Title of Invention

MAGNETIC STIMULATING CIRCUIT FOR NERVOUS CENTRALIS SYSTEM, APPARATUS, PURPOSE, AND METHOD THEREOF

Abstract The present invention relates to a magnetic stimulation apparatus for central nervous system and circuit thereof, and use of the apparatus and method of using the apparatus. The present invention, by controlling circuit design and outputting wave form signal to a drive power supply circuit, enables the drive power supply circuit to output current of corresponding wave form to coils, and by means of the design of the shape, number of turns, size, interval of the coils, generates within a certain region inside the coils a desired time-variant magnetic field which is then applied to the brain of an animal or a human being so that the central nervous system can receive a wide area synergy magnetic stimulation with a precise wave form, high frequency or a combination of a plurality of frequency components, thus achieving the treatment of nervous and psychiatric diseases or brain function improvement in combination with behavior guidance, thought guidance, or psychological guidance.
Full Text

Field of the Invention
The present invention relates to a magnetic stimulation apparatus for central
nervous system, a circuit thereof, use of the apparatus and method of using the apparatus.
Background of the Invention
Central nervous system disease or psychiatric disease is considered as the capital
killer in the 21st century since more and more people are suffering from such psychiatric
disease as depression due to their growing life pace and stress. Epidemiologic survey has
found that the prevalence, particularly lifetime prevalence, of schizophrenia and depression, is
so high that the most heavily-suffered patients even commit suicide from time to time. After
1990s, survey on the special depression-hindered group indicates a usual per thousand
prevalence of 10-20, whereas statistics published by the WHO in 2001 suggests that
psychiatric disease in our country be responsible for 20% of the total burden levied by
handicap plus illness, which is a percentage that crests the world and is still rising, and that
produces such heavy social and economic burden that it is titled the greatest disabling disease
(which deprives the patients of their ability to work and to live on their own all through their
life). Psychiatric disease, which includes schizophrenia, depression, obsessive-compulsive
disorder (OCD), attention deficit hyperactivity disorder (ADHD), post-traumatic stress
disorder (PTSD), etc., belongs to a large family of chronic encephalopathy. Recently scientists
include addictions to drugs, cyber-network and gambling, too, into psychiatric diseases.
Among the above mentioned psychiatric diseases, the most devastating and one that levies the
heaviest social and economic burden is depression, with a prevalence being 7-8% with respect
to our country's total population and 20-50% to the aged population older than 60. Current
treatment, apart from medical and psychological treatment, is primarily accomplished by
electric stimulation or magnetic stimulation both belonging to physiotherapy, wherein the
technology of magnetic stimulation, with transcranial magnetic stimulation (TMS) or
repetitive TMS (rTMS) as its major development field, is now having its application scope
expanded thanks to its characteristic of being analgesic, non-invasive and non-contacting
compared with such side effects as pain, jerk, memory deficit(MD), etc., of the electric
stimulation, as well as its other curative effects ever discovered during clinical treatment.
However, it is difficult either for the current equipment to generate effective stimulation deep
into the brain, or for cerebral cortex to receive ultra intensive stimulation which is converted
into an effective stimulation deep into the brain due to the exponential attenuation of the
magnetic induction with respect to distance. Although technology such as disclosed in CN
Application No. 96180330.4 filed on April 26, 1996, etc. is expected to meet the requirement
of focusing the magnetic stimulation in the deep, it is difficult to generate a magnetic field
with high energy while achieving a high frequency simultaneously as rTMS at present works


at a frequency of 25Hz at the most. Moreover, current magnetic stimulation apparatus
frequently applied in biomedical field usually adopts one or more round shaped coils which
are disposed in a plain and which, when used, is placed on the position to be stimulated and is
used one-sidedly, thereby limiting the research orientation to the focusing of the magnetic
stimulation and its electrophysiological sense thus introduced.
Summary of the Invention
The present invention is to overcome the deficiency of the focusing magnetic
stimulation by providing a magnetic stimulation apparatus for central nervous system for
performing magnetic stimulation on the entire brain, as well as its use in treating nervous and
psychiatric diseases and improving brain function and a methpd of controlling the magnetic
stimulation apparatus.
In order to achieve the above purpose, the present invention provides the following
technical solution: a magnetic stimulation circuit for central nervous system, including: a
control circuit, a drive power supply circuit and coils that are sequentially connected, wherein
the drive power supply circuit includes a drive circuit, a detection circuit and a main circuit,
both the drive circuit and the detection circuit are connected to the control circuit and the
main circuit respectively, and the coils are connected to the main circuit.
The main circuit may include a converting circuit for controlling currents in the
coils to flow in the same or opposite direction.
The main circuit may include at least one insulated gate bipolar transistor (IGBT)
and the control circuit generates a PWM signal which is used by the drive circuit to drive the
insulated gate bipolar transistor in the main circuit to output a time-variant current to the coils
which then generate a desired time-variant magnetic field.
The insulated gate bipolar transistor may be replaced by other full-controlled power
semiconductor devices, and the drive circuit is subject to corresponding modifications
according to technical features of the replacement devices.
The control circuit may include a Digital Signal Processing (DSP) chip functioning
as a main control chip, the drive circuit includes an optical coupler which is adapted to
transfer a control signal sent from the control circuit to the main circuit, and the control
circuit controls the drive circuit and the main circuit for the coils to generate a desired
magnetic field, and the converting circuit may include at least one relay.
Furthermore, the present invention provides a magnetic stimulation apparatus for
central nervous system, including a magnetic stimulation circuit, wherein the magnetic
stimulation circuit includes a control circuit, a drive power supply circuit and coils that are
sequentially connected, the drive power supply circuit includes a drive circuit, a detection


