Imaging Somatosensory Cortex in Rodents

Abstract

The rodent somatosensory cortex has been investigated using a range of electrophysiological techniques, from intracellular recordings to electroencephalography. Nonetheless, their accessible location on the dorsal surface of the brain has more recently made the somatosensory areas popular models for the imaging-based investigation of cortical function. In this chapter, we will outline the general principles of two-photon microscopy applied to the functional study of the rodent somatosensory cortex. This technique allows recording the activity of hundreds of individual neurons simultaneously, with single-cell precision and while knowing their relative positions in the brain. We will place particular emphasis on long-term calcium imaging procedures on awake behaving mice and will introduce advantages and limitations of this technique. Our specific aim is to provide the reader with useful information regarding equipment and experimental procedures, from the choice of the calcium indicator to the post hoc analysis of imaging time series.