Portable magnetoencephalography system with hybrid quantum magnetometers and motion-sensitive active field control

Abstract

A portable magnetoencephalography (MEG) system (100) for non-invasive recording of magnetic fields of the brain during natural behaviors, the system (100) comprising: an adaptable non-ferromagnetic helmet (1) configured to be worn on the head of a test subject; a plurality of interchangeable sensor capsules (2) attached to the helmet (1), each sensor capsule (2) comprising: a triaxial quantum magnetometer (3) in the form of an optically pumped magnetometer configured to measure magnetic fields along three orthogonal axes, and a local inertial measurement unit (IMU) (4) configured to provide motion signals with six degrees of freedom; at least one additional IMU (5) attached to the helmet (1) and configured to measure head movements; an active field control subsystem (6) comprising a plurality of magnetic field generating coils (7) embedded in the helmet (1) and at least one reference quantum magnetometer (8) positioned to detect magnetic fields in the environment; an external electronic module (9) containing at least one clock generator (25), at least one digital processor (26), at least one power supply circuit and a wireless communication interface (19); a weak magnetic connection (10) between the sensor capsules (2) and the external electronics module (9), wherein the weak magnetic connection (10) comprises at least one optical wiring and / or one non-ferromagnetic electrical wiring; and a control unit (11) that is connected to the sensor capsules (2), the reference quantum magnetometer (8), the IMUs (4, 5), the active field control subsystem (6) and the external electronics module (9), wherein the helmet (1) and the sensor capsules (2) are configured to maintain a sensor-to-scalp distance of less than or equal to 10 mm over a range of head sizes, and the control unit (11) is configured that they: (i) to synchronize the magnetometer signals from the triaxial quantum magnetometers (3) and the IMU signals from the IMUs (4, 5) with a synchronization error of no more than 0.5 ms, (ii) continuous updating of the conduction fields that map the brain sources to the sensor capsules (2) based on the IMU signals from the IMUs (4, 5), and (iii) to reconstruct the magnetic activity of the brain in real time using the updated conduction fields while the test subject performs voluntary movements.

Description

INVENTION AREA

[0001] The present invention relates to non-invasive neuroimaging. In particular, the invention relates to a portable magnetoencephalography (MEG) system (100) based on quantum magnetometers, configured to record magnetic fields of the brain in natural environments with improved motion tolerance, safety, and scalability for clinical and research use.

[0002] In particular, the present invention relates to a portable magnetoencephalography system with hybrid quantum magnetometers and motion-aware active field control. BACKGROUND OF THE INVENTION

[0003] The subject matter discussed in the "Background" section should not be considered prior art solely because it is mentioned in that section. Likewise, a problem mentioned in the "Background" section or related to the subject matter of the "Background" section should not be considered prior art. The subject matter in the "Background" section merely presents various approaches, which could themselves also be inventions.

[0004] Magnetoencephalography (MEG) is a functional neuroimaging technique that detects very small magnetic fields generated by synchronous postsynaptic currents in cortical neurons. MEG offers millisecond-level temporal resolution and, compared to electroencephalography (EEG), improved accuracy in source localization because the magnetic fields are less distorted by the skull and scalp.

[0005] Conventional clinical MEG systems are based on superconducting quantum interference devices (SQUIDs) housed in cryogenic Dewars. The SQUIDs are mounted in a rigid helmet located within a magnetically shielded room (MSR). While such systems offer very high sensitivity, they have several drawbacks: • High costs and infrastructure: The cryogenic cooling system, helium handling, and magnetically shielded room significantly increase capital and operating costs. • Rigid sensor geometry: The distance between the sensor and the scalp is determined by the thickness of the Dewar stencil. This reduces signal strength and spatial resolution, especially in small heads, such as those of pediatric subjects. • Limited motion tolerance: Even small head movements relative to the rigid sensor array can cause localization errors and artifacts, making it difficult to perform recordings during natural behaviors. • Limited accessibility: The bulky infrastructure and restricted freedom of movement make it difficult or impossible to use the device at the bedside, in outpatient facilities, or in environments with limited resources.

