-100%, desirably, about 60-90%. Since the most
efficacious modulation degree and frequencies of audio low-frequency and
very low-frequency waves usually vary dependently on particular subjects,
it is desirable to provide in modulated wave-generating circuitry a
function of changing their modulation degree and/or oscillating
frequencies within the prescribed ranges so that particular subjects can
receive an audible sound with the most appropriate modulation degree and
frequencies.
By the way, Fm theta inducibility of the audible sound of this invention
can be notably augmented by imparting thereto the "1/f fluctuation".
Particularly it was revealed that by allowing the appearing timing,
duration, frequency and/or magnitude of the auditory stimulus in
accordance with the 1/f fluctuation, the audible sound and 1/f fluctuation
synergetically operated and this led to an elevated Fm theta induction
which was hardly attainable with either audible sound or 1/f fluctuation.
More particularly series with the 1/f fluctuation which can be sampled
from long-term variations in biological phenomena including brain wave,
heart beat, respiration and body heat are very useful because by varying
the appearing timing, duration, frequency and/or magnitude of audible
sound in accordance with such a series, an extremely high level of Fm
theta is induced with minimum stimuli and retained over an extended time
period even after stimulation. This would be explained as follows: Series
with the 1/f fluctuation, which are sampled from long-term variations in
human biological phenomena, contain a number of important signals relevant
to the biological regulatory mechanisms including nerve mechanism and when
administered via the auditory sense, such signals very effectively act in
stimulation of Fm theta induction to enhance physiological activities of
the audible sound of this invention. To impart such fluctuation to the
audible sound of this invention, for example, a series as described above
is memorized in microcomputer and electric signals with artificial 1/f
fluctuation which are led out therefrom are supplied via interface to the
aforementioned oscillating and modulating circuitries.
The electric signal obtained as above is then supplied to an
electroacoustic transducer where the electric signal is transduced into an
audible sound which contains the modulated wave. The wording "audible
sound" as referred to in this invention means sound waves which are
perceivable by human auditory organ, therefore the wording
"electroacoustic transducer" as referred to in the above shall mean those
which transduce into a sound wave an electric signal which contains the
modulated wave. Particular electroacoustic transducers are, for example,
those of electromagnetic type such as electrodynamic loudspeaker and
electromagnetic loudspeaker, electrostatic types such as electrostatic
loudspeaker and piez-oelectric loudspeaker, and combinations thereof.
There are no limitations in operation principle, shape and size of
electroacoustic transducers and any transducers can be used in this
invention as long as subjects can perceive via their auditory organs the
modulated wave of this invention. Miniaturized headphones and earphones
are however suitable when subjects use a device to generate the audible
sound of this invention while carrying it.
Procedures feasible to supply to electroacoustic transducer a modulated
wave which has been generated in modulated wave-generating circuitry are
classified briefly into two types: One is wire type where modulated
wave-generating circuitry and electroacoustic transducer are directly
connected with cable or the like. With this type, subjects or assistants
usually operate an electric constitutive part including modulated
wave-generating circuitry at the place where the subjects actually listen
to the audible sound. The other is wireless type where an electric
constitutive part including modulated wave-generating circuitry and
another electric constitutive part including electroaccustic transducer
are separately provided and the output signal of the modulated
wave-generating circuitry is supplied to the latter electric constitutive
part via radio or optical communication. In such wireless type, assistants
usually operate the former electric constitutive part at a remote place
rather than the place where subjects actually listen to the audible sound.
Although with respect to Fm theta induction there are no substantial
differences between these two types, the latter wireless type has
additional merits that a plurality of subjects can simultaneously listen
to the audible sound with ease, as well as that they can freely move
within the area where transmission arrives.
