Miniaturized Focus-tunable Fluorescence Microscope For Brain Imaging In Freely Behaving Animals

One of the core issues of neuroscience is to explore how the neural activities in the brain created different brain functions and the behaviors generated by these functions.To compare animal behaviors with the spine,neurons and specific brain regions,and to link the activities of neuronal circuits to decipher the basic principles of neural information processing in living free-behaving animals at sub-cells,cells,circuits and higher levels is one of the most leading-edge research in brain neuroscience.It is important for exploring the mechanism of mental illness,advanced brain activity and the combination of brain and machine intelligence.Therefore,the current research urgently needs a microscopic imaging instrument that can accurately and real-time record the neural activity in vivo when the behavior and activity is occurring,so as to figure out the corresponding relationship between the neural activity and the biological emotion or behavior process.Based on biological application scenarios and the development requirements of imaging instruments,we design and implement Miniaturized focus-tunable fluorescence microscope for brain imaging in freely behaving animals in this thesis.The design includes the optical path of the miniature wide-field fluorescence microscope system,the Z-axis zoom module optical path,and the mechanical structure of the miniature microscope system,and achieved the processing and production of the physical prototype and the verification of biological experiments.With the high resolution,high image quality,light weight,small size,and easy to be worn and operated,the system has developed a large-range Z-axis zoom capability of±109?m.The system has the ability of observing the different structures of neurons in a certain range of depth and realized the morphological imaging of dendritic spines.At the same time,in accordance with the application requirements of brain imaging in vivo,the system has carried out a wearable in vivo brain pain cortex calcium imaging experiment and obtained the changes of its fluorescent calcium signal.The development and optimization of this system is expected to become an important research equipment in the field of brain imaging in vivo.It can provide a huge boost for the exploration of the mechanism and treatment of brain mental diseases,which may have broad application prospects in the field of brain science.