We describe refinements in optogenetic methods for circuit mapping that enable measurements of functional synaptic connectivity with single neuron resolution. By expanding a two-photon beam in the imaging plane using the temporal focusing method and restricting channelrhodopsin to the soma and proximal dendrites, we are able to reliably evoke action potentials in individual neurons, verify spike generation with GCaMP6s, and determine the presence or absence of synaptic connections with patch-clamp electrophysiological recording.
- Christopher A Baker
- Yishai M Elyada
- Andres Parra-Martin
- McLean Bolton
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health, and all animals were handled according to protocols approved by the Institutional Animal Care and Use Committee of the Max Planck Florida Institute for Neuroscience.
- Michael Häusser, University College London, United Kingdom
© 2016, Baker et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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