SELECTION OF SENSORY STIMULI FOR NEUROFEEDBACK TRAINING

Abstract

The invention provides for a medical instrument (100, 400, 500, 600) comprising an activity measurement system (106) configured for measuring brain activity data (138) from a subject (102). The medical instrument further comprises a stimulus presentation system (108) configured for providing sensory stimulus to the subject. The medical instrument further comprises a memory (130) for storing machine executable instructions (132) and for storing a stimulus reinforcer database (134). The stimulus reinforcer database comprises entries. Each entry comprises commands configured for controlling the stimulus presentation system to provide the sensory stimulus to the subject. The medical instrument further comprises a processor (120) for controlling the medical instrument. Execution of the machine executable instructions causes the processor to: control (200) the stimulus presentation system with a set of entries (136) selected from the stimulus reinforcer database to repeatedly provide sensory stimulus to the subject; control (202) the activity measurement system for performing the measurement of the brain activity data during each sensor stimulus; select (204) a chosen entry (140) from the set of entries using the brain activity data; and store (206) the chosen entry in the memory.

Claims

1. A medical instrument comprising: an activity measurement system configured for measuring brain activity data from a subject; a stimulus presentation system configured for providing sensory stimulus to the subject; a memory for storing machine executable instructions and for storing a stimulus reinforcer database, wherein the stimulus reinforcer database comprises entries, wherein each entry comprises commands configured for controlling the stimulus presentation system to provide the sensory stimulus to the subject; a processor for controlling the medical instrument, wherein execution of the machine executable instructions causes the processor to: control the stimulus presentation system with a set of entries selected from the stimulus reinforcer database to repeatedly provide sensory stimulus to the subject; control the activity measurement system for performing the measurement of the brain activity data during each sensor stimulus; select a chosen entry from the set of entries using the brain activity data such that the brain activity of the subject is maximized; store the chosen entry in the memory; receive neurofeedback training instructions; modify the neurofeedback training instructions by incorporating commands from the chosen entry; and control the stimulus presentation system with the modified neurofeedback training instructions.

2. The medical instrument of claim 1, wherein the sensory stimulus comprises any one of the following: an animation, an animated display of a thermometer, and expanding and contracting circle, an animation of a bird which changes a flying state, a display of an image representing a reward, a generation of a tone as a reward, a generation of a chosen melody as a reward, and combinations thereof.

3. The medical instrument of claim 1, wherein the activity measurement system further comprises a respiration measurement system for acquiring respiration data descriptive of a respiration state of the subject, wherein the stimulus reinforcer database further contains respiration indicator entries comprising commands configured controlling the stimulus presentation system for indicating a desired breathing phase or a desired breathing rate to the subject, wherein execution of the machine executable instructions further causes the processor to: present the respiration indicator to the subject during the controlling of the stimulus presentation with the set of entries from the database to repeatedly provide sensory stimulus to the subject; control the respiration measurement system for performing the acquisition of the respiration data during the controlling of the stimulus presentation with the set of entries from the database to repeatedly provide sensory stimulus to the subject; and store a chosen respiration indicator entry from the respiration indicator entries using the respiration data.

4. The medical instrument of claim 3, wherein the breathing indicator comprises any one of the following: an animation that is controlled using the respiration data, and animation of an expanding and contracting circle that is controlled with the resipiration data to match a breathing phase of the subject, and a sinusoidal tone whose frequency is changed using the respiration data.

5. The medical instrument of claim 1, wherein the stimulus presentation system is configured for providing stimulus to more than one sense simultaneously.

6. The medical instrument of claim 1, wherein the stimulus presentation system comprises any one of the following: a visual display, a virtual reality headset, a headphone, an audio speaker, a subwoofer, a tactical feedback system, a heater, a cooler, an instruction display for providing manual tactile feedback instructions, and combinations thereof.

7. The medical instrument of claim 1, wherein the neurofeedback entry is chosen using any one of the following: a neural network: a predetermined criteria; a set of rules; and combinations thereof.

8. The medical instrument of claim 1, wherein the brain activity measurement system comprises a magnetic resonance imaging system.

9. The medical instrument of claim 8, wherein the magnetic resonance imaging system is configured for measuring the brain activity data from the subject using any one of the following: blood oxygenation level dependent functional magnetic resonance imaging measurements from a region of interest, and measuring neural activity in the amygdala.

