Developing an In Vivo Intracellular Neuronal Recording System for Freely Behaving Small Animals

Electrophysiological intracellular recordings from freely behaving animals can provide information and insights, which have been speculated or cannot be reached by traditional recordings from confined animals. Intracellular recordings can reveal a neuron's intrinsic properties and their communication with other neurons. Utilizing this technology in an awake and socially behaving brain can bring brain research one step further.

In this dissertation, a customized miniature electronics and microdrive assembly is introduced for intracellular recording from small behaving animals. This solution has realized in vivo intracellular recording from freely behaving zebra finches and mice. Also, a new carbon nanotube probe is presented as a surface scanning tip and a neural electrode. With the carbon nanotube probe, intracellular and extracellular neural signals were successfully recorded from mouse brains. Previously, carbon nanotubes have only been used as a coating material on a cell-culturing platform or on a metal based neural electrode. This probe is the first pure carbon nanotube neural electrode without an underlying platform or wire, and it is the first one that has achieved intracellular and extracellular recordings from vertebrate cortical neurons.