A novel low-noise movement tracking system with real-time analog output for closed-loop experiments

Area of Science:

• Neuroscience
• Biophysics
• Systems Biology

Background:

• Electrophysiological experiments increasingly require real-time feedback loops.
• Accurate monitoring of rodent 2D kinematics is crucial for spatial behavior studies.
• Existing camera-based tracking systems lack sufficient temporal resolution for precise real-time feedback.

Purpose of the Study:

• To develop a novel software and hardware system for real-time 2D movement tracking.
• To provide low-noise analog outputs of kinematic features for closed-loop experiments.
• To enable precise real-time feedback in rodent behavioral studies.

Main Methods:

• A novel system using color-markers for movement tracking.
• Real-time processing of 2D kinematic data including position and orientation.
• Utilized adaptive windowing, contour extraction, and Kalman filtering for robust tracking.

Main Results:

• The system processes frames in 28ms with minimal jitter, achieving 100 frames per second.
• Provides low-noise, smooth, and accurate analog outputs of movement features.
• Demonstrated applications in replacing conventional sensors and closed-loop optogenetic stimulation.

Conclusions:

• This is the first real-time tracking system with analog output.
• The modular system is open-source and uses low-cost hardware.
• Facilitates advanced closed-loop experiments in neuroscience research.