10. The medical instrument of claim 9, wherein the stimulus presentation system comprises an active noise cancelling headphones configured for providing audio stimulus to the subject.

11. The medical instrument of claim 1, wherein the brain activity measurement system comprises an electroencephalography system.

12. The medical instrument of claim 1, wherein the brain activity measurement system comprises a magnetoencephalography system.

13. The medical system of claim 8, wherein the activity measurement system further comprises an electroencephalography system, wherein execution of the machine executable instructions are configured such that the brain activity data measured during each sensor stimulus comprises magnetic resonance imaging data measured with the magnetic resonance imaging system and EEG data measured with the electroencephalography system, wherein the machine executable instructions are further configured such that during the controlling of the stimulus presentation system with the modified neurofeedback training instructions only the electroencephalography system is used for acquiring brain activity data.

14. A computer program product comprising machine executable instructions for execution by a processor controlling a medical instrument, wherein the medical instrument comprises an activity measurement system configured for measuring brain activity data from a subject and a stimulus presentation system configured for providing sensory stimulus to the subject, wherein execution of the machine executable instructions causes the processor to: control the stimulus presentation system with a set of entries from a stimulus reinforcer database to repeatedly provide sensory stimulus to the subject, wherein the stimulus reinforcer database comprises entries, wherein each entry comprises commands configured for controlling the stimulus presentation system to provide the sensory stimulus to the subject; control the activity measurement system for performing the measurement of the brain activity data during each sensor stimulus; select a chosen entry from the set of entries using the brain activity data such that the brain activity of the subject is maximized; and store the chosen entry in the memory. receive neurofeedback training instructions; modify the neurofeedback training instructions by incorporating commands from the chosen entry; and control the stimulus presentation system with the modified neurofeedback training instructions.

15. A method of operating a medical instrument, wherein the medical instrument comprises an activity measurement system configured for measuring brain activity data from a subject and a stimulus presentation system configured for providing sensory stimulus to the subject, wherein the method comprises: controlling the stimulus presentation system with a set of entries from a stimulus reinforcer database to repeatedly provide sensory stimulus to the subject, wherein the stimulus reinforcer database comprises entries, wherein each entry comprises commands configured for controlling the stimulus presentation system to provide the sensory stimulus to the subject; controlling the activity measurement system for performing the measurement of the brain activity data during each sensor stimulus; selecting a chosen entry from the set of entries using the brain activity data such that the brain activity of the subject is maximized; storing the chosen entry in the memory; receive neurofeedback training instructions; modify the neurofeedback training instructions by incorporating commands from the chosen entry; and control the stimulus presentation system with the modified neurofeedback training instructions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In the following preferred embodiments of the invention will be described, by way of example only, and with reference to the drawings in which:

[0063] FIG. 1 illustrates an example of a medical instrument;

[0064] FIG. 2 shows a flow chart which illustrates a method of using the medical instrument of FIG. 1;

[0065] FIG. 3 shows a flow chart which illustrates a further method of using the medical instrument of FIG. 1;

[0066] FIG. 4 illustrates a further example of a medical instrument;

[0067] FIG. 5 illustrates a further example of a medical instrument;

[0068] FIG. 6 illustrates a further example of a medical instrument;

[0069] FIG. 7 illustrates a implementation of a system for generating modified neurofeedback training instructions;

[0070] FIG. 8 illustrates an example of an animation of a thermometer;

[0071] FIG. 9 shows an animation of an expanding and/or contracting sphere;

[0072] FIG. 10 shows an animation of a flying bird;

[0073] FIG. 11 illustrates a number of rewards which can be presented to a subject during neurofeedback training;

[0074] FIG. 12 illustrates an example of a visual breathing indicator; and

[0075] FIG. 13 illustrates an example of an audible breathing indicator.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0076] Like numbered elements in these figures are either equivalent elements or perform the same function. Elements which have been discussed previously will not necessarily be discussed in later figures if the function is equivalent.

[0077] FIG. 1 illustrates an example of a medical instrument 100. The medical instrument is shown as containing a subject support 104 which supports a subject 102. The medical instrument 100 is further shown as comprising an activity measurement system 106 that is configured for measuring brain activity data from the subject 102. The activity measurement system may be any system which is used to quantitatively measure the brain function or amount of brain activity of the subject 102. Several examples of this may be a magnetic resonance imaging system, an EEG system, and a MEG system. In some instances, the magnetic resonance imaging system and the EEG system could both be combined. The medical instrument 100 is further shown as containing a stimulus presentation system 108.