[0006] Recent developments in optically pumped magnetometers (OPMs) and similar quantum magnetometers enable MEG to be performed without cryogenics. Alkaline vapor OPMs operating in spin-exchange relaxation-free (SERF) mode can achieve sensitivity comparable to SQUIDs. However, alkaline vapor OPMs typically require heating to maintain vapor density and perform best in very weak ambient magnetic fields. This complicates long or mobile recordings, especially when head movements alter the magnetic environment.

[0007] Helium-4 ( 4 He)-OPMs offer an alternative with higher bandwidth and greater dynamic range and do not require heaters, but must be integrated into a system that can handle magnetic drift, head movement and electronic noise.

[0008] Three major challenges hinder the use of MEG outside of traditional shielded spaces: • Environmental magnetic drift: Fluctuations in the Earth's magnetic field and nearby ferromagnetic objects shift the operating points of the sensors and can lead to sensor saturation during movement. • Head movement: Changes in head position relative to the sensors alter the mapping between brain sources and measurements; without real-time correction, this leads to localization errors. • Electronic interference: Power supply systems, clocks, digital processors and communication interfaces cause low-frequency and high-frequency interference that distorts the MEG signals.

[0009] Existing OPM-based MEG prototypes typically address only some of these problems. Many solutions rely on external, space-filling biplanar coils for field control, leave significant electronics close to the sensors, or fail to fully integrate motion sensing into the source reconstruction. Therefore, there is a need for a fully portable MEG platform that combines the following: • Flexible placement of the sensors near the scalp; • an integrated active field control that moves with the head; • Distributed motion sensors and motion-aware reconstruction; and • a magnetically quiet electronic architecture with off-head processing.

[0010] As used in the present description and in the following claims, the meaning of "a", "an", and "the" also includes the plural unless the context clearly requires otherwise. As used in the present description, the meaning of "in" also includes "in" and "on" unless the context clearly requires otherwise.

[0011] The use of value ranges in this description serves only as a shorthand way to refer to each individual value within the range. Unless otherwise stated herein, each individual value is included in the description as if it were listed separately.

[0012] The use of examples or illustrative phrases (e.g., "such as") in relation to certain embodiments in this description serves only to better illustrate the invention and does not constitute a limitation of the otherwise claimed scope of the invention. No phrase in the description is to be interpreted as referring to an unclaimed element that is essential for carrying out the invention.

[0013] The information disclosed above in this "Background" section is provided solely for a better understanding of the background of the invention and may therefore contain information that is not part of the prior art already known to a person skilled in the art in this country. SUMMARY

[0014] Before describing the systems and methods presented here, it should be noted that this application is not limited to the specific systems and methods described, as there may be several possible embodiments not expressly presented in this disclosure. It should also be noted that the terminology used in the description serves only to describe the specific versions or embodiments and is not intended to limit the scope of this application.

[0015] In one aspect, the invention provides a portable magnetoencephalography (MEG) system (100). The system (100) comprises an adaptable non-ferromagnetic helmet (1) configured to be worn on a person's head. A plurality of interchangeable sensor capsules (2) are mounted on the helmet (1). Each sensor unit (2) houses a triaxial quantum magnetometer (3) in the form of an optically pumped magnetometer configured to measure magnetic fields along three orthogonal axes, and a local inertial measurement unit (IMU) (4) configured to provide motion signals with six degrees of freedom. At least one additional helmet-mounted IMU (5) is provided on the helmet (1) to capture the entire head movement.

[0016] The system (100) further comprises an active field control subsystem (6) provided on the helmet (1). The active field control subsystem (6) includes a plurality of magnetic field-generating coils (7) embedded in or on the helmet (1) and at least one reference quantum magnetometer (8) positioned to detect ambient magnetic fields and gradients around the head. An external electronics module (9) is connected to the helmet (1) and includes at least one highly stable clock (25), at least one digital processor (26), at least one power supply circuit, and a wireless communication interface (19), and may additionally or alternatively include a control unit (11). A weak magnetic connection (10) consisting of optical cables and / or non-ferromagnetic electrical cables connects the helmet (1) and the sensor capsules (2) to the external electronics module (9).

