PROJECT SUMMARY - ABSTRACT Following a highly successful Phase I, we will integrate closed-loop optogenetic capabilities into our fully implantable, wireless, battery-free, Mechano-Acoustic (MA) device. Additional antenna booster coil designs will increase cage power to the devices and allow larger open-field enclosures to be utilized. The MA device acquires multi-parameter physiological data from freely moving small animal models, via use of a high bandwidth triaxial accelerometer and temperature sensor to record vital sign information such as the heart and respiration rate and body temperature, and other general features about the animal that include locomotion and body orientation. Each of these features are determined in parallel from subtle motions detected with this platform using the most advanced inertial measurement unit (IMU) technology and transmitted wirelessly and analyzed in real-time using Bluetooth Low Energy (BLE) 5.2 to an external reader system – all isolated to individual subjects within experimental contexts spanning single to multi-animal behaviors. This approach allows other experimental approaches (video tracking, neural recording, etc.) to be directly coupled to the recorded physiological data. By delivering both power and data wirelessly, and by entirely eliminating all external fixtures and physical tethers on the animal, the proposed technology enables chronic physiological recordings in three-dimensional naturalistic environments, from isolated individuals or social groups, in ways that are fundamentally impossible with conventional hardware infrastructure. This low-cost manufacturable system is fully compatible with the NeuroLux radio frequency wireless electronic platform and control software, allowing us to leverage the strengths of an existing commercial platform currently in use worldwide to further advance behavioral and physiological research capabilities.