CN103142225A - Electroencephalograph for determining contact status between electrode and scalp and method for determining same - Google Patents
Electroencephalograph for determining contact status between electrode and scalp and method for determining same Download PDFInfo
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Abstract
The invention relates to an electroencephalograph for determining the contact status between an electrode and a scalp and a method for determining the contact status between the electrode and the scalp. The electroencephalograph comprises an electroencephalogram signal detecting circuit and a scalp impedance detecting circuit, wherein the electroencephalogram signal detecting circuit is provided with at least one set of interfaces connected with a reference electrode and a plurality of electrodes to be detected, which are contacted with scalp, through lead wires; and the scalp impedance detecting circuit is independent from the electroencephalogram signal detecting circuit to be connected with the interfaces of the electrodes to be detected and the reference electrode. According to the invention, the electroencephalogram signal detecting circuit and the scalp impedance detecting circuit are respectively detected, the contact status is determined by a threshold value determining method, and the method is simple in circuit, high in circuit anti-interference performance and quick in speed; not only can the detection precision of the scalp impedance be improved, but also the acquiring and the process of the electroencephalogram signal can not be influenced; and the large information content electroencephalogram signal can be most accurately processed, and the scalp impedance information can be most timely processed, so that a product is better in performance.
Description
Technical field
The invention belongs to medical Instrument field, particularly a kind of electroencephalograph and determination methods thereof that electrode and scalp contact condition are judged.
Background technology
Along with the progress and development of science and technology, improving constantly of living standards of the people, also more and more higher to the requirement of medical detection level.The brain electric system plays an important role in clinical diagnosis as a kind of important medical apparatus and instruments that detects brain diseases.But present brain electricity product memory capacity is little, gather lead number less, poor anti jamming capability, stability be also relatively poor, some brain electro-detection equipment does not possess the function of detecting electrode connection, possesses the impedance between brain electricity and electrode and scalp of can not measuring simultaneously of this function.Become the importance of brain research along with biocybernetics method research brain function, the importance of Processig of EEG information is also more and more obvious.Aspect preclinical medicine, because the brain electricity has synthetically reflected neural activity, thereby its research helps the further investigated of neuromechanism in physiology and pathology activity.Aspect clinical medicine, Processig of EEG information not only provides objective basis for the diagnosis of some disease of brain, and provides effective treatment means for some disease of brain.In the research of psychology, psychiatry, Cognitive Science, Processig of EEG information has important learning value and wide application prospect.Therefore, advance brain electro-detection class armarium to develop in depth and breadth to high point, could satisfy the demand of forward position medical applications.
Because EEG signals itself is very faint, can be subject to various impacts in measuring process, produce artifact, and then affect the quality of EEG signals.And the principal element that affects the EEG signals quality has: the noise that the interference that AC power frequency interference, electrode and scalp loose contact are introduced and amplification channel are introduced etc.
Publication number is the Chinese patent of CN2610843, a kind of " brain scalp impedance detector " disclosed, a kind of impedance detection circuit of brain electricity is proposed in patent, the detection signal of the brain electricity of this circuit and the test signal of scalp impedance are mixed in together, amplify by the common large circuit of brain tele-release, then by after high pass and low-pass filtering, two kinds of signals being extracted respectively, obtain corresponding brain electric information and impedance information.EEG signals is the low frequency signal of 0-30Hz, and traditional large circuit of brain tele-release designs for low frequency signal, and is more serious to the decay meeting of high-frequency signal of modulation impedance information, thereby makes the impedance information that draws not accurate enough.publication number is the Chinese patent of CN101199418, a kind of " brain impedance detection circuitry and EEG checking device " disclosed, a kind of impedance detection circuit of brain electricity is proposed in patent, this circuit passes through constant-current source, scalp, earth resistance forms the loop, this circuit is provided with separately an earth resistance and be used for measures the exciting circuit of scalp impedance and test circuit altogether, require in use to contact necessary good with scalp as the electrode of earth resistance, its reaction be not real measurement electrode and the EEG type impedance between reference electrode, complexity and the inaccuracy of test have been increased.
