Attachment 1 MRI Compatible Behavioral Testing Equipment Suite Narrative Specifications.pdf

MRI Compatible Behavioral Testing Equipment Suite Narrative Specifications

The system must be a modular, multi-channel platform that records physiological signals from human research participants continuously and simultaneously on a shared timebase. It must be suitable for use both in a standalone laboratory setting and inside the MRI environment, and MRI compatibility is a required characteristic rather than an option. At minimum it must acquire electrocardiogram (ECG), surface electromyogram (EMG), electrodermal activity (EDA), and respiration. It must also support additional measures through interchangeable modules or transducers, including pulse/photoplethysmography, peripheral oxygen saturation (SpO2), and skin temperature. The system must be expandable so that channels and signal types can be added without replacing the base unit, and it must provide at least sixteen analog input channels as delivered.

The system must be MR-conditional and safe for recording from participants inside the scanner. It must use non-ferromagnetic electrodes, leads, and in-bore components with appropriate current-limiting safety features. It must provide RF filtering and shielded or fiber-optic signal transmission so that the equipment does not degrade image quality and the scanner does not corrupt the physiological signal, and it must be rated as MR-conditional up to the field strength of the scanner in use. The same system must remain fully usable outside the scanner for standalone laboratory recording without additional major equipment.

The system must digitize all signals at sixteen-bit resolution or greater. It must sample each signal at a rate sufficient to capture the relevant frequency content of that measure, and it must provide higher sampling rates for electromyography, which contains higher-frequency content than the other signals.

All amplifier inputs connected to participants must be electrically isolated and must meet a recognized human-subject electrical-safety standard such as IEC 60601-1. The amplifiers must have a low noise floor and a common-mode rejection ratio of at least 100 dB so that low-amplitude signals record cleanly.

For cardiac measurement, the system must record the ECG waveform with enough bandwidth and fidelity to detect R-waves reliably and to derive heart rate and heart-rate variability, with configurable gain and band-pass filtering. For muscle activity, it must record surface EMG across a bandwidth of at least roughly 10 Hz to 500 Hz, with configurable filtering suitable for both large-muscle recordings and low-amplitude facial or startle EMG. For electrodermal activity, it must measure skin conductance using a DC-coupled, constant-voltage method reported in microsiemens, resolving both the tonic skin-conductance level and phasic responses. For respiration, it must record respiratory effort using a piezoelectric or pneumatic belt transducer.

The system must integrate with the rest of the experimental setup. It must accept digital or TTL event markers so that stimulus onsets and experimental events are recorded on the same timebase as the physiological data, and it must accept an external trigger from stimulus-presentation software and from the MRI scanner, such as a per-volume TR pulse. All synchronization inputs and outputs must be documented, including connector types and signal levels, so that integration with existing laboratory equipment can be verified.

The system must include acquisition and analysis software with real-time multi-channel display, event marking, and offline review. Recorded data must export to open, non-proprietary formats such as EDF, delimited text, or MATLAB-readable files. The delivered system must include the electrodes, leads, transducers, respiration belts, and starter consumables needed to begin all specified measurements, along with user documentation, calibration procedures, and a parts list of recurring consumables.

Delivery: 4301 Jones Bridge Road, Bethesda, MD 20814