Imaging-tools

ANALYTICAL TOOL DEVELOPMENT FOR 1- AND 2-PHOTON CALCIUM IMAGING DATA AND HOLOGRAPHIC STIMULATION

Summary

In the spirit of the Intelligent Machine Brain Interfaces (IMBIT) research building and the recently installed large instrumentation consisting of a two-photon imaging system to obtain neuronal population activity in head-fixed mice navigating through a virtual reality, a holographic unit for the stimulation and manipulation of neuronal activity of selected neuronal populations, and a miniscope for the recording of neuronal activity in freely moving animals, we aim to manipulate memory engrams in the rodent hippocampus and examine their role in the recall of learned information. We will particularly realize two following main aims. First, we aim to examine that hippocampal principal cell associations represent with their activity patterns a given contextual situation by obtaining activity of GCAMP6f-expressing cells in the hippocampus of head-fixed mice navigating through a virtual reality using two-photon imaging and by manipulating their activity using holographic stimulation. Second, we will continue to develop and to test modern calculations and analysis methods, based on machine learning approaches to determine how information is encoded by principal cell associations. We will in particular establish multi-session data analysis for the identification of those neurons representing with their activity patterns a given context on subsequent runs on one day or on subsequent days of exposure to the virtual reality. This analysis is an important requirement for the holographic manipulation of defined cell associations during behavior. Third, we will establish user friendly GUIs to run image alignment across imaging sessions and run statistical models for the identification of active cell assemblies representing a given context. We aim to develop analytical methods to relate neuronal activity to defined behavioral states. Thus, with this project we will markedly contribute to memory neuroscience by addressing the still open question 'how information about space and context is represented in the brain of behaving animals', and by developing state-of-the-art data acquisition and analysis methods, which will be made available to the local IMBIT and broad neuroscience community, and thereby help us all to identify memory traces within cortical networks.