[0078] The stimulus presentation system may comprise elements which are able to present various stimuli to one or more senses of the subject 102. FIG. 1 illustrates several different examples. The subject 102 is shown as wearing a pair of virtual reality goggles 110. As an alternative to virtual reality goggles there may be a screen or display which is visible to the subject 102. The subject 102 is also shown as wearing headphones 112. The headphones may be used to present an audio stimulus to the subject 114. An alternative to the headphones 112 would be the use of speakers and/or subwoofers. The use of headphones 112 may be particularly beneficial because they may be noise cancelling headphones and may be useful in reducing extraneous stimuli also. The stimulus presentation system 108 is further shown as comprising a body temperature control system 114.

[0079] The body temperature control system may for example be used to raise or lower an external temperature the subject 102 is exposed to. The stimulus presentation system 108 is further shown as containing a tactile feedback system 116. This for example may be used for providing a tactile stimulus to the subject 102. As an alternative to a tactile feedback system 116 there may be a display which displays instructions to a helper which manually provides tactile feedback to the subject 102. Connections between the stimulus presentation system 108 and the various elements of it are not displayed. These may be either wired and/or wireless connections.

[0080] The medical instrument 100 is further shown as comprising a computer 118. The computer comprises a processor 120. The processor 120 is intended to represent one or more processors that may be within the same computing device or may even be distributed amongst various locations or different computing devices. The processor 120 is in communication with a hardware interface 122 that enables the processor 120 to control the other components of the medical instrument 100. The processor 120 is further in communication with an optional user interface 124 that may be used for displaying and/or receiving data from a subject. The processor 120 is further in communication with a memory 130. The memory 130 may be any memory which is accessible to the processor 120. It may for example be volatile or non-volatile memory and may also represent a storage medium such as a hard drive or optical disc. The memory 130 is shown as containing machine-executable instructions 132.

[0081] Execution of the machine-executable instructions 132 by the processor 120 enable it to control the operation and function of the medical instrument 100. The machine-executable instructions 132 may also enable the processor 120 to perform various data processing and image processing tasks. The memory 130 is further shown as containing a stimulus reinforcer database 134. The stimulus reinforcer database 134 comprises entries. Each entry comprises commands configured for controlling the stimulus presentation system to provide the sensory stimulus to the subject. The stimulus reinforcer database 134 may be thought of as a collection of possible stimuli which may be presented to the subject 102. The activity measurement system 106 is then used to measure the subject's response 102 to the various stimulus of the stimulus reinforcer database 134 by measuring the brain activity of the subject. The memory 130 is shown as containing a set of entries 136 selected from the stimulus reinforcer database 134.

[0082] These for example may be a predetermined set of entries 136 or may be selected on the fly using a set of rules or other conditions. Each of the set of entries 136 is then used to control the stimulus presentation system 108 and simultaneously brain activity data 138 is acquired. The brain activity data 138 is then a quantitatively measured response of the subject 102 to each of the set of entries 136. The memory 130 is further shown as containing a chosen entry 140. The chosen entry 140 may for example be one of the set of entries 136 that was selected using the brain activity data 138. A set of predetermined criteria or other selection criteria may be used to select the chosen entry 140. Due to the brain activity data 138 the chosen entry 140 can be used to optimize the subject's response during for example neurofeedback training.

[0083] The memory 130 is further shown as containing optional neurofeedback training instructions 142. The neurofeedback training instructions 142 are instructions which control the medical instrument 100 to control the stimulus presentation system 108 such that the subject 102 is trained using neurofeedback techniques. The memory 130 is further shown as containing modified neurofeedback training instructions 144. The modified neurofeedback training instructions 144 were modified using the chosen entry 140. For example, the optional neurofeedback training instructions 142 may be constructed such that they are generally applicable or usable for subjects in general. However, the brain activity data 138 was used to select a particular stimulus that the subject 102 responded to. This may then be used to optimize or improve and create the modified neurofeedback training instructions 144.