Above-mentioned two open files have all adopted traditional simple alternating current constant-current source as the driving source of human-body biological impedance measurement, what frequency adopted is all lower than 50KHz, calculate its impedance by its virtual value, and in circuit, simple alternating current constant current excitation signal and EEG signals all can be input in the EEG signals testing circuit simultaneously, sine wave signal is easy to the measurement of pcs signal is produced interference, and the circuit of its processing is wanted complicated with respect to other circuit.And resistance and the signal wave phase error measured lower than the simple alternating current constant current excitation signal of 50KHz are large, will produce error when requiring EEG signals to synchronize with the scalp impedance signal in setting time, and good, the bad and three kinds of states that come off that only need in actual application electrode is contacted with scalp judge, and undesired accurately resistance, the simple alternating current constant-current source that therefore adopts is too complicated as the circuit of the driving source of human-body biological impedance measurement.
Summary of the invention
The objective of the invention is to propose a kind of electroencephalograph and determination methods thereof that electrode and scalp contact condition are judged, high frequency characteristics for modulation signal, adopt human body impedance close to the frequency of pure resistance characteristic as excitation, select the long-pending amplifier of high gain-bandwidth, impedance information is distinguished over EEG signals to be processed, thereby improved the accuracy of impedance information, and adopt square wave as driving source, the energy size that electrode and the contact resistance of scalp are obtained compares to judge with setting value contact good with bad.
To achieve these goals, technical scheme of the present invention is:
The electroencephalograph that electrode and scalp contact condition are judged: comprise EEG signals testing circuit and scalp impedance detection circuit, described EEG signals testing circuit is provided with at least one group and connects the tested electrode of a plurality of contact scalps and the EEG signals interface of a reference electrode by conducting wire; Wherein, described scalp impedance detection circuit comprises high frequency pumping loop and scalp impedance acquisition cuicuit; Described high frequency pumping loop comprises that dutycycle is square-wave generator and the multichannel capacitance-resistance charge-discharge circuit of 1:1, described capacitance-resistance charge-discharge circuit is comprised of the first resistance and the first capacitances in series, described square-wave generator output connects a phase inverter, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode interface respectively, and a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with the reference electrode interface; Tested electrode interface is connected the input that connects scalp impedance acquisition cuicuit with the reference electrode interface, the output of scalp impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal.
Scheme is further, and described square-wave generator is that dutycycle is that the frequency of 1:1 is 60KHz to 70KHz square-wave generator.
Scheme is further, and described square-wave generator is that dutycycle is that the frequency of 1:1 is the 64KHz square-wave generator.
Scheme is further, and described the first resistance is 1 megohm, and described the first electric capacity is 4.7 nano farads.
scheme is further that described impedance acquisition cuicuit is linked in sequence and comprises frequency selection circuit, differential amplifier circuit, demodulation amplifying circuit and A/D convertor circuit, described frequency selection circuit comprises the multichannel resistance-capacitance circuit, described resistance-capacitance circuit is comprised of second capacitance series the second resistance, one end connecting analog power cathode of the second resistance, described reference electrode is connected in series with a roadlock capacitive circuit, described a plurality of tested electrode is connected in series with remaining resistance-capacitance circuit respectively, described the second electric capacity be connected the junction point of resistance and connect a follow circuit as output, a plurality of follow circuits that described and a plurality of tested electrodes are connected connect a multichannel and select an analog switch, multichannel selects the output of an analog switch to connect the difference input of differential amplifier circuit together with the follow circuit output that is connected with reference electrode.
Scheme is further, and described the second electric capacity is 4.7 nano farads, and described the second resistance is 20 kilohms.
Scheme is further, and described demodulation amplifying circuit comprises demodulator circuit and signal amplification circuit, and described demodulator circuit comprises the 3rd resistance, the 3rd electric capacity, the 4th resistance, the 5th resistance, the 4th electric capacity; Described the 3rd resistance is connected with the 3rd electric capacity one end, the 3rd electric capacity other end connects respectively the 4th resistance and the 5th resistance one end, the 5th resistance other end connects the 4th electric capacity one end, the 4th resistance and the 4th electric capacity other end connecting analog power cathode, the 5th resistance is connected the input of signal amplification circuit with the link of the 4th electric capacity.
