"Exploring dendritic integration in awake mice using simultaneous voltage and calcium imaging and electrophysiology.”

Abstract
To investigate dendritic integration in awake mice, we recently developed a technique to simultaneously record dendritic voltage and calcium signalling and somatic activity with high spatio-temporal resolution (Roome and Kuhn 2018). Single cerebellar Purkinje neurons were labelled with voltage sensitive dye ANNINE-6plus and the genetically encoded calcium indicator GCaMP6f, using a chronic cranial window with access port (Roome and Kuhn, 2014) and imaged by two-photon microscopy (line scans at 2 kHz).
By recording subthreshold synaptic inputs localized to dendritic branchlets, rapid (1ms) suprathreshold dendritic spikes and their corresponding calcium signals, and somatic output simultaneously, we examine how spontaneous and sensory-evoked information processing occurs in Purkinje neuron dendrites of awake mice. Purkinje neuron dendritic integration is far more complex, dynamic, and fine scaled than anticipated, even in resting animals.