[0084] FIG. 2 shows a flowchart which illustrates a method of operating the medical instrument 100 of FIG. 1. First in step 200 the stimulus presentation system 108 is controlled with the set of entries 136 from the stimulus reinforcer database 134 to repeatedly provide sensory stimulus to the subject 102. Next in step 202 the activity measurement system 106 is controlled to acquire the brain activity data 138 during each sensor stimulus which is caused by each of the set of entries. Next in step 204 a chosen entry 140 is selected from the set of entries 136 using the brain activity data 138. Finally, in step 206 the chosen entry 140 is stored in the memory 130 for further use.

[0085] FIG. 3 shows a figure which illustrates a further method of operating the medical instrument 100 shown in FIG. 1. In FIG. 3 the method starts out with the first four steps of FIG. 2. After steps 200-206 have been performed the method proceeds to step 300. In step 300 the neurofeedback training instructions 300 are received. Next in step 302 the neurofeedback training instructions are modified by incorporating commands from the chosen entry 140. And finally, in step 304, the stimulus presentation system is controlled by executing the modified neurofeedback training instructions 144.

[0086] It should be noted that during the execution of the modified neurofeedback training instructions 144 additional brain activity data 138 can be acquired. This for example could be used to measure the effectiveness of the neurofeedback training instructions as they are used. For example if it is found that the neurofeedback training instructions are losing their effectiveness the chosen entry 140 can be switched for example by going through and repeating the process of screening all of the set of entries using the brain activity data 138 or for example, if the brain activity data indicates that there are several highest or several more effective ways of stimulating the subject 102 the chosen entry 140 can be switched. This may even be performed on the fly.

[0087] FIG. 4 illustrates a further example of a medical instrument 400. The medical instrument 400 of FIG. 4 is different than the one depicted in FIG. 1. In this example the medical instrument 400 is shown as comprising an EEG system 402. The EEG system 402 is the activity measurement system 106. If the activity measurement system 106 comprises an MRI system or an MEG system it may be expensive or difficult to provide to all training locations. The subject 102 could for example be sent to a central examining station or area where the medical instrument 100 of FIG. 1 comprises an MEG system or an MRI system. The modified neurofeedback training instructions 144 can then be transferred to a different medical instrument 400. The memory 130 is shown as containing the modified neurofeedback training instructions 144. The neurofeedback training can then be performed using the more cost effect EEG system 402.

[0088] The medical instrument 400 depicted in FIG. 4, could also be able to perform the methods depicted in FIGS. 1 and 2 using the EEG system. However, FIG. 4 illustrates that once the chosen entry, which indicates an effective stimulus that can be used for a particular subject, is determined it can be transported to other locations and used with other hardware configurations. This could for example be integrated into patient records or data carriers that the subject brings to training.

[0089] Because the choice of the chosen entry is transportable the overall medical instrument could in some examples considered to be a combination of the instruments shown in FIG. 1 and FIG. 4. The various components may therefore be in some instances distributed.

[0090] FIG. 5 illustrates a further example of a medical instrument 500. The medical instrument 500 of FIG. 5 is similar to the medical instrument 100 of FIG. 1 except there is now additionally a respiration belt 502. The respiration belt 502 is able to send a signal as the subject 102 expands and contracts his or her thorax during breathing. The respiration belt 502 is an example of a respiration measurement system. The respiration belt 502 acquires respiration data 506. The memory 130 is further shown as containing respiration indicator entries 504. For example, the audio 112, the visual 110 or the tactile 116 could be used to indicate a breathing rate or phase that is desired to the subject 102. The respiration indicator entries 504 may provide different ways of presenting this to the subject 102.

[0091] For example, the position or expansion of an animation or other object in the visual system 110 may be used to represent a respiration phase. The respiration indicator entries 504 provide several different possibilities which can be tested directly on the subject 102. During the measurement of the brain activity data 138 the respiration data 506 can also be recorded and stored in the memory 130. Various respiration indicator entries 504 can be presented with the different choices presented by the set of entries 136. When the chosen entry 140 is selected a chosen respiration indicator 508 from the respiration indicator entries 504 can be selected using the respiration data 506. The control of the subject's 102 respiration using the chosen respiration indicator 508 may help with the effectiveness of neurofeedback training. The presentation of various respiration indicators at the same time as the different stimulus reinforcers indicated by the set of entries may help to select a means of presenting the respiration phase or rate to the subject 102 that is most compatible with the chosen entry 140.