Electric signals which contain the modulated wave obtained as above can be
reproduceably recorded in magnetic or optical media. When reproduced with
appropriate reproducing devices, such a recorded medium gives an electric
signal containing the modulated wave which can be transduced similarly as
above into the audible sound of this invention. The method of this
invention of course includes these embodiments. The wording "recorded
medium" as referred to in the above usually means magnetic media such as
magnetic tape, magnetic disk and magnetic floppy and optical medium such
as optical disk and the method to record modulated wave in such a medium
is arbitrarily chosen dependently on particular media. In case that medium
is, for example, a magnetic tape of compact cassette type, the magnetic
tape is allowed to run while keeping it in contact with magnetic head and
energizing it with an electric signal containing the modulated wave. While
in case that medium is, for example, a compact disk, an electric signal
containing modulated wave is once converted into a digital signal, then a
master disk where the digital signal is memorized in optically readable
manner is made. Thereafter a disk material such as polycarbonate is
press-molded using the master disk, thus a compact disk with a track of
recorded modulated wave is obtained. In case that medium is either of
video tape, video disk and the like which can record pictures, one can
record pictures capable of inducing Fm theta and/or alpha wave in addition
to the modulated wave of this invention.
Since the audible sound of this invention arises no substantial differences
in induced Fm theta when subjects listen to it with one ear or both ears,
both monophonic and stereophonic modes are feasible in the above described
recording. However with stereophonic mode, for example, one can record
both modulated and non-modulated low-frequency waves on different tracks
in the same medium so that subjects are permitted to usually listen to one
track which records modulated wave but, if necessary, listen to the
modulated and non-modulated low-frequency waves while stereophonically
reproducing and arbitrarily switching the tracks. Dependently on subjects,
after listening to the audible sound of this invention over an extended
time period, they may have fatigue and/or habituation to the audible sound
which are however minimized by recording and reproducing as above.
The recorded medium thus obtained gives an electric signal containing the
modulated wave of this invention when reproduced. There are no limitations
in reproducing devices as long as such electric signal can be obtained
therewith: Usually, audio and video devices for home or business use are
feasible.
Now explaining the way of administering the audible sound of this
invention, dependently on uses but generally, it is preferable to set the
audible sound in somewhat strong level at first, then gradually in lower
level. In case that administration is for improvement of attention and
concentration during metal tasks, the audible sound is arbitrarily
administered for appropriate time period before or during each mental
task. While in case that administration is for prevention or treatment of
diseases and the like, the audible sound is administered, for example, 1-7
days/week over 1 month to 1 year at a dosage of up to about 2 hours/dose
at maximum 1-3 times/day while carefully monitoring subjects' conditions.
The sound pressure of the audible sound at this time is usually set to
about 20-90 dB, desirably, about 30-80 dB dependently on uses and
subjects. The audible sound of this invention generally gives no
substantial differences in Fm theta inducibility when subject listen to it
with one ear or both ears. Dependently on subjects, the audible sound of
this invention may stimulate the appearance of Fm theta in subjects with
very short-time dose or even with no dose when they halve listened to it
over an extended time period. The audible sound of this invention is
useful as mental training means for such subjects.
Several Examples will be given hereinafter to illustrate Fm theta-inducing
devices and recorded media which are applications of the method to
generate the audible sound of this invention.
EXAMPLE 1
Fm Theta-inducing Device
FIG. 1 is a block diagram of the electric constitutive part in an Fm
theta-inducing device which generates the audible sound of this invention.
In FIG. 1 symbols O1 and O2 designate a first and second oscillating
circuitries respectively where operation amplifiers are usually used. The
first oscillating circuitry O1 is to generate a sign wave of about 150
hertz, while the second oscillating circuitry O2 is to generate a very
low-frequency sign wave of about 2-10 hertz. In the second oscillating
circuit O2 is provided a variable resistor V1 which is to change the
frequency of the very low-frequency wave within the range of about 2-10
hertz. Symbol M designates a modulating circuitry whose input terminal is
connected with output terminals of the first and second oscillating
circuitries O1 and O2 so that the low-frequency and very low-frequency
waves are subjected to amplitude modulation here to lead out at an output
terminal of the modulating circuitry M a modulated wave where the very
low-frequency wave is superposed on the low-frequency wave. A variable
resistor V2 provided in the modulating circuitry M is to change the degree
of amplitude modulation within the range of about 30-100%. The output
terminal of the first oscillating circuitry O1 is connected via a
changeover switch S to an input terminal of a first amplifying circuitry
A1, while an output terminal of the modulating circuitry M is connected
with an input terminal of a second amplifying circuitry A2 and a contact b
in the changeover switch S. To output terminals of the first and second
amplifying circuitries A1 and A2 are removably connected via a connector C
a headphone P as electroacoustic transducer. Variable resistors V3 and V3
provided at the input terminals of the pair of amplifying circuitries A1
and A2 are to optimize the magnitudes of audible sounds radiated from the
right- and left-channel loudspeaker units in the headphone P by changing
the magnitudes of input signals for the amplifying circuitries A1 and A2.