circuit and a main circuit, both the drive circuit and the detection circuit are connected to the
control circuit and the main circuit respectively, and the coils are connected to the main
circuit.
The coils include at least a coaxial, parallel, and symmetrically disposed
identical coil pair, with currents in the coil pair being synchronous in time and identical in
intensity and the main circuit includes a converting circuit for controlling the currents in the
coil pair to flow in the same or opposite direction.
The main circuit may include at least one insulated gate bipolar transistor (IGBT)
and the control circuit generates a PWM signal which is used by the drive circuit to drive the
insulated gate bipolar transistor in the main circuit to output a time-variant current to the coils
which then generate a desired time-variant magnetic field.
The insulated gate bipolar transistor may be replaced by other full-controlled power
semiconductor devices, and the drive circuit is subject to corresponding modifications
according to technical features of the replacement devices.
The control circuit may include a DSP chip functioning as a main control chip, the
drive circuit includes an optical coupler which is adapted to transfer a control signal sent from
the control circuit to the main circuit, and the control circuit controls the drive circuit and the
main circuit for the coils to generate a desired magnetic field, and the converting circuit may
include at least one relay.
Still further, the present invention provides use of a magnetic stimulation apparatus
for central nervous system, which involves treating central nervous system disease or
psychiatric disease or improving brain function through selecting a time-variant magnetic field
having appropriate parameters to stimulate entire brain of an animal or a human being.
The appropriate parameters include at least parameters of wave form, frequency and
peak value intensity of current relating to the coil in the apparatus, and wave form, frequency
and peak value intensity of corresponding induced magnetic field.
The appropriate parameters further include intra-train frequency and inter-train
frequency in the case of pulse train magnetic stimulation.
Curative effect of the treatment of central nervous system disease or psychiatric
disease is improved by introducing behavior guidance, thought guidance, or psychological
guidance prior to, in the middle of, or after the magnetic stimulation, the specific procedure of
which includes the following processes: magnetic stimulation having appropriate parameters
is applied to the entire brain for an appropriate period, and in the middle of or after the
magnetic stimulation, behavior guidance or thought guidance or psychological guidance is
performed on those who are receiving or those who have received the magnetic stimulation.


Optionally, those who are to receive magnetic stimulation are subject to behavior
guidance, thought guidance, or psychological guidance prior to the magnetic stimulation,
magnetic stimulation having appropriate parameters is then applied to the entire brain for an
appropriate period, and after the magnetic stimulation, those who have received the magnetic
stimulation are subject to behavior guidance, thought guidance, or psychological guidance.
The disease includes depression, anxiety disorder, insomnia, chronic pain,
post-traumatic stress disorder (PTSD), drug or alcohol dependence and addiction, psychic
dependence on abnormal behavior, attention deficit, affective or mood disorder, schizophrenia,
Parkinson's disease, neurodegenerative disease, dementia and nerve injury, etc.
The brain function includes learning and memory ability, cognitive ability, and anti
psychological stress ability.
Even further, the present invention provides a method of controlling a magnetic
stimulation apparatus for central nervous system with the apparatus being adapted to treat
central nervous system disease or psychiatric disease or improving brain function, and the
method involves electrifying coils through controlling magnetic stimulation circuit to apply a
time-variant magnetic field to an objective region, wherein magnetic induction of the magnetic
field has a gradient smaller than 100Gs/cm, and the objective region has a scope matching
head size of an animal or a human being.
The magnetic induction of the magnetic field may have a peak value smaller than
0.1T.
During the process of the magnetic stimulation, the magnetic field is of one wave
form or a combination of at least two wave forms, and the time-variant magnetic field is
within a frequency range of 0.5Hz to 2000Hz.
As can be seen from the above technical solutions, the present invention, by
controlling circuit design and outputting wave form signal to a drive power supply circuit,
enables the drive power supply circuit to output current of corresponding wave form to coils,
and by means of the design of the shape, number of turns, size, interval of the coils, generates
within a certain region inside the coils a desired time-variant magnetic field which is then
applied to the brain of an animal or a human being so that the central nervous system can
receive a wide area synergy magnetic stimulation with a precise wave form, high frequency or
a combination of a plurality of frequency components, thus achieving the treatment of nervous
and psychiatric diseases or brain function improvement in combination with behavior
guidance, thought guidance, or psychological guidance.


Brief Description of the Drawings
Figure 1 is a circuit block diagram of the apparatus according to embodiment 1 of
the present invention;
Figure 2 is a diagram of the configuration of coils according to embodiment 1 of the present
invention;
Figure 3 is a diagram of the main circuit according to embodiment 1 of the present invention;
Figure 4 is a wave form diagram adopted by embodiment 1 of the present invention;
Figure 5 is a diagram of the distribution of magnetic lines of force in the magnetic field that is
generated through electrifying coils with the currents flowing in opposite direction;
Figure 6 is a diagram of the distribution of magnetic lines of force in the magnetic field that is
generated through electrifying coils with the currents flowing in the same direction;
Figure 7 is a wave form diagram adopted by embodiment 2 of the present invention.
Detailed Description of the Embodiments
A brief introduction of the related art is now given below for a better understanding
of the technical content of the present invention:
Seen from the perspective of molecular biology, neurobiology and psychiatry, a
wide area synergy magnetic stimulation having a precise wave form, modulated frequency
(including high frequency) and a combination of a plurality of wave form/frequency
components may possess such new senses as being capable of modulating the release of
neurotransmitter and/or neuromodulator, modulating the receptor number and activity,
activating the silent synapse, facilitating the long-term potentiation (LTP) of synaptic
transmission, potentiating the synaptic plasticity, modulating the neuroendocrine. Moreover,
the synergy or causal relations of the above effects, in combination with behavior guidance,
thought guidance, or psychological guidance after the magnetic stimulation, results in a
progress of the cognitive ability and the learning and memory ability, improvement of mental
condition, treatment of nervous and psychiatric diseases. The reason is as follows:
The substance PCP that may cause schizophrenia-like symptom is found to be the
excitatory amino acid receptor (NMDA receptor) antagonist, the relation of NMDAR with
schizophrenia is attracting more and more attention. Kim (1980) was the first one to suggest
that the dopamine (DA) release increase of schizophrenia is not primary, but may be the
syndrome secondary to dysfunction of glutamatergic system. In the past 10 years, great
progress has been made in the research on the NMDA receptor and transmitter function related