[0092] FIG. 6 illustrates a further example of a medical instrument 600. In this example the activity measurement system 106 comprises an EEG system 402 and a magnetic resonance imaging system 602. Although the EEG 402 and the magnetic resonance imaging system 602 are both depicted in FIG. 6 the medical instrument 600 could be constructed also with just the EEG system 402 and just the magnetic resonance imaging system 602. However, the EEG system 402 and the magnetic resonance imaging system 602 acquire complimentary data which can be used to improve the quality of the chosen entry 140.

[0093] The magnetic resonance imaging system 602 comprises a magnet 604. The magnet 604 is a superconducting cylindrical type magnet with a bore 606 through it. The use of different types of magnets is also possible; for instance it is also possible to use both a split cylindrical magnet and a so called open magnet. A split cylindrical magnet is similar to a standard cylindrical magnet, except that the cryostat has been split into two sections to allow access to the iso-plane of the magnet, such magnets may for instance be used in conjunction with charged particle beam therapy. An open magnet has two magnet sections, one above the other with a space in-between that is large enough to receive a subject: the arrangement of the two sections area similar to that of a Helmholtz coil. Open magnets are popular, because the subject is less confined. Inside the cryostat of the cylindrical magnet there is a collection of superconducting coils. Within the bore 606 of the cylindrical magnet 604 there is an imaging zone 608 where the magnetic field is strong and uniform enough to perform magnetic resonance imaging. A region of interest 609 is shown within the imaging zone 608. The magnetic resonance data that is acquired typically acquired for the region of interest. A subject 102 is shown as being supported by a subject support 104 such that at least a portion of the subject 102 is within the imaging zone 608 and the region of interest 609.

[0094] Within the bore 606 of the magnet there is also a set of magnetic field gradient coils 610 which is used for acquisition of preliminary magnetic resonance data to spatially encode magnetic spins within the imaging zone 608 of the magnet 604. The magnetic field gradient coils 610 connected to a magnetic field gradient coil power supply 612. The magnetic field gradient coils 610 are intended to be representative. Typically magnetic field gradient coils 610 contain three separate sets of coils for spatially encoding in three orthogonal spatial directions. A magnetic field gradient power supply supplies current to the magnetic field gradient coils. The current supplied to the magnetic field gradient coils 610 is controlled as a function of time and may be ramped or pulsed.

[0095] Adjacent to the imaging zone 608 is a radio-frequency coil 614 for manipulating the orientations of magnetic spins within the imaging zone 608 and for receiving radio transmissions from spins also within the imaging zone 608. The radio frequency antenna may contain multiple coil elements. The radio frequency antenna may also be referred to as a channel or antenna. The radio-frequency coil 614 is connected to a radio frequency transceiver 616. The radio-frequency coil 614 and radio frequency transceiver 516 may be replaced by separate transmit and receive coils and a separate transmitter and receiver. It is understood that the radio-frequency coil 614 and the radio frequency transceiver 516 are representative. The radio-frequency coil 614 is intended to also represent a dedicated transmit antenna and a dedicated receive antenna. Likewise the transceiver 616 may also represent a separate transmitter and receivers. The radio-frequency coil 614 may also have multiple receive/transmit elements and the radio frequency transceiver 616 may have multiple receive/transmit channels. For example if a parallel imaging technique such as SENSE is performed, the radio-frequency could 614 will have multiple coil elements.

[0096] In this example the subject, 102 is positioned such that the subject's head region is within the region of interest 609 so that measurements on the brain can be made.

[0097] The stimulus presentation system 108, the activity measurement system 106, the transceiver 616, and the gradient controller 612 are shown as being connected to a hardware interface 122 of the computer system 118. The memory 130 is further shown as containing pulse sequence commands 620. The pulse sequence commands enable the processor 120 to acquire magnetic resonance data 622 according to a magnetic resonance imaging protocol. The magnetic resonance imaging protocol may be selected so that it is able to measure brain activity of the subject 102 directly.

[0098] For example, the magnetic resonance imaging protocol could be selected so that the so-called BOLD response is measured in real time using functional magnetic resonance imaging. The memory 130 is shown as containing magnetic resonance data 622 that was acquired by executing the pulse sequence commands 620. The memory 130 is further shown as containing a magnetic resonance image 624 that was reconstructed from the magnetic resonance data 622. The magnetic resonance image 624 could for example show the brain activity of the subject 102 at different periods of time. The memory 130 is further shown as containing EEG data 626 that was acquired using the EEG system 401. The magnetic resonance image 624 and the EEG data 626 could be used to provide the brain activity data 138.