Another variable resistor V4 provided across the input terminals of the
pair of amplifying circuitries A1 and A2 is to balance audible sounds
radiated from the right- and left-channel loudspeaker units in the
headphone P by changing the magnitudes of electric signals to be supplied
to the amplifying circuitries A1 and A2.
Now explaining the operation of this Example, when the whole circuitries
are energized while keeping the changeover switch S at the position of
contact b, outputs from the first and second oscillating circuitries O1
and O2 are supplied to the modulating circuitry M. Both outputs are mixed
here for amplitude modulation and a modulated wave having a waveform as
shown in FIG. 2 is led out at the output terminal of the modulating
circuitry M. As seen in FIG. 2, in this modulated wave a sign wave of
about 2-10 hertz is superposed on another sign wave of about 150 hertz.
The output of the modulating circuitry M is then amplified in the
amplifying circuitries A1 and A2 to a level high enough to energize the
pair of loudspeaker units in the headphone P. When the changeover switch S
is turned to the position of contact a, the modulated wave is supplied
only to the second amplifying circuitry A2, while the first amplifying
circuitry A1 receives the low-frequency wave of about 150 hertz which has
been generated by the first oscillating circuitry O1. In this case, one
loudspeaker unit in the headphone P radiates an audible sound which
contains the modulated wave, while the other loudspeaker unit another
audible sound whichi contains non-modulated sign wave.
Since this Example is arranged in this way, when subjects operate it while
putting the headphone on their head, they can listen to an audible sound
which contains either a sign wave of about 150 hertz or a modulated wave
where another sign wave of about 2-10 hertz is superposed on the former
sign wave.
EXAMPLE 2
Fm Theta-inducing Device
FIG. 3 is a block diagram of the electric constitutive part in another Fm
theta-inducing device where outputs of a modulated wave-generating
circuitry are supplied to an electroacoustic transducer in wireless
manner. Symbols O1, O2, M, V1 through V4, P and C in FIG. 3 are to refer
to the same circuitries or circuit elements as used in the Example shown
in FIG. 1 and these circuitries and circuit elements are used with the
same purpose or to achieve substantially the same functions.
As shown in FIG. 3, this Example consists of transmitting and receiving
systems. In the transmitting system a modulated wave and a sign wave which
have been generated in first and second oscillating circuitries O1 and O2
and a modulating circuitry M are supplied similarly as in the previous
Example to an input terminal of a stereophonic frequency-modulating
circuitry FSM via a changeover switch S. The frequency-modulating
circuitry FSM usually comprises a low-frequency amplifying circuitry to
amplify the modulated and sign waves applied to the aforementioned input
terminal, and a frequency-modulating circuitry having an input terminal
connected with an output terminal of the low-frequency amplifying
circuitry to convert the aforementioned modulated and sign waves into
frequency-modulated high-frequency waves. To an output terminal of the
frequency-modulating circuitry FSM is connected an input terminal of a
high-frequency power amplifying circuitry RFP to amplify the above
high-frequency waves, while an output terminal of the high-frequency power
amplifying circuitry RFP is connected with an antenna ANT1 which is to
radiate high-frequency waves. While the receiving system comprises an
antenna ANT2 to receive high-frequency waves, a stereophonic receiving
circuitry FSR to decode high-frequency voltages from the antenna ANT2 into
the original modulated and sign waves, and a headphone P as
electroacoustic transducer to convert outputs of the receiving circuitry
FSR into audible sounds.
Now explaining the operation of this Example, since this Example is
arranged in this way, when the transmitting and receiving systems are
simultaneously operated, respective loudspeaker units in the headphone P
radiate audible sounds which contain either a sign wave of about 150 hertz
or a modulated wave wherein another sign wave of about 2-10 hertz is
superposed on the former sign wave.
Because of this arrangement, by providing one or more receiving systems
against one transmitting system, allowing particular subjects to carry one
receiving system and further allowing them to arbitrarily operate ownm
receiving systems while putting on its headphone to their head, they can
listen to the audible sound of this invention. This Example is suitable to
allow a plurality of subjects to listen to the audible sound in a relative
large space at the same time.