Scheme is further, and described the 3rd resistance is 1 kilohm, and described the 3rd electric capacity is 100 picofarads, and the 4th resistance is 249 kilohms, and the 5th resistance is 10 kilohms, and the 4th electric capacity is 62 picofarads.
Electrode contact state judging method based on the electroencephalograph that electrode and scalp contact condition are judged: comprise EEG signals testing circuit and scalp impedance detection circuit, described EEG signals testing circuit has at least a group interface to connect tested electrode and a reference electrode of a plurality of contact scalps by conducting wire; Described scalp impedance detection circuit comprises high frequency pumping loop and scalp impedance acquisition cuicuit; Described high frequency pumping loop comprises that dutycycle is 60KHz to 70KHz square-wave generator and the multichannel capacitance-resistance charge-discharge circuit of 1:1, described capacitance-resistance charge-discharge circuit is comprised of the first resistance and the first capacitances in series, described square-wave generator output connects a phase inverter, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode respectively, and a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with reference electrode; Tested electrode is connected the input that connects scalp impedance acquisition cuicuit with reference electrode, the output of scalp impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal; It is characterized in that, described impedance measurement method comprises: a scalp impedance magnitude decision threshold table is arranged, obtain scalp impedance value between tested electrode and reference electrode by the scalp impedance detection circuit, impedance value and threshold value table are compared judgement, when impedance value meets contact when coming off threshold value, export electrode contact signal that comes off, when impedance value meets the loose contact threshold value, export an electrode loose contact signal, when impedance value meets the contact good threshold, export an electrode contact good signal.
Scheme is further, described method is further: also have a plurality of tested electrode that a scalp impedance detection circuit connects a plurality of tested electrodes and the connection of EEG signals testing circuit corresponding table one by one, with described scalp impedance detection circuit to the result of determination of tested electrode contact impedance and EEG signals testing circuit to the EEG signals of the tested electrode collection corresponding external equipment that outputs to one by one.
The present invention compared with prior art has following advantage: the testing circuit of the testing circuit of EEG signals and scalp impedance is divided into two-way measures, not only improved the precision of scalp impedance detection, also can not affect simultaneously the acquisition process of EEG signals; The present invention adopts the method for qualitative judgement that contact condition is judged, circuit is simple, and circuit anti-interference is strong, and speed is fast; EEG signals adopts the sigma-delta ADC of high accuracy low speed, the successive approximation type a/d C that the scalp impedance detection is used at a high speed low precision, makes the EEG signals of large information capacity can access the most accurate, scalp impedance information and obtains processing the most timely, makes the performance of product more excellent; Host computer adopts FIR digital filtering network technology that digital brain electrical signal and the digital scalp impedance information that gathers is optimized processing, shows with different identification means, thereby provides stronger basis for estimation for pathological analysis.
Like this, in time obtain the contact impedance state of electrode when measuring EEG signals, just can provide the strongest, foundation the most timely for removing brain electricity artifact.
Below in conjunction with drawings and Examples, the present invention is made a detailed description.
Description of drawings
Fig. 1 is electrical block diagram of the present invention;
Fig. 2 is high frequency pumping equivalent circuit of the present invention;
Fig. 3 is Fig. 2 each point oscillogram;
Fig. 4 is frequency selection circuit, differential amplifier circuit schematic diagram;
Fig. 5 is demodulation amplifying circuit schematic diagram of the present invention.