with the pathogenesis of schizophrenia, particularly the research on the relation with such
deficit symptom as negative symptom, cognitive symptom, which leads to the NMDA receptor
dysfunction hypothesis on schizophrenia.
NMDA receptor, which is Magnesium-ion-blocked voltage-dependent excitatory
amino acid transmitter gate-controlled calcium ion channel receptor, is activated under the
partial depolarization condition of neuron membrane by means of cooperative effect of
glutamate and glycin (usually functioning as inhibitory neurotransmitter) to result in the
Calcium influx, thereby completing the entire process of depolarization of neuron and
initiating successive cascade reaction. NMDA holds an important seat in the research of
learning and memory cell related with molecular mechanism. In particular, LTP and the
long-term depression (LTD) are considered as the inherent mechanism of synapse modification
with the participation of NMDA receptor as its pre-requisite.
Research by Xulin et al (see Xulin, et al. Behavioural stress facilitates the induction
of long-term depression in the hippocampus. Nature(1997) 387: 497-500) indicates that stress
facilitates the hippocampus' LTD, while research by Michael T. Rogan et al (see Michael T.
Rogan, et al. Fear conditioning induces associative long-term potentiation in the amygdala.
Nature(1997) 390: 604-607) indicates that stress leads to the facilitation of amygdala's LTP.
In the hypothalamic-pituitary-adrenocortical (HPA) axis that is the main path controlling the
emotional display, hippocampus and amygdala form a negative feedback. Research by LI
Shuan-de et al (see LI Shuan-de; et al. Effect of amygdala lesion on the monoamine
transmitters in rat brain. Medical Journal of National Defending Forces In Northwest
China(2004), 25(4):257-259) indicates that the direction of neurotransmitter change is
opposite to the psychotic change after the removal of amygdala, which gives us a hint that will
the amygdala's LTP and/or hippocampus' LTD lead to the psychotic change of the
neurotransmitter release?
Many psychiatric diseases are related more or less to such life events as stress,
particularly the stressful experience during childhood or early ages, hence came out the
quality-stress hypothesis. But why is the stressful experience during early or childhood ages?
Suggested herein is a hypothesis that stressful experience of early ages forms an associative
memory (conditioned) which is widely related with the environment, and the onset of diseases
is the recall and intensification of the aversive memory. NR2A gradually replaces NR2B since
the beginning of adolescence, a period associated with the general onset age of psychiatric
diseases, which is not merely a coincidence. NR2B can produce stronger LTP than NR2A does
and the replacement of NR2B by NR2A weakens hippocampus' LTD. If this replacement
process in hippocampus and amygdala loses synchronicity or balance so that the replacement
in hippocampus anticipates that in amygdala, the negative feedback inhibitory system will also
lose balance, which leads to the onset of psychiatric diseases.


Research by Joe Z. Tsien et al (see Tang, Y. P., et al. Genetic enhancement of
learning and memory in mice. Nature(1999) 401: 63-69) indicates that NR2B may be called
"smart gene" in that mice of NR2B over-expression in their research not only possess superior
learning and memory ability, but also are faster in adapting to changes and exhibit better
extinction of aversive memory (also referred to as re-learning ability). Recently, Giovianni
Marsicano et al (see Marsicano G, et al. The endogenous cannabinoid system controls
extinction of adversive memories. Nature (2002) 418 : 530-534) has found that
endocannabinoid system is of key importance to the acceleration of the extinction of aversive
memory, while gene mutant mice of insufficient receptor CB have much slower extinction of
aversive memory than those of CB over-expression, and gene mutant mice of insufficient
receptor CB with CB agonists added have their amygdala's LTP facilitated, LTD weakened or
not generated. CB1 receptors, the natural ligand of which is still unknown, are of the greatest
amount among the G protein-coupled receptor in brain.
Neuropeptide, particularly endogenous opioid peptide (EOP), has close relationship
with emotion. Jisheng HAN et al studied the relationship between the electric stimulation with
different frequencies and the release of neuropeptide (see Han JS. Acupuncture and
endorphins. Neurosci Lett(2004). 361 (1-3):258-61) and found out that the electric
acupuncture increases the release of endogenous opioid peptide, and different frequency
causes the release of different kinds of opioid peptide to increase, which means the release of
neuropeptide is frequency dependent. They also found out (see Ji D, Sui., et al. NMDA
receptor in nucleus accumbens is implicated in morphine withdrawal in rats. Neurochem
Res(2004). 29(11):2113-20) that NMDAR agonist ketamine, if injected in nucleus accumbens,
medicates the morphine withdrawal symptom. Jisheng HAN provided in 2002 (see Han
Ji-Sheng. Induction of the release of central neuropeptides by peripheral electrical stimulation.
J Peking Univ [ Health Sci ] (2002). 34 :408-413) a systematic description about the influence
of electric stimulation to the release of neuropeptide.
Earlier research carried out by many people on the influence of magnetic stimulation
to the nerve regeneration indicates that the effect of magnetic stimulation on the nerve
regeneration is frequency dependent (see Rusovan A, et al. The stimulatory effect of magnetic
field on regeneration of the rat sciatic nerve is frequency dependent. Exp Neurol(1992).117:
81-4), while static magnetic stimulation, despite its high induction, has no effect (see Cordeiro
PG, et al.. Effect of a high-intensity static magnetic field on sciatic nerve regeneration in the
rat. Plast Reconstr Surg(1989).83(2):301-8); that magnetic field stimulation on nerve helps to
improve the activity and level of nerve growth factor (NGF) (see Longo FM, et al.
Electromagnetic fields influence NGF activity and levels following sciatic nerve transection.
J Neurosci Res(1999). 55(2):230-7) whereas Calcium ion antagonist, D600, prevents
stimulation of nerve regeneration by magnetic fields (see Rusovan A, Kanje M. D600, a Ca2+