[0017] The helmet (1) and the sensor capsules (2) are mechanically arranged such that, when the system (100) is worn, the triaxial quantum magnetometers (3) are held at a distance of less than or equal to 10 mm between the sensor and the scalp across a range of head sizes. The controller (11) is configured to temporally synchronize the magnetometer signals of the triaxial quantum magnetometers (3) with the IMU signals of the IMUs (4, 5) with a synchronization error of no more than 0.5 ms. Using the synchronized motion information, the controller (11) continuously updates the conduction fields that map the brain sources to the sensor capsules (2) and reconstructs the brain's magnetic activity in real time as the test subject performs voluntary movements.

[0018] In preferred embodiments, the sensor capsules (2) are connectable to a hybrid quantum interface (12) configured to accept both optically pumped spin-exchange relaxation (SERF) magnetometers for alkali vapors and optically pumped magnetometers for helium-4. The control unit (11) is designed to automatically detect the sensor type used in each sensor module (2) and, based on the detected type, configure a heating control (13) for alkali vapor cells, a bandwidth setting module (14), and a dynamic range setting module (15). In this way, alkali vapor sensors can be operated with direct current up to at least 1,000 Hz, while helium-4 sensors can be operated with direct current up to at least 2,000 Hz with corresponding sensitivity and dynamic range.

[0019] The active field control subsystem (6) works in conjunction with the motion sensor units to stabilize the operating point of the magnetometers. A Kalman filter (16) implemented by the controller (11) combines the outputs of the reference quantum magnetometer (8) and the IMUs (4, 5) to estimate quasi-static ambient magnetic fields and field gradients. The control unit (11) directs currents through the coils (7) built into the helmet to generate opposing fields that cancel out the estimated ambient fields and gradients, thereby keeping the triaxial quantum magnetometers (3) within their dynamic range during head movements and ambient drift, and reducing or eliminating the need for space-filling field compensation coils.

[0020] Each sensor unit (2) may further comprise a locally shielded analog front-end circuit (17) and at least one digitizer (18) configured to amplify, filter, and digitize the output signals of the three-axis quantum magnetometer (3). High-frequency clocks and high-current digital processors are physically separated from the sensor modules (2) in the off-head electronics module (9) to reduce magnetic interference at the helmet (1). The wireless communication interface (19) may use a frequency-agile wireless uplink (28) operating in a limited-emission mode to transmit aggregated data to an external computer device.The controller (11) can implement an adaptive real-time beamforming engine (20) that uses the synchronized magnetometer and IMU data together with environment estimates to generate band power maps, event-related fields and source-specific time series with an end-to-end latency of no more than 25 ms.

[0021] In certain embodiments, the system (100) also includes features to improve child safety and user comfort. Sensor capsules (2) containing alkaline vapor magnetometers are equipped with multi-layered thermal protection devices (31) and airflow deflectors (32) so that the skin contact surfaces remain below a predetermined safety temperature. For long-term studies or pediatric recordings, helium-4 capsules without heating devices may preferably be selected. The helmet (1) may also be equipped with ergonomic straps (29) and soft padding (30) to improve positioning, safety, and comfort during extended recordings. BRIEF DESCRIPTION OF THE DRAWING

[0022] To clarify various aspects of some embodiments of the present invention, a more detailed description of the invention is given with reference to specific embodiments illustrated in the accompanying drawings. It is understood that these drawings represent only illustrated embodiments of the invention and are therefore not to be considered as limiting its scope. The invention is described and explained with additional specificity and detail using the accompanying drawings.

[0023] To make the advantages of the present invention easily understandable, a detailed description of the invention is given below in conjunction with the accompanying drawings, which, however, should not be regarded as limiting the scope of the invention to the accompanying drawings, in which: Fig. Figure 1 shows a schematic view of a portable MEG system (100) comprising the adaptable helmet (1), sensor capsules (2), IMUs (4, 5), an active field control subsystem (6), a low magnetization link (10) and an external electronics module (9). DETAILED DESCRIPTION

[0024] The present invention relates to a portable magnetoencephalography system (100) using hybrid quantum magnetometers and motion-aware active field control.

