A miniature kinematic coupling device for mouse head fixation

Abstract

Head-fixation is a common technique in the preparation of subjects for neuroscience experiments. Accurate alignment, stability, and repeatability during fixation provide experimental consistency, thus enabling the subject to return to the same position over time to provide meaningful data. Head restraint systems inspired by kinematic clamps have been developed to allow micron scale repositioning across imaging epochs in rats. Here we report the development of a light-weight, implantable kinematic coupling (clamp) system that is wearable by mice, and enables repeated positioning to submicron accuracy across imaging epochs. This system uses a stainless steel headplate and a Maxwell-style three-groove kinematic mounting system with magnetic force clamping load. Spheres on the dorsal surface of the headplate provide contact points for vee-groove kinematic features machined into a tabletop mount. Evaluation of the clamp using multiphoton microscopy revealed submicron precision in registration accuracy and stability, allowing cellular resolution calcium imaging in awake, behaving mice. These results indicate that miniaturized implantable kinematic clamps for mice could be valuable for future experiments which require repositioning of subjects across time and different instruments. HighlightsO_LIDevelopment of a kinematic clamp for mice for precise repositioning in chronic studies. C_LIO_LIHeadplate and clamp provide stability for cellular resolution imaging during behavior. C_LIO_LIRuby contact features enable submicron registration repeatability. C_LI