The main goal of the Jonas lab is to understand how specific properties of synapses shape higher network functions in the brain. A subgroup of students and postdocs performs subcellular patch-clamp recordings from hippocampal neurons in in vitro slice preparations. In these experiments, we combine recording from presynaptic terminals (a technique pioneered by the PI), dendritic recordings, confocal and 2-photon imaging, and 2-photon uncaging. Another subgroup records from hippocampal neurons in vivo in awake animals situated in a virtual environment on a spherical treadmill or on a linear belt. In these experiments, we combine electrophysiology and optogenetics to obtain information about the synaptic mechanisms of spatial coding. Finally, the Jonas group is not only interested in precise quantitative analysis, but also in modeling the experimental observations at subcellular, cellular, and network level. The famous Hopfield quote “build it, and you understand it“ has become a motto of the research of the entire group.