The specific embodiment
Embodiment 1:
A kind of electroencephalograph embodiment with the impedance detection function: referring to Fig. 1, described electroencephalograph comprises EEG signals testing circuit 1 and scalp impedance detection circuit 2, described EEG signals testing circuit is provided with at least one group and connects the tested electrode 3 of a plurality of contact scalps and the EEG signals interface of a reference electrode 4 by conducting wire, two to three groups or many groups can be set according to the actual needs, and the present embodiment is two groups; Wherein, described scalp impedance detection circuit is independent of the EEG signals testing circuit and is connected with the reference electrode interface with tested electrode interface, the simulation ground and the EEG signals testing circuit that are the scalp impedance detection circuit are separated from each other with simulating, and the scalp impedance signal input of described scalp impedance detection circuit is connected with the reference electrode interface with the tested electrode interface of EEG signals testing circuit respectively.The EEG signals testing circuit is the universal circuit of known use, after the A/D conversion ADC 1-3 of EEG signals through prime filter circuit 1-1, amplifying circuit 1-2, low-speed highly precise of this circuit with collection, after passing through again the signal processing of microprocessor 5, be uploaded to host computer and carry out display analysis.
in embodiment, as shown in Figure 1, described scalp impedance detection circuit comprises high frequency pumping loop 2-1 and impedance acquisition cuicuit 2-2, as shown in Figure 2, described high frequency pumping loop comprises that dutycycle is that the frequency of 1:1 is 60KHz to 70KHz square-wave generator 2-1-1 and multichannel capacitance-resistance charge-discharge circuit 2-1-2, described capacitance-resistance charge-discharge circuit is composed in series by the first resistance R 1 and the first capacitor C 1, described square-wave generator output connects a phase inverter 2-1-3, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode respectively, a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with reference electrode, tested electrode is connected the input that connects the impedance acquisition cuicuit with reference electrode, the output of impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal.Fig. 2 is an equivalent circuit, actual circuit as shown in Figure 1, square wave is to be produced by the high frequency pumping square-wave pulse generator, current-limiting resistance, integrating circuit and block isolating circuit have formed the capacitance-resistance charge-discharge circuit.
Show in the research report of " observation and control technology " 2012 the 32nd volume the 4th interim " multi-frequency and multi-segment human biological electricity impedance measurement system ", the impedance of human body driving frequency during at 50KHz to 100KHz phase error less, namely approaching is the characteristic of pure resistance, in embodiment, due near the 64KHz frequency band, human body impedance is approximate pure resistance characteristic, about 1-10K Ω magnitude, therefore the square-wave generator parameter preferably, described square-wave generator is that dutycycle is that the frequency of 1:1 is the 64KHz square-wave generator.
In embodiment, again due near the 64KHz frequency band, human body impedance is approximate pure resistance characteristic, about 1-10K Ω magnitude, and therefore will access interelectrode equivalent impedance is pure resistance r.In each cycle of square wave, two C1 are that r and two R1 fixed resistances discharge and recharge by the scalp termination.Getting R1 is that 1M Ω, two C1 respectively are 4.7nF.The time constant of circuit is about 4700 μ s like this, and the cycle T of square wave is 16 μ s, Gu discharge and recharge all incomplete at every turn, on electric capacity, voltage waveform is the shape of approximate triangular wave, therefore, parameter preferably, described the first resistance is 1 megohm, described the first electric capacity is 4.7 nano farads, the waveform of each point as shown in Figure 3, the amplitude that the information of scalp impedance has been included in B1 and B2 electric potential waveform has suffered.
in embodiment, referring to Fig. 4, described impedance acquisition cuicuit is linked in sequence and comprises frequency selection circuit, differential amplifier circuit 2-2-2, demodulation amplifying circuit 2-2-4 and A/D convertor circuit 2-2-5, described frequency selection circuit comprises the multichannel resistance-capacitance circuit, resistance-capacitance circuit is comprised of second capacitor C 2 serial connection the second resistance R 2, one end connecting analog power cathode of the second resistance, described reference electrode is connected in series with a roadlock capacitive circuit, described a plurality of tested electrode is connected in series with remaining resistance-capacitance circuit respectively, in order to reduce the impact on the EEG signals testing circuit, improve the input impedance of differential amplifier circuit, the second electric capacity be connected the junction point of resistance and connect a follow circuit 2-2-1 who is formed by operational amplifier as output, the follow circuit output that tested electrode is connected with reference electrode connects the difference input of differential amplifier circuit, in embodiment, the amplification of differential amplifier circuit is 30 times.
In embodiment, frequency selection circuit is the 64Khz frequency selection circuit, and wherein C2 is 4.7 nano farads (nF), and R2 is 20 kilohms (K Ω).