antagonist, prevents stimulation of nerve regeneration by magnetic fields. Neuroreport(1992).
Sep.3(9):813-4); and that the electrical nerve stimulation helps to release brain derived
neurotrophic factor (BDNF) which is associated with the stimulation frequency/wave form
combination and NMDA receptor, and it is the pulse wave form with high frequency and small
interval (rectangular wave with a platform of 0.5ms and the frequency of 100Hz, and with 4
waves in a train each separated by an interval of 200ms, adding up to 75 trains or 300 pulses),
rather than the continuous lower frequency (1 Hz, 480 pulses) or higher frequency, fewer trains
with wider intervals (100Hz, and with 100 waves in a train each separated by an interval of 10s,
adding up to 3 or 6 trains), that helps to release BDNF, which is inhibited by NMDA agonist
D-AP-5 however (see Isobel J. Lever, et ah Brain-Derived Neurotrophic Factor Is Released in
the Dorsal Horn by Distinctive Patterns of Afferent Fiber Stimulation. The Journal of
Neuroscience(2001). 21(12):4469-4477). All these seem to suggest that there is a certain
association among factors such as Calcium ion, NGF, BDNF, LTP (LTD), NMDA receptor,
frequency of electric field and magnetic field, etc.
Rohan M et al (see Rohan M, et ah Low-field magnetic stimulation in bipolar
depression using an MRI-based stimulator. Am J Psychiatry(2004). 161(l):93-8) occasionally
found in the clinical research of psychiatric disease that a certain sequence in MRSI enhances
the mood of bipolar-depression patients with considerable statistical sense, base on which the
animal experiment also confirmed the effect as an antidepressant like by this magnetic
stimulation (see Carlezon WA,. et al.Antidepressant-like effects of cranial stimulation within
a low-energy magnetic field in rats. Biol Psychiatry(2005). 57:571-6).
We found that, in the experiment of forced swimming (a learned helpless animal
model usually used for screening or verifying the effects of anti-depressant), magnetic
stimulation, in combination with behavior guidance thereafter (15 minutes for the open field),
significantly improves the depressive-like behavior of model animals, while only behavior
guidance or pure magnetic stimulation exhibits no perceptible effect.
We also found that, in fear-conditioning memory extinction experiment (after the
foot shocks with acousto-optic (AO) prompt, conditioned reflex in response to the simple
acousto-optic (AO) stimulation is recorded), different parameters may lead to different results,
so as to strengthen or weaken the established fear conditioned reflex. Notice that certain
stimulation may help to intervene the memory of negative events.
The above summary and analysis give us the following two points of teaching. First,
the magnetic stimulation with a precise wave form and high frequency or a combination of a
plurality of frequency components may function as a safe stimulation means for the NMDA
receptor, and the magnetic stimulation with high frequency may, by means of NMDAR related
LTP, bring profound changes to central nervous system in multiple aspects, and affect such


process as the acquisition, extraction, modification, reinforcement of the memory to improve
relearning ability, so as to treat some nervous and psychiatric diseases under certain conditions
(such as behavior guidance after the magnetic stimulation); this inspires us to develop a wide
area synergy magnetic stimulation apparatus suitable for clinical application which can
generate a precise wave form, high frequency or a combination of a plurality of
frequency/waveform components and which can overcome the deficiency of rTMS and
electric stimulation, thus providing a new method for the treatment and prevention of nervous
and psychiatric diseases. Second, the overall research carried out on the influence of magnetic
stimulation having high frequency and a combination of a plurality of wave form/frequency
components to many aspects such as LTP, learning and memory, neurotransmitter, extinction
of memory, neuropeptide release, synaptic plasticity, etc., may bring fundamental impact to
humankind in raising intelligence, preventing psychiatric diseases and even giving up drug
addiction.
A detailed description of the present invention will be given with reference to the
specific embodiments as follows.
As shown in Figure 1, the apparatus of the present invention includes a control
circuit, a drive power supply circuit and coils, with the drive power supply circuit including a
drive circuit, a detection circuit and a main circuit, the control circuit including an upper
computer and a lower computer wherein the upper computer is a general PC or an industrial
PC so as to operate in practical applications, and connects and communicates with the lower
computer via RS232 interface to transmit command and parameters, and wherein the lower
computer adopts a Digital Signal Processing (DSP) chip as the main control chip to receive the
command and parameters from the upper computer, generate corresponding PWM signal
which is then transferred to the drive circuit, while the drive circuit and the detection circuit
are respectively connected to the lower computer and the main circuit, and the coils are
connected to the main circuit, so that the control circuit generates a PWM signal, and the drive
circuit drives the main circuit in which the insulated gate bipolar transistor (IGBT) outputs a
time variant current to stimulate the coil pair and to stimulate and generate a time variant
magnetic field. Meanwhile, the detection circuit samples the voltage and current values in the
main circuit, monitors the work status of the main circuit in real time, and adjusts the output
PWM signal if necessary, or cuts the coil circuit immediately in case of over current to prevent
the damage of coil.
The drive circuit including an optical coupler is connected between the lower
computer and the main circuit and primarily functions to shield the interference signal and
drive the main circuit. (The above described part of circuit is not shown in the drawings.)
The main circuit, as shown in Figure 3, includes a rectifier bridge BR1, five IGBTs