EXAMPLE 3
Fm Theta-inducing Recorded Medium
This Example illustrates a magnetic recorded medium which gives an audible
sound whose appearing timing and duration vary in accordance with the 1/f
fluctuation when reproduced.
Now explaining along with FIG. 4 an electric circuitry to generate a
modulated wave which gives such audible sound, in the Figure, reference
numeral 1 designates a microprocessor to which an appearing timing memory
circuitry 2, a duration memory circuitry 3 and a clock oscillator 4 are
connected to form a microcomputer. Separately 25 types of time series with
the 1/f fluctuation which have been sampled from Fm theta in 5 healthy
volunteers in twenties, 3 men and 2 women, are geometrically divided into
5 steps within 0-20 times/minute for appearing timing and also into 6
steps within 0-60 seconds for duration, both of which are then memorized
in the appearing timing memory circuitry 2 and duration memory circuitry
3. The microprocessor 1 is set such that it controls clock pulses to
generate a series of pulses which correspond to the appearing timing and
duration series. Since the microprocessor 1 has a limited memorizing
capacity, it repeatedly returns to the starting data after referring to
prescribed numbers of data in the appearing timing and duration series.
The prescribed number of artificial irregular signals thus obtained are
then processed by an interface 5 into control signals with the 1/f
fluctuation for a modulated wave-generating circuitry 6. The modulated
wave-generating circuitry 6 comprises a first oscillating circuitry to
generate a sign wave of about 150 hertz, a second oscillating circuitry to
generate a sign wave of about 8 hertz, and a modulating circuitry with an
input terminal connected with output terminals of the first and second
oscillating circuitries so as to modulate the former sign wave with the
latter sign wave, and the control signals from the interface 5 are applied
to the modulating circuit in the modulating wave-generating circuitry 6 to
control its output. The output terminals of the first and second
oscillating circuitries in the modulated wave-generating circuitry 6 are
separately connected to different input terminals in a stereophonic
magnetic recording device 7.
All the circuitries were turned on with this connection and while
monitoring waveforms as appeared at the output terminal of the modulated
wave-generating circuitry 6 with oscilloscope, the modulated wave was
adjusted to a modulation degree of about 80% and at the same time a
magnetic tape 8 of compact cassette type which had been injected in the
magnetic recording device 7 was allowed to run at a rate of 4.8 cm/second,
thus recording a sign wave of about 1.50 hertz and a modulated wave where
another sign wave of about 8 hertz was superposed on the former sign wave
on different tracks in the magnetic tape 8. The magnetic tape was of
conventional type with a tape width of 3.81 m.
The recorded medium in this Example, which beared a track of magnetically
recorded sign wave of about 150 hertz and another track of magnetically
recorded modulated wave where another sign wage of about 8 hertz was
superposed on the former sign wave, gave audible sounds which contained
either the modulated wave or sign wave when reproduced. The recorded
medium in this Example is reproduceable with usual reproducing devices,
handleable and portable with ease and this permits workers to carry it
along with a reproducing device and arbitrarily listen to the audible
sound of this invention at a place where they actually do mental tasks.
The audible sound from the recorded medium in this Example has an
extremely high Fm theta inducibility because its appearing timing and
duration are both devised to vary in accordance with the 1/f fluctuation.
Although in this Example only the appearing timing and duration of the
audible sound are set variable in accordance with the 1/f fluctuation, it
is also possible to vary one of them in the same way and the other in
irregular way, as well as to vary in addition to the appearing timing and
duration the magnitude and/or frequency in either or both of the
low-frequency and very low-frequency waves within prescribed ranges in
accordance with the 1/f fluctuation. This example concretely refers only
to the use of series which is sampled from long-term variations in human
Fm theta: The present inventors tested similarly as above other series
which were sampled from long-term variations, for example, in heart beat,
blood pressure, respiration, body heat and the like, leading to results
which were slightly inferior but almost the same as in the case of Fm
theta.
