Interneuron networks and cortical dynamics : emulated whisking drives SOM interneurons in the ketamine anesthetized mouse SI neocortex

Abstract

In the core of this thesis I test and confirm the hypothesis that separate classes of interneurons respond differentially to sensory stimulation independent of volitional or other top-down control on the part of the animal. I also test and confirm the hypothesis that, based only on bottom-up sensory stimulation the activity of two major classes of interneurons (adapting Parvalbumin positive and facilitating Somatostatin positive interneurons) predominates during different phases of what corresponds to natural sensing cycles in a behaving rodent. These questions are addressed using an in vivo mouse model with intrinsically fluorescent, but differentiable, interneuron populations combined with 2-photon imaging, Ca²+-sensitive dyes. Anesthesia and electrical control of facial muscles allowed for naturalistic stimulation without the confounds presented by volitional whisking and unknown top-down or behavioral states. Additional chapters in this thesis focus on ancillary work related to computational modeling of neural systems and systems' level perspectives on maturation and disease.