Q1-Q5, and two electrolytic capacitors C2 and C3 with the electrolytic capacitors C2 and C3
being connected in parallel to the output terminals of the rectifier bridge BR1. The IGBT Q1,
with its trigger terminal being connected to one pulse width modulation (PWM) terminal
PWM1 of the drive circuit, is connected between the negative terminal of electrolytic
capacitor C2 and the rectifier bridge BR1. The IGBTs Q4 and Q5, with their two trigger
terminals connected to the other two PWM1 terminals of the drive circuit (the 3 PWM1
terminals are independent), are connected in series between the negative terminal of
electrolytic capacitor C3 and the rectifier bridge BR1. The capacitors C2 and C3 are also
connected in parallel to the terminals of the other two IGBTs Q2 and Q3, with the IGBTs Q2
and Q3 having their trigger terminals respectively connected to the other two PWM terminals
PWM2 and PWM3 of the drive circuit. The coil L2 is connected between the emitter of the
IGBT Q2 and the collector of the IGBT Q3. The converting circuit includes a relay DPDT K1
with the relay Kl having its two common (input) terminals connected in parallel with both
terminals of the coil L2, and its normally open terminal on one path connected to its normally
closed terminal on the other path and its normally open terminal on the other path connected to
its normally closed terminal on the former one path. Thus, four output terminals become two
output terminals. The coil L3 is connected to the two output terminals and the coil of the relay
Kl is connected to the two controlling terminals of the lower computer. The IGBTs may be
discrete IGBT elements or an integrated IGBT module. The function of the optical coupler in
the drive circuit may also be achieved by the IGBT module integrated with driving function.
The detection circuit adopts an LEM voltage sensor and a current sensor to detect
the voltage between both terminals of capacitors C2 and C3 and the currents flowing through
two coils L2 and L3, and applies filtering, amplification and A/D conversion to the detected
signals, which are then transferred to the lower computer. (The above described part of circuit
is not shown in the drawings.)
The coils are a coaxial, parallel, and symmetrically disposed identical coil pair, the
structure of which is shown in Figure 2 with the radius supposed as R and the distance being
2a=√3R to constitute a Maxwell coil pair and to generate a linear gradient magnetic field
within the objective region between the two coils when the currents supplied flow in opposite
direction but an approximately uniform magnetic field within the objective region when the
currents supplied flow in the same direction. The objective region has a scope matching the
head size of a human being. When the coils are supplied with the currents flowing in opposite
direction, a linear gradient magnetic field is generated within a spherical region with its origin
located at point O and its radius being 0.5a, into which the human head is located as much as
possible. Additionally, the radius and the number of turns of the coil should be minimized as
much as possible, so that the hardware of the drive power supply circuit can be less
complicated and less power consumptive, which is easier to implement and makes the coil


produce less heat to adapt to the high frequency current that generates high frequency
magnetic field. An approximately uniform magnetic field can be obtained and the ergonomics
requirement can be met by giving up a little linearity of the magnetic field gradient when
setting R=180mm, which is therefore applied in a preferred embodiment. In this case, if the
coil is made to have 40 turns and the peak value of current in each turn is set to 5A, then a
magnetic field gradient of 0.5Gs/cm can be obtained in the central region. In practical
application that sets the coil to have 40 turns and the peak value of current in each turn to be
40A, a magnetic field gradient may be up to 4Gs/cm so as to achieve a satisfying curative
effect. Besides, the lower computer may control the relay K1 to convert the coil L3 from its
original connecting direction into a reverse direction so as to alter the direction of the coil
current and switch the coil currents into a flowing in the same direction, thus generating even
greater magnetic induction in the central region and improving the uniformity of magnetic
field while reducing its gradient, which, in practical application, can lead to an effect which is
different from that of the currents flowing in opposite direction.
While in operation, the user configures each parameter for system running by means
of the upper computer and the parameter is transmitted to the lower computer via serial port.
The lower computer, when receiving operating command, sends the PWM signal in the first
place to control the Q1 and Q4 of the main circuit so that voltages on capacitors C2 and C3
reach the calculated desired values, and the voltages on capacitors C2 and C3 are acquired by
the A/D converter of the lower computer via the detection circuit. When the voltages on
capacitors C2 and C3 reach the desired values, the lower computer controls the on/off of Q2,
Q3 by sending different PWM signals to them so as to generate various current wave forms,
thus generating various corresponding time-variant magnetic fields. The main circuit control
is divided into three phases, which are the rising phase, maintaining phase and dropping phase
of the current. The rising phase of the current comes first, during which Q2, Q3 are both turned
on and L2, L3 are subject to constant voltage (which is equal to the voltage on C2) so that their
currents rise linearly with the slope that may be varied by changing the voltage on C2, and the
maximum current in the coil may be varied by changing the time of this phase. Next comes the
maintaining phase, during which Q3 is still on but Q2 switches on and off intermittently so as
to maintain the current in L2, L3 in a substantially stable level. The final phase is the dropping
phase, during which Q2, Q3 are both turned off, and the currents in L2, L3 have no choice but
recharge the capacitor C3 via D2 and D3, which means that the coils L2, L3 have both of their
terminals applied a reverse voltage equal to the voltage on C3, and the currents in the coils L2,
L3 drop linearly until the values reduce to zero, with the slope that may be varied by changing
the voltage on C3. After this dropping phase followed by a zero current interval, a new rising
phase starts again, thus generating a cyclic time-variant current with a fixed period and precise
wave form, and generating a periodical time-variant magnetic field with precise wave form.