[0099] Neurofeedback training is a promising approach for treating a large variety of psychiatric diseases/disorders, e.g. ADHD, ADD, depression, autism, anxiety disorders, bipolar disorders, dementia, and many more. Besides treating diseases/disorders, neurofeedback training can also improve the cognitive performance of healthy subjects. During a training session, the patient's brain activity is constantly monitored in real-time using, e.g., fMRI, EEG or MEG. The patient tries to reach a desired state of mind, e.g., happiness or focus. When this desired pattern of brain activity is reached, a visual, auditory or tactile reward/reinforcer (the feedback) is presented to the patient. After repeated training (typically >10 sessions) the patient is supposed to be able to reach the desired state of mind without the feedback signal.

[0100] A current problem of neurofeedback training is that the reinforcers (sensory stimuli) are not selected individually. Thus, they lack specificity with respect to subject and disease specific characteristics. For example, indications were found that learning-disabled children benefit more from auditory than from visual reinforcers while in clinical practice, typically visual reinforcers are used.

[0101] Examples may provide for a system, which is capable of selecting the optimal reinforcer (chosen element from a stimulus reinforce database) in a patient (subject) and/or disease specific manner. The system may comprise a database (stimulus reinforce database 134) of possible stimuli, an apparatus, which can present the stimuli to the patient, and a measurement device (activity measurement system 106), which measures the patient's response to the different stimuli (brain activity 138). Finally, an algorithm chooses the optimum stimuli (choice of the chosen entry 140) based on the measurement results and based on a priori knowledge with respect to patient and/or disease specific characteristics, after a sufficient amount of data exists.

[0102] First, a database of possible stimuli is provided. Possible stimuli are of

[0103] visual (e.g., pictures and videos of various objects and with variable degree of detail etc.),

[0104] auditory (ranging from simple sinus tones to various noises to complex music) and

[0105] tactile (e.g., synthetic jets)

nature or combinations thereof. In one embodiment, the stimulus database is provided on a computer.
Second, a system (stimulus presentation system) which is capable of presenting the stimulus to the patient is provided.

[0106] In one example, visual and auditory stimuli are provided to the patient using a screen and headphones.

[0107] In another example, the stimuli are presented in a virtual reality environment to the patient.

[0108] In another example tactile stimuli can be provided both manually (by, e.g., a practitioner who gets informed when the stimulus is to be applied and which stimulus has to be provided) or automatically by, e.g., computer-controlled devices such as synthetic jets, systems which can provide heat/cold, or mechanical systems which can, e.g. poke the patient.

[0109] In another example, multisensory combinations of stimuli are employed. To be more precise: it is known from literature that multisensory rhythmically synchronous signals create a synergetic attentional capture effect across the used senses (1+1>2), while multisensory non-synchronous signals are perceived as annoying. The attentional capture of synchronous multisensory signals helps the patient to keep focusing on the task at hand for neurofeedback. In this embodiment one must be particularly careful that the periods of the stimuli that are to be combined are identical (the deviation should be within the order of milliseconds after a ten-minutes trial run), which can be ensured by using one single signal generating apparatus that is connected to the stimuli generating apparatuses (earphones, screen, tactile device etc.).

[0110] In another example, the participant is exposed to the neurofeedback stimuli after lowering the breathing rate using device-guided breathing to help the patient to keep focused attention on the exposed stimuli. It is known from literature that that a lower breathing rate during exposure training facilitates the capability of the patient to undergo effective exposure. With lower breathing rate a patient experiences a greater sense of control and thereby facilitating the positive outcome effect of the exposure and the combined neurofeedback. Lower breathing rate is believed to reduce the arousal level and excitability of sympathetic fight-flight behaviors.

[0111] The system may also comprise a measurement system (an activity measurement system), which is capable of measuring the patient's response to those stimuli, is provided. Possible modalities include EEG, MEG and fMRI. Possible observables are magnitudes and timings of event related potentials (fields) in EEG (MEG) or BOLD response (fMRI).

[0112] In one example, the response of the brain's region of interest for the neurofeedback is being recorded.

[0113] In another example neural activity from the amygdala is being recorded (e.g., the BOLD response in real-time fMRI). It is known from literature that the amygdala reflects the emotional (and mood) state associated with the stimulus signal.