EXAMPLE 4
Fm Theta-inducing Recorded Medium
Provided were a first oscillating circuitry to generate a sign wave of
about 150 hertz, a second oscillating circuitry to generate another sign
wave of about 8 hertz, a modulator with amplifying circuitry and a
stereophonic magnetic recording device which were connected as follows: An
output terminal of the first oscillating circuitry was connected to the
modulator and an output terminal in the magnetic recording device; an
output terminal of the second oscillating circuitry, to an input terminal
of the modulator; and an output terminal of the modulator, to a remaining
input terminal in the magnetic recording device. All these circuitries
were turned on and while monitoring with oscilloscope the waveform of the
modulated wave as appeared at the output terminal of the modulator, the
modulated wave was adjusted to a modulation degree of about 80%. Under
these conditions a magnetic tape of compact cassette type which had been
injected in the magnetic recording device was allowed to run at a rate of
4.8 cm/second, thus recording the modulated wave and a non-modulated
low-frequency wave, i.e. the sign wave of about 150 hertz, on different
tracks in the magnetic tape. The magnetic tape was of conventional type
wit a tape width of 3.81 mm.
The recorded medium in this Example gave audible sounds which contained
either a sign wave or a modulated wave where another sign wave of about 8
hertz was superposed on the former sign wave as shown in FIG. 2 when
reproduced. The recorded medium in this Example is reproduceable with
usual reproducing devices, handleable and portable with ease and this
permits workers to carry it along with a reproducing device and
arbitrarily listen to the audible sound of this invention at a place where
they actually do mental tasks.
EXAMPLE 5
Fm Theta-inducing Recorded Medium
This Example illustrates an optical recorded medium which gives the audible
sound of this invention when reproduced. In this Example a magnetic tape
which magnetically recorded prescribed modulated and non-modulated
low-frequency waves on different tracks was made at first, then the
magnetic tape was reproduced and the outputs were optically recorded in a
commercially-available writable optical disk with optical recording
device.
Similarly as in Example 3, a sign wave of about 150 hertz and a modulated
wave with the 1/f fluctuation from long-term variations in biological
phenomena where another sign wave of about 8 hertz was superposed on the
former sign wave were generated and then stereophonically recorded for 8
minutes on different tracks in a magnetic tape using magnetic recording
device. The magnetic tape as used was of open-reel type with a tape width
of 6.25 mm and the running rate during recording was set to 19 cm/second.
Thereafter similarly as in Example 4 a sign wave of about 150 hertz and 5
varieties of modulated waves were generated and recorded on the remaining
area in the magnetic tape while changing the frequency of the latter sign
wave in the order of 2, 10, 4, 8, 6, 7, 4 and 10 hertz after every 10
second pause and keeping respective frequencies for 1 minute. Each
modulated wave was set to a modulation degree of about 80% similarly as in
Examples 3 and 4, while recording of non-modulated sign wave in the other
track was suspended when generation of modulated waves was in pause.
The magnetic tape thus obtained was injected in a magnetic reproducing
device and its output terminal was connected via mixer to an input
terminal of conventional simplified optical recording device. Thereafter
the optical recording device was injected with an 8 inch writable optical
disk "CDM-V8" commercialized by Pioneer Electric Corporation, Tokyo, Japan
and both devices were brought into operation to record outputs of the
magnetic tape in the optical disk. The sampling frequency and quantizing
bit number during the optical recording were set to 44.1 kilohertz and 16
bits respectively, while in the optical disk several subcodes were
provided to address respective modulated waves in the former and latter
half records.
The optical recorded medium thus obtained, which beared a track of recorded
sign wave of about 150 hertz and another track of recorded modulated wave
where another sign wave of 2-10 hertz was superposed on the former sign
wave, gave audible sounds which contained either of these sign and
modulated waves when reproduced. The recorded medium in this Example is
reproduceable with usual reproducing devices, handleable and portable with
ease and this permits workers to carry it along with an reproducing device
and before or after mental tasks arbitrarily listen to the audible sound
of this invention at a place where they actually do mental tasks. Further
the recorded medium in this Example permits workers to repeatedly listen
to certain modulated waves which may be most efficacious to them because
in the recorded medium in this Example several subcodes are provided to
address respective modulated waves.
The following Experiment will concretely explain the effects of this
invention.