When engaged in working, the control circuit is configured and controlled to
generate the isosceles trapezium wave as shown in Figure 4, which is then applied to the coil
pair to generate the corresponding time-variant magnetic field and to induce, along the rising
edge and falling edge of the isosceles trapezium wave, an electric field with positive and
negative rectangular pulse waves within the objective region, thus meeting the medical
requirement. In an example where a rising edge of 128µs is succeeded by a platform of 768µs,
a falling edge of 128µs and a zero-current platform of 768µs which adds up to 1792µs as the
period (high frequency), the currents flow in opposite direction in the coil pair, and the peak
value of current per turn is 20A (corresponding to a magnetic field gradient of 2Gs/cm). It is
also possible to implement a combination of a plurality of wave forms and frequency
components and, by designing the number of periods for outputting and terminating the wave
form, to constitute a train of magnetic stimulation which includes such parameters as the
intra-train frequency and the inter-train frequency. For example, the above wave form is output
for 10 periods then terminated for 27 periods, which constitute a train period, so that the pulses
of the induced electric field have an intra-train frequency of 558Hz approximately (or 1116Hz
approximately if ignoring the direction of the electric field) and an inter-train frequency of
15Hz approximately (β rhythm); or. the same wave form may be terminated for 90 periods
after being stimulated for 20 consecutive periods and have an inter-train frequency of 5Hz (θ
rhythm). By means of the upper computer, users may set different magnetic stimulation
parameters in accordance with medical requirements. As the application for treating nervous
or psychiatric diseases or improving brain function, the above magnetic stimulation may be
applied to the whole brain of anyone in need of it (such as patients with depression) and kept
continuously for a suitable period. As to continuous magnetic stimulation, an uninterrupted
stimulation should not last too long each time to avoid the over activation of NMDA receptor
and the possible side effect thus introduced, whereas trains of magnetic stimulation may last
longer, such as 20 minutes. Trains of magnetic stimulation may be outputted intermittently
such as for 2 seconds, for example, in every 10 seconds and be terminated in the other 8
seconds, thus being applied periodically. For those who are receiving or have received the
magnetic stimulation, a behavior guidance, thought guidance, or psychological guidance is
carried out to complete the entire process of the treatment or brain function improvement. For
example, those who received the magnetic stimulation may experience or enter a novel
environment, or they may be inspired to think through intelligence games or problem solving,
wherein the problems may be embodied as a standard library and belong to the category of
social science or natural science or knowledge of daily life. Combinations of the problems
may be chosen in accordance with the educational background and intelligence quotient of
patients, and be solved by those who received the magnetic stimulation. Alternatively, they
may experience benign stimulation by means of specific music or image, or may keep their
brains in a benign excitement by means of psychological assistance. The behavior guidance,


thought guidance, and psychological guidance have such important feature as to give the
patients more or less puzzle while enabling them to solve successfully.
Figure 5 is a diagram of the distribution of magnetic lines of force in the magnetic
field (only half is shown) which is generated through electrifying the coils with the currents
flowing in opposite direction. As can be seen from the diagram, the magnetic lines of force
within the objective region have linear gradient distribution, with 501 being the coils, 502
magnetic lines of force, and the region within 503 the objective region into which the human
head is put during the process of treatment.
Figure 6 is a diagram of the distribution of magnetic lines of force in the magnetic
field that is generated through electrifying the coils with the currents flowing in the same
direction. As can be seen from the diagram, the magnetic lines of force within the objective
region have approximately uniform distribution, with 601 being the coils, 602 magnetic lines
of ferce and 603 the objective region into which the human head is put during the process of
treatment.
In another embodiment 2 of the present invention which has a configuration
identical to that of embodiment I, combination of another two wave forms is generated
through setting and controlling the control circuit, so that the coil pair generates corresponding
magnetic field, as shown in Figure 7 where wave A is a continuous sawtooth wave which has a
frequency of 1000Hz and lasts 3 minutes while wave B is an intermittent triangular wave
which has a frequency of 2Hz and lasts 3 minutes. These two waves occur by alternation for 3
cycles and last 18 minutes altogether to constitute a magnetic stimulation session, after which
the above behavior guidance, thought guidance, or psychological guidance is carried out to
complete the treatment of nervous and psychiatric diseases or brain function improvement.
As the use for treating nervous or psychiatric diseases or improving brain function,
the method of using the apparatus may also include carrying out behavior guidance, thought
guidance, or psychological guidance before the magnetic stimulation, wherein such guidance
before the magnetic stimulation, which may differ from that after the magnetic stimulation, is
aimed at extracting by means of the guidance the negative memory stored in the brain and
exhibiting the same, whereas guidance after the magnetic stimulation is to modify, by means
of "successful stress resistance", the negative memory and to reconstruct the negative
feedback path of the hypothalamic-pituitary-adrenocortical (HPA) axis, or improve the
antistress ability.
Apart from the above two preferred embodiments, the present invention may also
adopt a coil with oval, rectangular shape or coil with other appropriate shapes including cubic
shape, or the present invention may vary such coil parameters as the interval, number of turns,
etc., or may alternatively adopt the combination of two or more coil pairs, or a coil with larger