[0025] Fig. shows a detailed block diagram representation of a portable magnetoencephalography system (100) using hybrid quantum magnetometers and motion-aware active field control.

[0026] Although the present disclosure has been described with the purpose of a portable magnetoencephalography system using hybrid quantum magnetometers and motion-aware active field control, it should be noted that this was merely to illustrate the invention by way of example and to highlight other purposes or functions for which the described structures or configurations could be used and which fall within the scope of the present disclosure.

[0027] The invention is now referred to as Fig. Figure 1 describes a schematic embodiment of a portable magnetoencephalography (MEG) system (100). For clarity, identical reference numerals denote identical parts in this description. It is understood that the drawing is not to scale and serves to explain the functional relationships between the components rather than to depict precise mechanical details.

[0028] As in Fig. As shown in Figure 1, the wearable MEG system (100) is configured to be worn on the head of a test subject and to record very small magnetic fields generated by neural activity in the brain, while the test subject can move freely and naturally. The system (100) comprises an adaptable non-ferromagnetic helmet (1) shaped to follow the general contour of the test subject's scalp. The helmet (1) is made of a material that does not significantly distort magnetic fields, for example, a plastic or composite material that is essentially free of ferromagnetic components.The geometry and thickness of the helmet (1) are chosen such that when the system (100) is correctly positioned on the head, the sensors contained in the helmet are less than or equal to 10 mm from the scalp, thereby improving the signal-to-noise ratio and spatial resolution compared to conventional MEG systems where the sensors are separated from the scalp by a thick cryogenic Dewar.

[0029] Several interchangeable sensor capsules (2) are attached to the helmet (1). Fig. Figure 1 shows several such sensor pods (2) distributed across the surface of the helmet (1); in operation, a set of 32 to 192 pods can be used, depending on the desired sensor density. Each sensor pod (2) is mechanically connected to the helmet (1) using non-ferromagnetic fasteners or mounts. The positions of the sensor pods (2) can be selected according to the size and shape of the test subject's head and the cortical regions of interest. The sensor pods (2) can be removable and reconfigurable to allow for different arrangements.

[0030] Each sensor pod (2) contains at least one triaxial quantum magnetometer (3) and a local inertial measurement unit (IMU) (4). For clarification, it contains Fig. 1 An enlarged inset showing a representative sensor pod (2) and its internal components. The three-axis quantum magnetometer (3) is implemented as an optically pumped magnetometer sensitive along three mutually orthogonal axes and configured to measure magnetic fields generated by brain activity. The local IMU (4) is a six-degree-of-freedom inertial sensor comprising accelerometers and gyroscopes, providing motion signals representing the orientation and linear acceleration of the corresponding pod (2). In preferred embodiments, each sensor unit (2) further includes a low-noise analog front end and a digitizer (in Fig. 1 not shown separately), to amplify, filter and digitize the output signals of the magnetometer (3) before transmission away from the head.

[0031] In addition to the local IMUs (4) within the sensor capsules (2), the helmet (1) has at least one helmet-mounted IMU (5). The helmet-mounted IMU (5) is located, for example, near the top of the helmet (1) and provides global information about the movement of the test subject's entire head. The output signals of the IMUs (4, 5) are used in combination to determine the position and orientation of each sensor module (2) relative to the test subject's head at any given time and to identify motion-related artifacts.

[0032] The system (100) further comprises an active field control subsystem (6) on or inside the helmet (1). As in Fig. As shown in Figure 1, the active field control subsystem (6) comprises a plurality of magnetic field-generating coils (7) embedded in the helmet structure and at least one reference quantum magnetometer (8) positioned on the helmet (1) but outside the main sensor array. The coils (7) can be configured as multiple turns following the curvature of the helmet (1) or as printed conductive traces; they are arranged such that the currents flowing through the coils (7) generate magnetic fields that counteract and thereby reduce the ambient fields in the region of the sensor capsules (2). The reference magnetometer (8) is configured to detect quasi-static ambient fields and gradients near the head but outside the main sensitivity range for brain signals. The coils (7) and the reference magnetometer (8) are in Fig. 1 shown and jointly identified as belonging to the active field control subsystem (6).