In embodiment, referring to Fig. 4, a plurality of follow circuits that described and a plurality of tested electrodes are connected connect a multichannel and select an analog switch 2-2-3, multichannel selects the output of an analog switch to connect the difference input of differential amplifier circuit together with the follow circuit output that is connected with reference electrode, and multichannel selects the control end of an analog switch to connect microprocessor.
In embodiment, described demodulation amplifying circuit comprises demodulator circuit and signal amplification circuit (secondary amplification), and described demodulator circuit comprises the 3rd resistance R 3, the 3rd capacitor C 3, the 4th resistance R 4, the 5th resistance R 5, the 4th capacitor C 4; Described the 3rd resistance is connected with the 3rd electric capacity one end, the 3rd electric capacity other end connects respectively the 4th resistance and the 5th resistance one end, the 5th resistance other end connects the 4th electric capacity one end, the 4th resistance and the 4th electric capacity other end connecting analog power cathode, the 5th resistance is connected the input of signal amplification circuit with the link of the 4th electric capacity.
In embodiment, demodulator circuit is the demodulation to the 64Khz signal, and wherein, R3 is 1 kilohm (K Ω), and C3 is 100 picofarads (PF), and R4 is 249 kilohms (K Ω), and R5 is 10 kilohms (K Ω), and C4 is 62 picofarads (PF).
in above-described embodiment, the testing circuit of scalp impedance signal is added in forward and high-frequency carrier signal negative anode and the negative terminal of brain wave acquisition signal, EEG signals with the scalp impedance information just is added on high-frequency carrier signal, with the high-frequency signal of impedance information by integrating circuit and high-pass filtering network after the long-pending difference amplifier of access high gain-bandwidth, enter two-level operating amplifier after the filtering of intergrade, signal after amplification is again through hanging down at a high speed the successive approximation type a/d C of precision, according to different energy threshold scopes, judge the contact impedance of electrode, thereby provide the state of electrode access, namely contact is good, loose contact, three kinds of states come off, on brain electricity box, the control display lamp goes out, dodge or bright three kinds of states that come the indicating electrode access, be that lamp goes out the expression contact well, lamp dodges the expression loose contact, the bright expression of lamp comes off.
The Treatment Analysis of EEG signals and scalp impedance information comprises the Treatment Analysis of EEG signals, is used for the EEG signals of continuous acquisition is carried out digital filtering, then filtered data is carried out the figure conversion, at last waveform is shown; The Treatment Analysis of scalp impedance information is used for timing acquiring scalp impedance information, by timing acquiring scalp impedance signal, according to different sampled value judgement termination values, and shows.Identify when gathering, identify with different colors or flag event mode, namely with red waveform and the printed words labelling state that comes off that comes off, with yellow waveform and loose contact printed words labelling loose contact state, with normal color labelling contact kilter, such mark mode provides stronger basis for estimation for pathological analysis when checking the review waveform.
In embodiment, it is the characteristics of the present embodiment that minute two-way of the testing circuit of EEG signals and scalp impedance detection circuit is processed; And adopt low speed high-precision A/D conversion adc circuit, scalp impedance signal to adopt the successive approximation type a/d C of low essence at a high speed for EEG signals.
