A Wireless EEG Recording Method for Rat Use inside the Water Maze.

Richard C Pinnell,Ulrich G Hofmann,Robert D Kirch,Rand K Almajidy,Jean C Cassel,Manabu Sakakibara

doi:10.1371/journal.pone.0147730

Abstract

With the continued miniaturisation of portable embedded systems, wireless EEG recording techniques are becoming increasingly prevalent in animal behavioural research. However, in spite of their versatility and portability, they have seldom been used inside water-maze tasks designed for rats. As such, a novel 3D printed implant and waterproof connector is presented, which can facilitate wireless water-maze EEG recordings in freely-moving rats, using a commercial wireless recording system (W32; Multichannel Systems). As well as waterproofing the wireless system, battery, and electrode connector, the implant serves to reduce movement-related artefacts by redistributing movement-related forces away from the electrode connector. This implant/connector was able to successfully record high-quality LFP in the hippocampo-striatal brain regions of rats as they undertook a procedural-learning variant of the double-H water-maze task. Notably, there were no significant performance deficits through its use when compared with a control group across a number of metrics including number of errors and speed of task completion. Taken together, this method can expand the range of measurements that are currently possible in this diverse area of behavioural neuroscience, whilst paving the way for integration with more complex behaviours.

Highlights

The ability to wirelessly record EEG in freely-moving animals has resulted in numerous improvements for behavioural testing, which have otherwise relied on traditional tethered recording techniques
This study has demonstrated a successful method for carrying out wireless recording inside a water maze
In addition to the increased simplicity regarding the recording set-up, the wireless system allowed recordings to take place in the enclosed sections of the maze; which would not have been possible with a typical tethered recording setup

Summary

Introduction

The ability to wirelessly record EEG in freely-moving animals has resulted in numerous improvements for behavioural testing, which have otherwise relied on traditional tethered recording techniques. In addition to their rapid set-up times, wireless systems can be utilised and moved between numerous different arena types, without having to consider customdesigned tethered recording solutions for each different arena configuration; that typically involve swivels, counterweights, rods and commutators. Being able to successfully do so would expand the range of measurements that are possible in this large and diverse area of behavioural neuroscience

Methods

Results

Conclusion