Long-Range population dynamics of anatomically defined neocortical networks
Abstract
The coordination of activity across neocortical areas is essential for mammalian brain function. Understanding this process requires simultaneous functional measurements across the cortex. However, it has not been possible to dissociate direct cortico-cortical interactions from other sources of neuronal correlations by targeting recordings to neuronal subpopulations that anatomically project between areas. Here, we combined anatomical tracers with a novel multi-area two-photon microscope to perform simultaneous calcium imaging across mouse primary (S1) and secondary (S2) somatosensory whisker cortex during texture discrimination behavior, specifically identifying feedforward and feedback neurons. We observed coordinated S1-S2 activity that is related to motor behaviors such as goal-directed whisking and licking but is not specific to identified projection neurons. However, feedforward and feedback neurons especially participated in inter-areal coordination when motor behavior was paired with whisker-texture touches, suggesting that direct S1-S2 interactions are sensory-dependent. Our results demonstrate specific functional coordination of anatomically-identified projection neurons across sensory cortices.
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Ethics
Animal experimentation: Experimental procedures followed the guidelines of the Veterinary Office of Switzerland and were approved by the Cantonal Veterinary Office in Zurich. Experiments were carried out under the approved licenses 62/2011 and 285/2014.
Copyright
© 2016, Chen 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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