Embodiment 2:
the electrode contact state judging method embodiment of the electroencephalograph that judges based on 1 pair of electrode of embodiment and scalp contact condition: comprise EEG signals testing circuit and scalp impedance detection circuit, at least one group interface of described EEG signals testing circuit connects tested electrode and a reference electrode of a plurality of contact scalps by conducting wire, described scalp impedance detection circuit comprises high frequency pumping loop and scalp impedance acquisition cuicuit, described high frequency pumping loop comprises that dutycycle is 60KHz to 70KHz square-wave generator and the multichannel capacitance-resistance charge-discharge circuit of 1:1, described capacitance-resistance charge-discharge circuit is comprised of the first resistance and the first capacitances in series, described square-wave generator output connects a phase inverter, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode interface respectively, a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with reference electrode, tested electrode is connected the input that connects scalp impedance acquisition cuicuit with reference electrode, the output of scalp impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal, wherein, described impedance measurement method comprises: a scalp impedance magnitude decision threshold table is arranged, obtain scalp impedance value between tested electrode and reference electrode by the scalp impedance detection circuit, impedance value and threshold value table are compared judgement, when impedance value meets contact when coming off threshold value, export electrode contact signal that comes off, when impedance value meets the loose contact threshold value, export an electrode loose contact signal, when impedance value meets the contact good threshold, export an electrode contact good signal.Described scalp electrical impedance signal is actually the electric potential signal at scalp equivalent resistance r resistance two ends in Fig. 2.When electrode and scalp do not connect fully, electrode is in the state of coming off, that is to say that in Fig. 2, the r resistance is infinitely great, equivalent circuit belongs to and opens circuit, two waveforms that are added in so the single spin-echo at difference amplifier two ends are done and are obtained maximum and minima after poor, can be judged to be to lead according to threshold value to come off.When electrode and scalp contact when good fully, electrode does not come off, and in Fig. 2, r resistance is very little, and B1 and B2 can regard isoelectric level as, obtain after differential amplifier circuit with reference to the zero potential value so.Can being judged to be this moment leads connects well.Marginal situation can be judged to be the good situation of contact fully of leading not.The value of three kinds of above-mentioned situations is stored in memorizer as judgment threshold.
In embodiment, described method is further: have scalp impedance detection circuit to connect a plurality of tested electrodes and a plurality of tested electrodes of EEG signals testing circuit connection corresponding table one by one, with described scalp impedance detection circuit to the result of determination of tested electrode contact impedance and EEG signals testing circuit to the EEG signals of the tested electrode collection corresponding external equipment that outputs to one by one.
in above-described embodiment, the detection of scalp impedance signal is added in positive and high-frequency carrier signal negative anode and the negative terminal of brain wave acquisition signal, EEG signals with the scalp impedance information just is added on high-frequency carrier signal, with the high-frequency signal of impedance information by integrating circuit and high-pass filtering network after the long-pending difference amplifier of access high gain-bandwidth, enter two-level operating amplifier after the filtering of intergrade, signal after amplification is again through hanging down at a high speed the successive approximation type a/d C(A/D change-over circuit of precision) circuit, according to different energy threshold scopes (because be not the constant-current source form, do not know the size of electric current, therefore with energy value analog electrical resistance rather than real resistance value).Judge the contact impedance state of electrode, thereby provide the state of electrode access, i.e. contact is good, loose contact, three kinds of states come off, on brain electricity box, control that display lamp goes out, sudden strain of a muscle or bright three kinds of states that come the indicating electrode access, be that lamp goes out the expression contact well, lamp dodges the expression loose contact, and the bright expression of lamp comes off.
The Treatment Analysis of EEG signals and scalp impedance information comprises the Treatment Analysis of EEG signals, is used for the EEG signals of continuous acquisition is carried out digital filtering, then filtered data is carried out the figure conversion, at last waveform is shown; The Treatment Analysis of scalp impedance information is used for timing acquiring scalp impedance information, by timing acquiring scalp impedance signal, according to different sampled value judgement termination values, and shows.Identify when gathering, identify with different colors or flag event mode, namely with red waveform and the printed words labelling state that comes off that comes off, with yellow waveform and loose contact printed words labelling loose contact state, with normal color labelling contact kilter, such mark mode provides stronger basis for estimation for pathological analysis when checking the review waveform.
Claims (10)
1. the electroencephalograph that electrode and scalp contact condition is judged: comprise EEG signals testing circuit and scalp impedance detection circuit, described EEG signals testing circuit is provided with at least one group and connects the tested electrode of a plurality of contact scalps and the EEG signals interface of a reference electrode by conducting wire; It is characterized in that, described scalp impedance detection circuit comprises high frequency pumping loop and scalp impedance acquisition cuicuit; Described high frequency pumping loop comprises that dutycycle is square-wave generator and the multichannel capacitance-resistance charge-discharge circuit of 1:1, described capacitance-resistance charge-discharge circuit is comprised of the first resistance and the first capacitances in series, described square-wave generator output connects a phase inverter, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode interface respectively, and a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with the reference electrode interface; Tested electrode interface is connected the input that connects scalp impedance acquisition cuicuit with the reference electrode interface, the output of scalp impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal.
