Finger motion sensors for fMRI motor studies

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Motor task performance kinematics influence brain activity.
• Limited availability of MRI-compatible devices hinders on-line kinematic recording in functional magnetic resonance imaging (fMRI) motor studies.
• Accurate kinematic data is crucial for understanding brain-movement relationships.

Purpose of the Study:

• To develop and validate a Micro-Electro-Mechanical System (MEMS) gyroscope-based device for measuring finger kinematics during fMRI.
• To assess the device's compatibility with the MRI environment and its impact on image quality and statistical activation maps.
• To demonstrate the device's utility in exploring the relationship between finger movement kinematics and brain activation.

Main Methods:

• Fabrication of a MEMS gyroscope device to measure angular velocity of finger segments during fMRI.
• Computation of finger position, acceleration, and jerk from angular velocity data.
• Evaluation of sensor signal-to-noise ratio (SNR), stability, and impact of radiofrequency (RF) noise and magnetic fields.

Main Results:

• The MEMS device accurately measured finger kinematics with good signal-to-noise ratio (SNR) and stability during fMRI.
• The device showed negligible RF noise increase and did not cause MR image artifacts or alter fMRI activation maps.
• Sensor performance was robust in a 3 Tesla (T) magnetic field, with acceptable SNR reduction under higher RF power.

Conclusions:

• The developed MEMS gyroscope device is a viable tool for on-line kinematic acquisition during fMRI motor tasks.
• This technology enables more detailed investigation of the interplay between movement kinematics and brain activation in both healthy and injured brains.
• The device facilitates a deeper understanding of motor control and neurological conditions through precise kinematic-fMRI correlation.