Experiment
Five each men and women in twenties with no psychoneurosis were chosen as
volunteers and stereophonic headphones were put on their head together
with biological electrodes in accordance with the standard electrode
arrangement recommended by the International Electroencephalogy
Association. The biological electrodes were connected with "Model 1A97A",
an electroencephalograph with data processor commercialized by NEC San-ei
Instruments, Ltd., Tokyo, Japan, while the stereophonic headphones were
connected with a magnetic reproducing device which had been injected with
a recorded medium made similarly as in Example 4 except that the range of
very low-frequency wave had been fairly extended. Thereafter the
volunteers were loaded with the Kraepelin test for 15 minutes without
receiving audible sound stimuli while detecting their brain waves which
were then amplified and recorded in a data recorder "Model XR-710"
commercialized by Teac Corporation, Tokyo, Japan. After completion of the
former half test, the volunteers were given with 5 minute rest and then
loaded with the Kraepelin test for additional 15 minutes while receiving
audible sound stimuli. During the latter half test the brain waves in the
volunteers were detected, amplified and recorded similarly as above. The
sound pressure for each audible sound stimulus was set to about 70 dB on
the volunteers' tympana.
After completion of the tests, the data in the recorder were subjected to
both 9 time add calculation and frequency analysis in a signal processor
"Model 7T18A" commercialized by NEC San-ei instruments, Ltd., Tokyo, Japan
and the Fm theta for 10 volunteers was averaged and represented in a
topograph per minute. Separately Fm theta signals which had been led out
from the F3, Fz and F4 sites in the volunteers' heads for the former 15
minute and latter 15 minute mental tasks were separately calculated into
averaged magnitudes (microvolts) per minute which were then put in the
following equation to obtain Fm theta increasing rates (%) for respective
sites. These topograph and Fm theta increasing rates were used to evaluate
each audible sound for Fm theta inducibility. The results were as shown in
Table 1 and FIGS. 5 and 6.
##EQU1##
As controls, there were provided another system (referred to as "Control 1"
hereinafter) where volunteers received no audible sound, and one another
system (referred to as "Control 2" hereinafter) where volunteers received
a non-modulated wave, i.e. a sign wave of about 150 hertz, both of which
were tested similarly as above.
TABLE 1
__________________________________________________________________________
Low-frequency
Very low-frequency
Fm theta increasing rate (%)
Progressing
wave (hertz)
wave (hertz)
F3 Fz F4 rate (%)
Remarks
__________________________________________________________________________
-- -- 100 100 100 100 Control 1
150 -- 100 101 101 100 Control 2
150 2 108 115 111 113 This invention
150 4 112 119 108 116 This invention
150 6 121 130 119 128 This invention
150 8 126 131 125 130 This invention
150 10 120 125 117 123 This invention
150 15 110 109 106 107 This invention
150 20 105 106 103 105 This invention
150 25 99 101 101 100 Control 3
150 30 97 102 100 101 Control 4
__________________________________________________________________________
As evident from the results in Table 1, although all the audible sounds
commonly contained a sign wave of about 150 hertz, there were found
significant differences in Fm theta increasing rates. In particular, when
the very low-frequency waves were about 20 hertz or lower, the Fm theta
increasing rates at all the site as tested, i.e. F3, Fz and F4, notably
increased and some of them reached to about 130% of Control 1. The
topographs in FIGS. 5 and 6 confirmed that Fm theta much more strongly and
extensively appeared around the frontal midlines of the subjects when they
were loaded with mental task while receiving the audible sound of this
invention. As seen in the results for Controls 3 and 4 in Table 1, when
very low-frequency waves were higher than 20 hertz, there were found no
significant differences in Fm theta increasing rate against Controls 1 and
2, and some subjects appealed slight uncomfortableness and decreased
concentration which were confirmed by apparent delays in progressing rates
for the Kraepelin test.
With the above experimental results, it would be understood that
efficacious very low-frequency waves were about 20 hertz or lower,
preferably, in the range of about 2-10 hertz. Similar tests where very
low-frequency wave was fixed to around 8 hertz and low-frequency wave was
arbitrarily changed in the range of about 50-6,000 hertz confirmed that Fm
theta increasing rate was significantly increased with low-frequency waves
of about 100-500 hertz and maximized at about 120-200 hertz (data not
shown). Additional tests where sign wave of about 8 hertz was superposed
on another sign wave of about 150 hertz at different modulation degrees
revealed that Fm theta increasing rate maximized at a modulation degree of
about 30-100%. Further studies where pulsatile waves such as saw-tooth
wave, square wave, triangle wave rectangular wave were replaced for sign
waves confirmed that pulsatile waves with relatively long durations marked
results which were slightly inferior but approximately comparable to those
attained with sign waves.
