Automated video-based heart rate tracking for the anesthetized and behaving monkey

Area of Science:

• Primate behavior and physiology
• Biomedical engineering
• Neuroscience

Background:

• Heart rate (HR) is crucial for studying primate behavior and physiology.
• Current methods for HR collection in non-human primates are often invasive or require extensive training.
• Eulerian video magnification (EVM) is an established technique for HR extraction in humans.

Purpose of the Study:

• To adapt and validate the Eulerian video magnification (EVM) method for non-invasive heart rate tracking in macaques.
• To assess the accuracy and resilience of the EVM method in both anesthetized and awake, behaving macaques.
• To establish EVM as a versatile tool for ethological, behavioral, neuroscience, and welfare research in non-human primates.

Main Methods:

• Implementation of Eulerian video magnification (EVM) combined with wavelet transform for heart rate tracking.
• Utilized image-to-image fluctuations in skin reflectance due to blood flow changes.
• Collected data from both color (RGB) and infrared (IR) videos of macaques.

Main Results:

• Demonstrated strong temporal coherence and amplitude matching between EVM-derived HR and electrocardiogram (ECG) in anesthetized macaques.
• Successfully identified consistent HR changes in response to conspecific emotional stimuli (voices and faces).
• Showcased the method's resilience to head motion in awake, behaving macaques, outperforming traditional video photoplethysmography.

Conclusions:

• The EVM heart tracking method provides a non-invasive, accurate, and robust approach for measuring macaque heart rate.
• This technique is applicable to both anesthetized and awake, behaving macaques, offering significant advantages over existing methods.
• EVM is a promising tool for advancing research in primate behavior, neuroscience, and welfare.