A multimodal monitoring platform for animal physiology and behavior during intravital brain imaging

Optical imaging in awake rodents offers powerful, nondisruptive methods to characterize brain function and energy metabolism with high spatial and temporal resolution. However, detailed investigations are often confounded by variations in the animals’ alertness and stress levels, as well as spontaneous motion artifacts. To facilitate 2-photon microscopy and widefield optical imaging experiments in awake mice, we developed a centralized integrated device for real-time monitoring of physiology and detection of spontaneous motion artifacts. Our compact and low-cost device provides wellsynchronized, complementary measurements of the mouse’s pupil diameter and animal behavior during imaging experiments. The device is comprised of a centralized, portable data acquisition system and a customized animal positioning frame. The data acquisition system, based on a powerful microcomputer, monitors movement through one camera and a custom-designed accelerometer and records pupil diameter through another custom camera. To validate performance, our device was utilized during wide-field optical imaging experiments exploring functional brain activation. The results demonstrated that the device substantially reduces experimental setup time while effectively screening motionaffected trials. We also observed a robust correlation between brain activity and pupillary change in response to functional somatosensory activation. The results indicate that our device is a promising tool to monitor auxiliary readouts of brain activity while also streamlining optical imaging studies.