2. the electroencephalograph that electrode and scalp contact condition are judged according to claim 1, is characterized in that, described square-wave generator is that dutycycle is that the frequency of 1:1 is 60KHz to 70KHz square-wave generator.
3. the electroencephalograph that electrode and scalp contact condition are judged according to claim 1, is characterized in that, described square-wave generator is that dutycycle is that the frequency of 1:1 is the 64KHz square-wave generator.
4. the electroencephalograph that electrode and scalp contact condition are judged according to claim 1, is characterized in that, described the first resistance is 1 megohm, and described the first electric capacity is 4.7 nano farads.
5. the electroencephalograph that electrode and scalp contact condition are judged according to claim 1, is characterized in that, described impedance acquisition cuicuit is linked in sequence and comprises frequency selection circuit, differential amplifier circuit, demodulation amplifying circuit and A/D convertor circuit, described frequency selection circuit comprises the multichannel resistance-capacitance circuit, described resistance-capacitance circuit is comprised of second capacitance series the second resistance, one end connecting analog power cathode of the second resistance, described reference electrode is connected in series with a roadlock capacitive circuit, described a plurality of tested electrode is connected in series with remaining resistance-capacitance circuit respectively, described the second electric capacity be connected the junction point of resistance and connect a follow circuit as output, a plurality of follow circuits that described and a plurality of tested electrodes are connected connect a multichannel and select an analog switch, multichannel selects the output of an analog switch to connect the difference input of differential amplifier circuit together with the follow circuit output that is connected with reference electrode.
6. the electroencephalograph that electrode and scalp contact condition are judged according to claim 5, is characterized in that, described the second electric capacity is 4.7 nano farads, and described the second resistance is 20 kilohms.
7. the electroencephalograph that electrode and scalp contact condition are judged according to claim 5, it is characterized in that, described demodulation amplifying circuit comprises demodulator circuit and signal amplification circuit, and described demodulator circuit comprises the 3rd resistance, the 3rd electric capacity, the 4th resistance, the 5th resistance, the 4th electric capacity; Described the 3rd resistance is connected with the 3rd electric capacity one end, the 3rd electric capacity other end connects respectively the 4th resistance and the 5th resistance one end, the 5th resistance other end connects the 4th electric capacity one end, the 4th resistance and the 4th electric capacity other end connecting analog power cathode, the 5th resistance is connected the input of signal amplification circuit with the link of the 4th electric capacity.
8. the electroencephalograph that electrode and scalp contact condition are judged according to claim 7, is characterized in that, described the 3rd resistance is 1 kilohm, described the 3rd electric capacity is 100 picofarads, the 4th resistance is 249 kilohms, and the 5th resistance is 10 kilohms, and the 4th electric capacity is 62 picofarads.
9. based on the electrode contact state judging method of the electroencephalograph that electrode and scalp contact condition are judged: comprise EEG signals testing circuit and scalp impedance detection circuit, described EEG signals testing circuit has at least a group interface to connect tested electrode and a reference electrode of a plurality of contact scalps by conducting wire; Described scalp impedance detection circuit comprises high frequency pumping loop and scalp impedance acquisition cuicuit; Described high frequency pumping loop comprises that dutycycle is 60KHz to 70KHz square-wave generator and the multichannel capacitance-resistance charge-discharge circuit of 1:1, described capacitance-resistance charge-discharge circuit is comprised of the first resistance and the first capacitances in series, described square-wave generator output connects a phase inverter, the output of phase inverter connects a roadlock and holds the charge-discharge circuit resistance terminal, be connected with square-wave generator output after all the other capacitance-resistance charge-discharge circuit resistance terminal parallel connections, the capacitance-resistance series circuit capacitance terminal of described parallel connection is connected with tested electrode respectively, and a described roadlock holds the charge-discharge circuit capacitance terminal and is connected with reference electrode; Tested electrode is connected the input that connects scalp impedance acquisition cuicuit with reference electrode, the output of scalp impedance acquisition cuicuit is passed to microprocessor with scalp electrical impedance signal; It is characterized in that, described impedance measurement method comprises: a scalp impedance magnitude decision threshold table is arranged, obtain scalp impedance value between tested electrode and reference electrode by the scalp impedance detection circuit, impedance value and threshold value table are compared judgement, when impedance value meets contact when coming off threshold value, export electrode contact signal that comes off, when impedance value meets the loose contact threshold value, export an electrode loose contact signal, when impedance value meets the contact good threshold, export an electrode contact good signal.