[0033] A weak magnetic connection (10) extends from the helmet (1) to an external electronic module (9). In Fig. Figure 1 schematically represents this connection (10) as a bundle of conductors running from the back of the helmet (1) downwards to the subject's body. The weak magnetic connection (10) consists of optical fibers and / or non-ferromagnetic electrical cables to minimize magnetic emissions and prevent interference with the sensors. The weak magnetic connection (10) transmits digitized measurement data, control signals, and power between the helmet (1) and the external electronics module (9).

[0034] The external electronics module (9) is designed to be worn outside the head, for example on a belt, at the waist or in a backpack, as in Fig. The external electronics module (9) contains a highly stable clock (25), one or more digital processors (26), and a control unit (11). In the illustrated embodiment, these elements are shown as separate blocks within the module (9) for clarity. The clock (25) provides a time base used to assign precise timestamps to the data arriving from the sensor capsules (2) and IMUs (4, 5). The processor (26) performs data aggregation, numerical calculations, and control algorithms. The controller (11) can be implemented as a dedicated circuit, as firmware executed by the processor (26), or as a combination of both; for the purposes of this description, these implementations are collectively referred to as the controller (11).

[0035] The controller (11) is connected via the weak magnetic link (10) and any intermediate circuits to the triaxial magnetometers (3), the IMUs (4, 5), the reference magnetometer (8), and the coils (7). Using the time base provided by the clock (25), the controller (11) synchronizes the magnetometer and IMU signals so that the relative time error between them does not exceed a predetermined limit, preferably no more than 0.5 milliseconds. Based on the synchronized IMU data, the controller (11) estimates in real time the orientation and position of each sensor pod (2) relative to the subject's head and an external reference frame. This information is used to update conduction fields that mathematically describe the mapping between neural current sources in the brain and the signals measured by each triaxial magnetometer (3).

[0036] The controller (11) also implements algorithms for reconstructing the brain's magnetic activity in real time using the updated recording fields. Such reconstruction may include, for example, beamforming, minimum norm estimation, or other inverse modeling techniques. Because the recording fields are continuously updated using IMU information, the reconstruction remains accurate even if the test subject moves their head or changes posture during the measurement. Motion-related artifacts caused by the movement of the sensors in the Earth's magnetic field can be identified and reduced by feedback components that correlate with IMU signals and the output signals of the reference magnetometer (8).

[0037] To keep the quantum magnetometers (3) within their usable dynamic range, the control unit (11) also operates the active field control subsystem (6). The control unit (11) receives measurements of the ambient field from the reference magnetometer (8) and, optionally, the head orientation derived from the IMU, and calculates estimates of the quasi-static ambient magnetic fields and gradients at the helmet (1). Based on these estimates, the control unit (11) drives currents through the coils (7) so that the fields generated by the coils (7) essentially cancel out the ambient components, thereby keeping the operating point of the triaxial magnetometers (3) close to their most sensitive range and reducing the risk of sensor saturation during movement or in the presence of magnetic drift in the environment.In preferred embodiments, the estimation and control are implemented using a Kalman filter or a similar state-space algorithm, although in . Fig. 1 such software modules are not shown separately.

[0038] The external electronics module (9) also includes a wireless communication interface (19). Fig. 1 This is symbolized by an antenna connected to the module (9). The wireless communication interface (19) is configured to transmit data and status information from the external electronics module (9) to an external computer, such as a base station computer, for further storage, visualization, or processing. To reduce interference with the sensitive magnetometers (3), the wireless interface (19) operates in a limited emission mode, for example, using a frequency-agile protocol and a correspondingly low transmit power, and is physically located away from the helmet (1).

