The Most Advanced MEG System in The World
No SQUID re-tuning, no flux jumps
MEG by CTF
The Hardware
The MEG systems from CTF deliver the highest signal to noise ratio (SNR) MEG data of any commercially available magnetoencephalography. The sensor array is composed of 151 or 275 axial gradiometer MEG sensors distributed over the whole cortex (cMEG) or abdominal region (fMEG) with additional reference channels used for noise cancellation.
EEG, EOG/EMG, ADC/DAC, and triggers accompany this design to allow synchronous activation and recording of a wide range of stimulus instruments and physical response monitors.
All channels may be used simultaneously and are managed by a common hardware interface, a signal processing unit, and a Linux based acquisition computer. An analysis computer is included, allowing simultaneous collection and data processing. All computers are equipped to run the full complement of CTF MEG advanced processing and analysis software.
The system includes subject stimulation and response equipment for auditory, visual, electric, and/or tactile experiments. The CTF MEG consistently delivers clean signals, reliable operation, accurate localizations of brain function, and future expandability.
CTF MEG Sensors: Key Benefits
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Shielded SQUIDs with Nb wire pickup loops
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Stable operation: no SQUID retuning, no flux jumps.
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Operate in high fields. Axial gradiometer MEG sensors
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High sensor density (22 mm spacing in a 275 system).
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Easy to interpret and plot data.
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Electronics: High bandwidth, slew rate, sample rate
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Easy to record auxiliary data outside MEG band.
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Huge dynamic range.
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Low electronics delay for real-time MEG.
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Interference suppression: Uses reference sensors
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Responds to external interference like a 3rd gradiometer.
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Does not mix the brain signals in different channels.
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Full-rank covariance matrix.
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Data Acquisition system: Reliable stable Linux-based software
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Displays filtered, interference-suppressed MEG data in real time.
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Stores data at up to 19,200 samples/s.
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User friendly and easy to run.
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Real-time MEG: Electronics delay is 0.3 micro seconds.
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Real-time delay is due to the user-supplied MEG-analysis system.
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No delay jitter.
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Continuous Head
Localization:
Measures head position up to 30 times per sec.
Does not interfere with collection or real-time display of MEG data. Active shielding: Not needed with CTF's robust pickup loops, SQUIDs and electronics. We do not recommend active shielding as a way to reduce the cost of a MEG system.
The Software
CTF MEG acquisition and analysis software is specifically designed to provide a complete work environment for MEG/EEG studies. The software is designed to maximize laboratory productivity as well as offer the user complete flexibility in workflow. CTF MEG applications provide intuitive graphical interfaces as well as powerful command-line functions for automated procedures.
Features include:
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Control of CTF MEG electronics for tuning, calibration, and acquisition.
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Rapid data processing and quality assessment, including a wide range of time, frequency and spatial filtering options.
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Automatic and manual marking of key time points and classification of trials.
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Data averaging across time and subjects.
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Source modeling methods to interpret the data as one or more equivalent current dipoles (ECDs).
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Synthetic Aperture Magnetometry (SAM), allowing for probability current density mapping, time display of arbitrarily positioned and arbitrary number of virtual depth electrodes, Statistical Parametric Mapping (SPM/SAM), and Differential Statistical Parametric Mapping (differentiating between cognitive states).
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Overlay of MEG/EEG data with MRI to provide relationship between brain anatomy and brain function.
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Importation of head shape data.
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Powerful scripting for batch processing.
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User access to the CTF MEG data format, with library routines for importing CTF MEG data into user written routines and other computer platforms.
All application software source code available under Non-Disclosure-Agreement.