size, or a solenoid. The present invention may also, through controlling the control circuit and
the drive circuit, achieve the combination of more wave forms, frequencies and amplitudes to
complete a magnetic stimulation session. More wave forms of current including, for example,
isosceles trapezium, may induce a magnetic field wave form including scalene trapezium,
isosceles triangle, scalene triangle, etc. The output current may have a frequency lower than
1000Hz. A magnetic stimulation session may be completed by the combination of a plurality
of wave forms and a plurality of frequency components, or it is also possible to apply the
currents flowing in opposite direction in case of high frequency, and currents flowing in the
same direction in case of low frequency. Furthermore, the IGBTs in the main circuit may be
replaced by other full-controlled power semiconductor devices, such as the GRT, or power
MOSFET or GTO, etc., and the main circuit is modified accordingly to adapt to the technical
features of these devices, thus achieving the function of the main circuit. It is also possible to
add into the main circuit two more IGBTs or other power semiconductor devices, as well as
corresponding drive circuit and control circuit, so as to enable the currents in the coils to flow
in both directions.
Detailed description has been made hereinabove to the magnetic stimulation method
for central nervous system and its apparatus provided by the present invention in this
specification, which explains the principle and embodiments of the present invention by
means of specific examples. However, descriptions given to the above embodiments are
merely meant to help understand the method and core spirit of the present invention, while
those skilled in the art may make modifications to the embodiments and application scope
according to the principle of the present invention. Therefore, content disclosed in this
description should not be interpreted as limiting the present invention.


I CLAIM
1. A magnetic stimulation circuit for central nervous system, comprising: a control
circuit, a drive power supply circuit and coils that are sequentially connected,
wherein the drive power supply circuit comprises a drive circuit, a main circuit, and
a detection circuit for detecting the voltage and current values in the main circuit,
both the drive circuit and the detection circuit are connected to the control circuit
and the main circuit respectively, and the coils are connected to the main circuit,
wherein the main circuit comprises at least one insulated gate bipolar transistor and
the control circuit generates a PWM signal which is used by the drive circuit to drive
the insulated gate bipolar transistor in the main circuit to output a time-variant
current to the coils which then generate a desired time-variant magnetic field in an
objective region, wherein the objective region is a entire brain, magnetic induction
of the time-variant magnetic field has a peak value smaller than 0.1T, the magnetic
induction of the time-variant magnetic field has a gradient smaller than 100Gs/cm
and the time-variant magnetic field comprises intra-train frequency and inter-train
frequency.
2. The magnetic stimulation circuit for central nervous system as claimed in claim 1,
wherein the main circuit comprises a converting circuit for controlling currents in the
coils to flow in the same or opposite direction.
3. The magnetic stimulation circuit for central nervous system as claimed in claim 1,
wherein the main circuit comprises at least one full-controlled power semiconductor
device selected from a group consisting of a GRT, a power MOSFET and a GTO,
and the control circuit generates a PWM signal which is used by the drive circuit to
drive the full-controlled power semiconductor device in the main circuit to output a
time-variant current to the coils which then generate a desired time-variant
magnetic field, and the drive circuit is subject to corresponding modifications
according to technical features of the selected full-controlled power semiconductor.
4. The magnetic stimulation circuit for central nervous system as claimed in claim 2,
wherein the control circuit comprises a Digital Signal Processing (DSP) chip
functioning as a main control chip, the drive circuit comprises an optical coupler
which is adapted to transfer a control signal sent from the control circuit to the main
circuit, and the control circuit controls the drive circuit and the main circuit for the

coils to generate a desired magnetic field, and the converting circuit comprises at
least one relay.
5. A magnetic stimulation apparatus for central nervous system comprising the
magnetic stimulation circuit as claimed in claim 1, wherein the magnetic stimulation
circuit comprises a control circuit, a drive power supply circuit and coils that are
sequentially connected, wherein that the drive power supply circuit comprises a
drive circuit, a main circuit, and a detection circuit for detecting the voltage and
current values in the main circuit, both the drive circuit and the detection circuit are
connected to the control circuit and the main circuit respectively, and the coils are
connected to the main circuit, wherein the main circuit comprises at least one
insulated gate bipolar transistor and the control circuit generates a PWM signal
which is used by the drive circuit to drive the insulated gate bipolar transistor in the
main circuit to output a time-variant current to the coils which then generate a
desired time-variant magnetic field in an objective region, wherein the objective
region is a entire brain, magnetic induction of the time-variant magnetic field has a
peak value smaller than 0.1T, the magnetic induction of the time-variant magnetic
field has a gradient smaller than 100Gs/cm and the time-variant magnetic field
comprises intra-train frequency and inter-train frequency.
6. The magnetic stimulation apparatus for central nervous system as claimed in claim
5, wherein the coils comprise at least a coaxial, parallel, and symmetrically
disposed identical coil pair, with currents in the coil pair being synchronous in time
and identical in intensity, the main circuit comprises a converting circuit for
controlling the currents in the coil pair to flow in the same or opposite direction.
7. The magnetic stimulation apparatus for central nervous system as claimed in claim
5, wherein the main circuit comprises at least one full-controlled power
semiconductor device selected from a group consists of a GRT, a power MOSFET
and a GTO, and the control circuit generates a PWM signal which is used by the
drive circuit to drive the full-controlled power semiconductor device in the main
circuit to output a time-variant current to the coils which then generate a desired
time-variant magnetic field, and the drive circuit is subject to corresponding
modifications according to technical features of the selected full-controlled power
semiconductor. 10. The magnetic stimulation apparatus for central nervous system
of claim 7, wherein the control circuit comprises a DSP chip functioning as a main
control chip, the drive circuit comprises an optical coupler which is adapted to

transfer a control signal sent from the control circuit to the main circuit, and the
control circuit controls the drive circuit and the main circuit for the coils to generate
a desired magnetic field, and the converting circuit comprises at least one relay.