[0039] Although in Fig. Figure 1 shows only the most important functional components; it will be clear to a person skilled in the art that additional circuits may be provided within the sensor capsules (2), within the helmet (1), or within the external electronics module (9) to perform power management, communication, safety monitoring, and user interface functions. Similarly, Figure 1 shows Fig. Although a single external module (9) is used, in some embodiments functions can be distributed between the external module and a separate external computer, or several modules can be used, without deviating from the scope of the invention as defined by the claims.

[0040] During operation, the test subject wears the helmet (1) with the sensor capsules (2) close to the scalp, while the external electronics module (9) is worn at the waist or on the back. The system (100) continuously acquires magnetic field data from the triaxial magnetometers (3) and motion data from the IMUs (4, 5). The controller (11) synchronizes these signals, actively stabilizes the magnetic environment using the coils (7) and the reference magnetometer (8), updates the conduction fields according to head movements, and reconstructs brain activity in real time. Because the heavy and noisy electronic components are not located on the head, and because ambient fields are locally blocked at the helmet (1), the system (100) enables high-resolution MEG recordings while allowing the test subject relatively free movement and eliminating the need for large cryo-Dewars or magnetically shielded rooms.

[0041] It goes without saying that the in Fig. The embodiment shown in Figure 1 is only one example of how the invention can be implemented. Variations can be made with regard to the number and arrangement of the sensor capsules (2), the construction of the helmet (1), the choice of quantum magnetometer technology, and the implementation of the control unit (11) and the wireless communication interface (19), while maintaining the scope of the appended claims.

[0042] The figure and the preceding description provide examples of embodiments. Those skilled in the art will recognize that one or more of the described elements can be combined to form a single functional element. Alternatively, certain elements can be divided into several functional elements. Elements from one embodiment can be added to another embodiment. For example, the sequence of the processes described here can be changed and is not limited to the manner described here. Furthermore, the actions in a block diagram need not be implemented in the order shown, nor does it necessarily have to be executed all actions. In addition, those actions that are not dependent on other actions can be executed in parallel with the other actions. The scope of execution is in no way limited by these specific examples.

[0043] Although the embodiments of the invention have been described in language relating to structural features and / or methods, it should be noted that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as examples of embodiments of the invention.