10. the electrode contact state judging method of the electroencephalograph based on electrode and scalp contact condition are judged according to claim 9: it is characterized in that, described method is further: also have a plurality of tested electrode that a scalp impedance detection circuit connects a plurality of tested electrodes and the connection of EEG signals testing circuit corresponding table one by one, with described scalp impedance detection circuit to the result of determination of tested electrode contact impedance and EEG signals testing circuit to the EEG signals of the tested electrode collection corresponding external equipment that outputs to one by one.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2610843Y (en) * | 2003-04-22 | 2004-04-14 | 上海诺诚电气有限公司 | Scalp impedance detector |
| US6882166B2 (en) * | 2001-07-06 | 2005-04-19 | Aspect Medical Systems, Inc. | System and method for measuring the validity of a bioelectric impedance measurement in the presence of interference |
| CN101076281A (en) * | 2004-06-10 | 2007-11-21 | 荷兰联合利华有限公司 | Apparatus and method for reducing interference |
| CN101199418B (en) * | 2006-12-12 | 2010-06-02 | 深圳迈瑞生物医疗电子股份有限公司 | Brain impedance detection circuitry and EEG checking device |
| US20110251817A1 (en) * | 2010-04-12 | 2011-10-13 | Reproductive Research Technologies, Llp | Method and apparatus to determine impedance variations in a skin/electrode interface |
| US8089283B2 (en) * | 2007-08-10 | 2012-01-03 | Consolidate Research, Inc. | Apparatus and method for high-speed determination of bioelectric electrode impedances |
| US20120071781A1 (en) * | 2010-09-10 | 2012-03-22 | Neuronetrix Solutions, Llc | Electrode system with in-band impedance detection |
-
2013
- 2013-03-27 CN CN201310106008.1A patent/CN103142225B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6882166B2 (en) * | 2001-07-06 | 2005-04-19 | Aspect Medical Systems, Inc. | System and method for measuring the validity of a bioelectric impedance measurement in the presence of interference |
| CN2610843Y (en) * | 2003-04-22 | 2004-04-14 | 上海诺诚电气有限公司 | Scalp impedance detector |
| CN101076281A (en) * | 2004-06-10 | 2007-11-21 | 荷兰联合利华有限公司 | Apparatus and method for reducing interference |
| CN101199418B (en) * | 2006-12-12 | 2010-06-02 | 深圳迈瑞生物医疗电子股份有限公司 | Brain impedance detection circuitry and EEG checking device |
| US8089283B2 (en) * | 2007-08-10 | 2012-01-03 | Consolidate Research, Inc. | Apparatus and method for high-speed determination of bioelectric electrode impedances |
| US20110251817A1 (en) * | 2010-04-12 | 2011-10-13 | Reproductive Research Technologies, Llp | Method and apparatus to determine impedance variations in a skin/electrode interface |
| US20120071781A1 (en) * | 2010-09-10 | 2012-03-22 | Neuronetrix Solutions, Llc | Electrode system with in-band impedance detection |
Non-Patent Citations (2)
| Title |
|---|
| 曾利浪等: "脑电图机电极与头皮接触阻抗的检测", 《上海生物医学工程》, vol. 24, no. 3, 30 September 2003 (2003-09-30), pages 57 - 59 * |
| 李窦哲等: "高性能生物电测量电路设计与参数自动测试", 《测试技术学报》, vol. 24, no. 2, 15 March 2010 (2010-03-15), pages 111 - 116 * |
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