Separately the audible sound of this invention was further tested for
effects on appearance of alpha wave using the aforementioned 10
volunteers. In particular, a stereophonic headphone was put on the head of
each volunteer along with biological electrodes and the volunteers were
allowed to sit and relax in chair as much as possible and then receive for
60 minutes an audible sound which contained a modulated wave where a sign
wave of about 8 hertz was superposed on another sign wave of about 150
hertz. During the stimulation the brain waves in the volunteers were
detected, amplified and recorded in recorder in usual manner. After
completion of the test, the recorded data were subjected to frequency
analysis and the alpha wave of 8-10 hertz as detected for 20 minutes
immediately after starting the test was represented in topographs per
minute at 5 minute intervals. After a lapse of 3 days, the volunteers
received the same test except that audible sound was neglected. As the
result, the audible sound of this invention led to notable changes in the
subjects' alpha waves: The alpha wave without audible sound was as shown
in FIG. 7, while as seen in FIG. 8 the alpha wave became stronger and much
more extensive around the parietal sites in the subjects 15 minutes after
starting administration of the audible sound. At the same time the
appearance of beta wave was found to be notably suppressed. These
tendencies were not substantially changed even when the very low-frequency
wave was changed within the range of about 2-10 hertz.
These evidences suggest that the audible sound of this invention would have
properties of suppressing the appearance of beta wave and also stimulating
the appearance of alpha wave, as well as of stimulating the appearance of
Fm theta. Since as described above alpha and beta waves are relevant to
mental and physical relaxation and contraction respectively, the audible
sound of this invention improves attention and concentration in subjects
when they listen to it with opened eyes, while the audible sound relaxes
their mind and body when they listen to it with closed eyes.
As described above, Fm theta is a good criterion for attention and
concentration, therefore the results in this Experiment suggest that when
used in mental tasks in general, the audible sound of this invention would
improve the users' attention and concentration and keep their efficiency
and accuracy during the tasks in an elevated level. The progressing rates
(%) for the Kraepelin test also confirmed this: As seen in Table 1, the
progressing rates (%) during task were significantly enhanced when the
volunteers were loaded with it while listening to the audible sound of
this invention.
The audible sound of this invention stimulates the appearance of Fm theta
in subjects' brain waves when they listen to it. The audible sound also
stimulates the appearance of alpha wave when the very low-frequency wave
lies in the range of about 2-10 hertz. Thus the audible sound of this
invention improves and stimulates in subjects desirable states in their
mind and body, i.e. attention, concentration and relaxation, to which Fm
theta and alpha wave are relevant when they listen to it.
Because of these, the audible sound of this invention is effective in
relaxation of mind and body, improvement of creativity and efficiency in
studies and relief or elimination of reduction in thinking power,
concentration, working motivation, insomnia, fatigue, obsession, phobia
and uncompleteness, for example, due to mental diseases such as neurosis,
psychasthenia, psychosomatic disease, manic-depressive psychosis and
chronic alcohol dependence and stresses including technostresses which are
caused by electromagnetic waves from television set, video display, OA
instrument and igniter for automobiles, in addition to improvement of
attention and concentration. Thus the audible sound of this invention is
useful as means to improve efficiency, accuracy, learning ability,
researching ability and creativity in mental tasks and also to improve
concentration during playing sports at home, working place, stadium,
school, "gakushu-juku (a school for private tutoring after regular school
hours)", training place, research institution and atorie, as well as means
to prevent and treat a variety of mental diseases at working place,
clinic, hospital and sanatorium. Dependently on subjects, the audible
sound of this invention may stimulate the appearance of Fm theta with very
short-term dose or even with no dose when subjects have listened to it
over an extended time period. The audible sound of this invention is
useful as mental training means for such subjects. Further the audible
sound, which is useful as described above, is artificially and readily
obtainable by the method of this invention.
The audible sound, which is very useful as described above, is easily
obtainable by the method, device and recorded medium of this invention.
As described above, this invention would be greatly contributive to the art
and very significant.
* * * * *