Claims

[1] A portable magnetoencephalography (MEG) system (100) for non-invasive recording of magnetic fields of the brain during natural behaviors, the system (100) comprising: an adaptable non-ferromagnetic helmet (1) configured to be worn on the head of a test subject; a plurality of interchangeable sensor capsules (2) attached to the helmet (1), each sensor capsule (2) comprising: a triaxial quantum magnetometer (3) in the form of an optically pumped magnetometer configured to measure magnetic fields along three orthogonal axes, and a local inertial measurement unit (IMU) (4) configured to provide motion signals with six degrees of freedom; at least one additional IMU (5) attached to the helmet (1) and configured to measure head movements; an active field control subsystem (6) comprising a plurality of magnetic field generating coils (7) embedded in the helmet (1) and at least one reference quantum magnetometer (8) positioned to detect magnetic fields in the environment; an external electronic module (9) containing at least one clock generator (25), at least one digital processor (26), at least one power supply circuit and a wireless communication interface (19); a weak magnetic connection (10) between the sensor capsules (2) and the external electronics module (9), wherein the weak magnetic connection (10) comprises at least one optical wiring and / or one non-ferromagnetic electrical wiring; and a control unit (11) that is connected to the sensor capsules (2), the reference quantum magnetometer (8), the IMUs (4, 5), the active field control subsystem (6) and the external electronics module (9), wherein the helmet (1) and the sensor capsules (2) are configured to maintain a sensor-to-scalp distance of less than or equal to 10 mm over a range of head sizes, and the control unit (11) is configured that they: (i) to synchronize the magnetometer signals from the triaxial quantum magnetometers (3) and the IMU signals from the IMUs (4, 5) with a synchronization error of no more than 0.5 ms, (ii) continuous updating of the conduction fields that map the brain sources to the sensor capsules (2) based on the IMU signals from the IMUs (4, 5), and (iii) to reconstruct the magnetic activity of the brain in real time using the updated conduction fields while the test subject performs voluntary movements. [2] System (100) according to claim 1, wherein the sensor capsules (2) are mounted on adjustable rails (22) of a modular helmet grid (21) comprising arc segments dimensioned to cover head circumferences of children and adults, and wherein positions and identities of the sensor capsules (2) are automatically logged by the control unit (11) to register them with anatomical image data. [3] System (100) according to one of the preceding claims, wherein the sensor capsules (2) can be connected to a hybrid quantum interface (12) configured to accept both optically pumped spin exchange relaxation (SERF) magnetometers without alkali vapor and optically pumped helium-4 magnetometers, wherein the control unit (11) is further configured to automatically detect a sensor type of each sensor module (2) and, based on the detected sensor type, to configure at least one of a heating control (13) for alkali vapor cells, a bandwidth setting module (14), and a dynamic range setting module (15), thereby enabling operation from DC up to at least 1,000 Hz for alkali vapor sensors and from DC up to at least 2,000 Hz for helium-4 sensors. [4] System (100) according to one of the preceding claims, wherein the active field control subsystem (6) is configured such that: the coils built into the helmet (7) generate opposing fields and the control unit (11) implements a Kalman filter (16) which combines the output signals of the reference quantum magnetometer (8) and the IMUs (4, 5) to estimate quasi-static ambient fields and magnetic field gradients and to control currents in the coils (7) built into the helmet, This ensures that the magnetometer operating points are maintained within a dynamic range of the sensor capsules (2) during head rotations and magnetic ambient drift, and enables operation in standard rooms or light-shielded rooms without dependence on room-sized biplanar coils. [5] System (100) according to any one of the preceding claims, wherein the IMUs (4, 5) on the helmet (1) and in the sensor capsules (2) are IMUs with six degrees of freedom, and the control unit (11) is further configured such that it: (i) to synchronize the IMU signals from the IMUs (4, 5) to a magnetometer reference clock (25), (ii) to estimate in real time a sensor-to-brain geometry of each sensor module (2) based on the IMU signals from the IMUs (4, 5), and (iii) To regress motion artifacts from the magnetometer signals of the triaxial quantum magnetometers (3) using the IMU signals from the IMUs (4, 5), so that the spatial localization of brain sources is maintained during natural movements, including steps and head turns. [6] System (100) according to one of the preceding claims, wherein the control unit (11) is further configured to implement a real-time adaptive beamforming engine (20) which: performs a channel-related noise estimation for each sensor unit (2), subtracting the environmental contributions estimated by the reference quantum magnetometer (8), the IMU-informed head posture and sensor posture from the IMUs (4, 5) are incorporated into source models and applies adaptive beamforming algorithms, including linearly constrained beamformers with minimal variance that are updated as a function of head position, to generate at least one of the following information: real-time band power maps, event-related field waveforms (ERF), and source-specific time series for display and archiving. [7] System (100) according to any one of the preceding claims, wherein: the sensor capsule density is configurable between 32 and 192 sensor capsules (2), with increased coverage over task-relevant cortical regions, the controller (11) is configured to perform a start-up calibration procedure (23) which includes measuring the sensor crosstalk and transfer functions of the coils (7) built into the helmet, and a pediatric mode (24) is provided in which the calibration procedure (23) is shortened using motion-robust standard parameters and a subset of the coils (7) and reference channels from the reference quantum magnetometer (8), thereby reducing the setup time and improving tolerance to motion in pediatric subjects. [8] System (100) according to any one of the preceding claims, wherein: Sensor pods (2) containing optically pumped alkaline vapor magnetometers, further comprising multilayer thermal protection devices (31) and airflow deflectors (32) configured to keep the skin contact surfaces below a predetermined safety temperature during operation, and Helium-4 optically pumped magnetometer capsules are configured to operate without heaters and can be selected by the control unit (11) as preferred sensors for pediatric or long-term studies, and the helmet (1) further comprises non-ferromagnetic ergonomic straps (29) and soft contact pads (30) configured to enhance safety and comfort during extended recordings.

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