[0114] In another example, the relative ratio of brain waves (relative power of frequency bands in EEG or MEG) or connectivity patterns (EEG/MEG/fMRI) or other derived quantities are recorded.

[0115] In another example, not only the patient's physiological response to the stimulus but also the subsequent task performance (e.g. keeping focus, reaction tests) is recorded.

[0116] The system may also comprise, an algorithm (machine executable instructions), possibly an autonomously learning artificial intelligent agent(possibly implemented using a convolutional neural network), is used to select the optimal stimulus.

[0117] In one example the optimal stimulus is determined in a calibration session preceding the first training session. During this session, various stimuli are presented to the patient, while the patient's response to those stimuli is constantly monitored as described above. Then, the stimulus with, e.g., the

[0118] strongest response (e.g., largest amplitude of ERP, ERF or BOLD response),

[0119] fastest response,

[0120] best subsequent task performance and/or

[0121] desired change of connectivity patterns

or combinations thereof is chosen for the subsequent training session.

[0122] In one example, it is first determined whether a visual, auditory or tactile stimulus or a combination thereof is most suitable and then the most suitable stimulus out of this subset is found.

[0123] In another example, the response to the stimulus is also monitored during the training sessions and can be changed online, e.g., in the case of wear-out-effects. Then either a new calibration session is performed, or the second-best stimulus is chosen, or a new stimulus based on the results of the first calibration session and, e.g., a neighborhood-classifier which selects similar stimuli, is chosen. For example, an image classification algorithm could select similar images. The selection algorithm can also be trained to select suitable stimuli for new patients based on a recommendation engine, without the need of a prior calibration session.

[0124] In one example, this algorithm takes into account the diagnosis and patient specific characteristics (e.g., age, gender) and has been trained with results of calibration sessions and training outcomes of similar patients.

[0125] FIG. 7 illustrates an example of a functional implementation of a computer system 118 that is able to generate the chosen entries 140 for performing neurofeedback training. In the example there is a calibration session 700 and then a neurofeedback training session 702. The calibration session 700 is divided into a simulation phase, a measurement phase and an optimization phase 708. The neurofeedback training session optionally has also an optimization phase 708, has a reinforcer reward portion 710 that comprises the neurofeedback training and optionally a measurement phase 712 again. For example new measurements during the measurement phase 712 may be used for further optimization and selection of the chosen entry 140. During the simulation phase 704 the stimulus reinforcer database 134 is used to select the set of entries 136. Then the measurements 706 are performed using the activity measurement system 106. This results in the acquisition of the brain activity data 138. An algorithm 132 is then used to optimize this and select the chosen entries 140 which are used to make the modified neurofeedback training instructions.

[0126] In the example of FIG. 7, a variety of different stimuli is presented one after another to the patient (e.g., using a screen and headphones for auditory, visual and multisensory (audio+video) stimuli). After each stimulus presentation, a real-time fMRI measurement reveals the BOLD response at the amygdala, which reflects the emotional state associated with the stimulus signal. The larger the BOLD response, the stronger the stimulus effects the emotional state of the subject. The results (the BOLD response amplitude) are stored and, e.g., sorted by the BOLD response amplitude at the amygdala. For the subsequent neurofeedback training session, initially the stimulus with the larges BOLD response (here: stimulus #2) is chosen by the optimization algorithm. In this example embodiment, the BOLD response at the amygdala is measured via real-time fMRI also during the training session. With time, the response to the stimulus may decrease due to wear-out effects. Once the response has gotten weaker than the response of the second strongest stimulus (here: stimulus #1), the second strongest stimulus is selected for the subsequent task(s). Note that this online optimization during the training session is optional. Also note that the optimization algorithm can optionally be used already during the calibration session for optimizing the selection process. This can be done by, e.g., classifying the available stimuli and proposing the most promising stimuli, after a certain amount of data was collected. E.g., when it is found that the patient apparently responds stronger to detailed photographs compared to abstract patterns, then subsequently more detailed photographs and fewer abstract patterns are shown. This classification could be done manually or by means of an image classification algorithm.

[0127] FIG. 8 illustrates an example of an animation 800 of a thermometer. The animation of the thermometer 800 may use different temperatures to indicate different states as measured by the neurofeedback training.