ABSTRACT

MAGNETIC STIMULATING CIRCUIT FOR NERVOUS CENTRALIS SYSTEM,
APPARATUS , PURPOSE, AND METHOD THEREOF
The present invention relates to a magnetic stimulation apparatus for central nervous
system and circuit thereof, and use of the apparatus and method of using the apparatus. The
present invention, by controlling circuit design and outputting wave form signal to a drive
power supply circuit, enables the drive power supply circuit to output current of corresponding
wave form to coils, and by means of the design of the shape, number of turns, size, interval of
the coils, generates within a certain region inside the coils a desired time-variant magnetic
field which is then applied to the brain of an animal or a human being so that the central
nervous system can receive a wide area synergy magnetic stimulation with a precise wave
form, high frequency or a combination of a plurality of frequency components, thus achieving
the treatment of nervous and psychiatric diseases or brain function improvement in
combination with behavior guidance, thought guidance, or psychological guidance.

Documents:

05093-kolnp-2007-abstract.pdf

05093-kolnp-2007-claims.pdf

05093-kolnp-2007-correspondence others.pdf

05093-kolnp-2007-description complete.pdf

05093-kolnp-2007-drawings.pdf

05093-kolnp-2007-form 1.pdf

05093-kolnp-2007-form 2.pdf

05093-kolnp-2007-form 3.pdf

05093-kolnp-2007-form 5.pdf

05093-kolnp-2007-international exm report.pdf

05093-kolnp-2007-international publication.pdf

05093-kolnp-2007-international search report.pdf

05093-kolnp-2007-others pct form.pdf

05093-kolnp-2007-pct priority document notification.pdf

05093-kolnp-2007-pct request form.pdf

05093-kolnp-2007-translated copy of priority document.pdf

5093-KOLNP-2007-(20-12-2012)-ANNEXURE TO FORM 3.pdf

5093-KOLNP-2007-(20-12-2012)-CORRESPONDENCE.pdf

5093-KOLNP-2007-(20-12-2012)-OTHERS.pdf

5093-KOLNP-2007-(28-09-2012)-ANNEXURE TO FORM 3.pdf

5093-KOLNP-2007-(28-09-2012)-CLAIMS.pdf

5093-KOLNP-2007-(28-09-2012)-CORRESPONDENCE.pdf

5093-KOLNP-2007-(28-09-2012)-DESCRIPTION (COMPLETE).pdf

5093-KOLNP-2007-(28-09-2012)-DRAWINGS.pdf

5093-KOLNP-2007-(28-09-2012)-FORM-1.pdf

5093-KOLNP-2007-(28-09-2012)-FORM-2.pdf

5093-KOLNP-2007-(28-09-2012)-OTHERS.pdf

5093-KOLNP-2007-(29-01-2013)-AMANDED PAGES OF SPECIFICATION.pdf

5093-KOLNP-2007-(29-01-2013)-CORRESPONDENCE.pdf

5093-KOLNP-2007-CANCELLED COPY.pdf

5093-KOLNP-2007-CORRESPONDENCE 1.5.pdf

5093-KOLNP-2007-CORRESPONDENCE 1.6.pdf

5093-KOLNP-2007-CORRESPONDENCE 1.7.pdf

5093-kolnp-2007-CORRESPONDENCE OTHERS 1.1.pdf

5093-KOLNP-2007-CORRESPONDENCE OTHERS 1.2.pdf

5093-KOLNP-2007-CORRESPONDENCE OTHERS 1.3.pdf

5093-KOLNP-2007-CORRESPONDENCE-1.4.pdf

5093-KOLNP-2007-CORRESPONDENCE-1.7.pdf

5093-KOLNP-2007-EXAMINATION REPORT.pdf

5093-kolnp-2007-FORM 18.pdf

5093-KOLNP-2007-FORM 3-1.2.pdf

5093-KOLNP-2007-FORM 3.1.1.pdf

5093-KOLNP-2007-GRANTED-ABSTRACT.pdf

5093-KOLNP-2007-GRANTED-CLAIMS.pdf

5093-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

5093-KOLNP-2007-GRANTED-DRAWINGS.pdf

5093-KOLNP-2007-GRANTED-FORM 1.pdf

5093-KOLNP-2007-GRANTED-FORM 2.pdf

5093-KOLNP-2007-GRANTED-FORM 3.pdf

5093-KOLNP-2007-GRANTED-FORM 5.pdf

5093-KOLNP-2007-GRANTED-SPECIFICATION-COMPLETE.pdf

5093-KOLNP-2007-OTHERS.pdf

5093-KOLNP-2007-PA.pdf

5093-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf

5093-KOLNP-2007-TRANSLATED COPY OF PRIORITY DOCUMENT.pdf

abstract-05093-kolnp-2007.jpg


Patent Number 255601
Indian Patent Application Number 5093/KOLNP/2007
PG Journal Number 10/2013
Publication Date 08-Mar-2013
Grant Date 07-Mar-2013
Date of Filing 31-Dec-2007
Name of Patentee ZHENG, YUNFENG
Applicant Address 5-1-506, DONGCHEN XIAOQU, DONGXIAOKOU TOWN, CHANGPING DISTRICT, BEIJING
Inventors:
# Inventor's Name Inventor's Address
1 WANG, JIANG TIANJIN UNIVERSITY, NO. 92 WEIJIN ROAD, TIANJIN 300072
2 ZHENG, YUNFENG 5-1-506, DONGCHEN XIAOQU, DONGXIAOKOU TOWN, CHANGPING DISTRICT, BEIJING 100085
3 XU, LIN KUNMING INSTITUTE OF ZOOLOGY, THE CHINESE ACADEMY OF SCIENCES, NO.32 JIAOCHANG EAST ROAD, KUNMING, YUNNAN 650223
PCT International Classification Number A61N 2/00
PCT International Application Number PCT/CN2006/001289
PCT International Filing date 2006-06-12
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 200510077042.6 2005-06-15 China