Abstract
Most excitatory inputs arrive at dendritic spines in a postsynaptic neuron. To understand dendritic information processing, it is critical to scrutinize the spatiotemporal dynamics of synaptic inputs along dendrites. This protocol combines spinning-disk confocal imaging with whole-cell patch-clamp recording to perform wide-field, high-speed optical recording of synaptic inputs in a neuron loaded with a calcium indicator in ex vivo cultured networks. Our protocol enables simultaneous detection of synaptic inputs as calcium signals from hundreds of spines in multiple dendritic branches. For complete details on the use and execution of this protocol, please refer to Takahashi et al. (2012, 2016), Kobayashi et al. (2019), and Ishikawa and Ikegaya (2020).