[0128] FIG. 9 shows an animation of an expanding and/or contracting sphere 900. This also may be used as a visual neurofeedback stimulus.

[0129] FIG. 10 shows an animation of a flying bird 1000. The position or height of the bird 1000 may for example be used as feedback for neurofeedback training.

[0130] FIG. 11 illustrates a number of rewards which can be presented to a subject during neurofeedback training. For example, FIG. 11 shows a geometric pattern reward 1100 that may be displayed to the subject. FIG. 11 also shows an alternative geometric pattern reward 1102 that may be displayed to the subject. FIG. 11 further illustrates a star reward image 1104 that may be presented to the subject as a reward. FIG. 11 further shows a bird reward image 1106 that may be presented to the subject as a reward. FIG. 11 further illustrates an image of an automobile or car 1108 which may be presented to the subject as a reward. FIG. 11 further shows a representation of a sinusoidal tone 1110 which may be an audible tone reward 1110 that is presented to the subject. Item 1112 represents an audible melody reward 1112 that may also be presented to the subject. The items illustrated in FIGS. 8, 9, 10, and 11 may all be inputted in the set of entries 136 that is tested by measuring the brain activity data 138.

[0131] FIG. 12 illustrates an example of a visual breathing indicator 1200. The visual breathing indicator 1200 shows an animation of an expanding and contracting circle over time the size of the circle is intended to indicate the breathing phase of the subject.

[0132] FIG. 13 illustrates an example of an audible breathing indicator 1300. In this case the tone of a sinusoidal tone or other tone is varied as a function of time to indicate the breathing phase of the subject. For example, as the subject inhales the frequency may either increase or decrease.

[0133] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments.

[0134] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be construed as limiting the scope.

LIST OF REFERENCE NUMERALS

[0135] 100 medical instrument [0136] 102 subject [0137] 104 subject support [0138] 106 activity measurement system [0139] 108 stimulus presentation system [0140] 110 virtual reality goggles [0141] 112 headphones [0142] 114 body temperature control system [0143] 116 tactile feedback system [0144] 118 computer [0145] 120 processor [0146] 122 hardware interface [0147] 124 user interface [0148] 130 memory [0149] 132 machine executable instructions [0150] 134 stimulus reinforcer database [0151] 136 set of entries [0152] 138 brain activity data [0153] 140 chosen entry [0154] 142 neurofeedback training instructions [0155] 144 modified neurofeedback training instructions [0156] 200 control the stimulus presentation system with a set of entries from the stimulus reinforcer database to repeatedly provide sensory stimulus to the subject [0157] 202 control the activity measurement system for performing the measurement of the brain activity data during each sensor stimulus [0158] 204 select a chosen entry from the set of entries using the brain activity data [0159] 206 store the chosen entry in the memory [0160] 300 receive neurofeedback training instructions [0161] 302 modify the neurofeedback training instructions by incorporating commands from the chosen entry [0162] 304 control the stimulus presentation system with the modified neurofeedback training instructions [0163] 400 medical instrument [0164] 401 EEG system [0165] 500 medical instrument [0166] 502 respiration belt (respiration measurement system) [0167] 504 respiration indicator entries [0168] 506 respiration data [0169] 508 chosen respiration indicator [0170] 600 medical instrument [0171] 602 magnetic resonance imaging system [0172] 604 magnet [0173] 606 bore of magnet [0174] 608 imaging zone [0175] 609 region of interest [0176] 610 magnetic field gradient coils [0177] 612 magnetic field gradient coil power supply [0178] 614 radio-frequency coil [0179] 616 transceiver [0180] 620 pulse sequence commands [0181] 622 magnetic resonance data [0182] 624 magnetic resonance image [0183] 626 EEG data [0184] 700 calibration session [0185] 702 neurfeedback training session [0186] 704 simulation [0187] 706 measurement [0188] 708 optimiation [0189] 710 Reinforcer/Reward [0190] 712 Measurement [0191] 800 thermometer animation [0192] 900 expanding/contracting sphere animation [0193] 1000 flying bird animation [0194] 1100 geometric pattern reward image [0195] 1102 geometric pattern reward image [0196] 1104 star reward image [0197] 1106 bird reward image [0198] 1108 car image reward [0199] 1110 audible sinusoidal tone reward [0200] 1112 audible melody reward [0201] 1200 visual breathing indicator [0202] 1300 audible breathing indicator