Accurate tracking and characterization of animal behavior is an integral part of systems neuroscience. In contrast to observing animals in confined laboratory space or head-fixed setups, behavior tracking in large scale environments enables the study of natural behavior without restriction of their sensory-motor experience. In addition, interacting with freely moving animals through closed-loop feedback allows measuring behavioral responses in a controlled manner. Such feedback can be provided through natural sensory inputs or internally by manipulation of sensory or reward circuits in the brain.

Here I will present EthoLoop, a novel framework for studying the neuroethology of freely moving rodents and primates in large scale naturalistic settings. EthoLoop combines real-time optical tracking with wirelessly controlled stimulus/reward devices to enable direct interactions with freely moving animals. The real-time location tracking allows controlling a motorized close-up camera for detailed analysis of behavior through deep learning methods. I will illustrate the versatility of EthoLoop by using the closed-loop feedback feature to reinforce arboreal foraging or the execution of specific behaviors such as jumping from branch to branch. By combining the EthoLoop system with wireless neural recordings I took the initial steps in understanding how volumetric space is represented in the primate brain and illustrate multiple navigation related cells in the hippocampus of freely moving mouse lemurs. Finally, I will present my preliminary results acquired with a battery powered version of the EthoLoop system in the heart of Kirindy forest of western Madagascar.

In parallel I developed BlueBerry, a miniature wireless optogenetic device allowing to integrate internal feedback in closed-loop neuroscience applications. It uses a bluetooth communication protocol and can be programmed to control multiple stimulation channels independently. The light and compact design of BlueBerry makes it an ideal candidate for closed-loop optogenetic applications in freely roaming small animals such as mice. I will demonstrate the capability of BlueBerry for closed-loop applications in two separate scenarios: 1) controlling large scale navigation of freely moving mice by optogenetic stimulation of primary sensory cortex and 2) shaping social dynamics by controlling optogenetic stimulation of the brain’s reward system in situation involving multiple animals.

Taken together, EthoLoop and BlueBerry provide a new generation of interactive tools to conduct neuroethological studies in a reproducible manner.