Integration of silicon-based neural probes and micro-drive arrays for chronic recording of large populations of neurons in behaving animals

Frédéric Michon,Arno Aarts,Gustaaf Borghs,Fabian Kloosterman,Tobias Holzhammer,Patrick Ruther,Bruce Mcnaughton

doi:10.1088/1741-2560/13/4/046018

Abstract

Objective. Understanding how neuronal assemblies underlie cognitive function is a fundamental question in system neuroscience. It poses the technical challenge to monitor the activity of populations of neurons, potentially widely separated, in relation to behaviour. In this paper, we present a new system which aims at simultaneously recording from a large population of neurons from multiple separated brain regions in freely behaving animals. Approach. The concept of the new device is to combine the benefits of two existing electrophysiological techniques, i.e. the flexibility and modularity of micro-drive arrays and the high sampling ability of electrode-dense silicon probes. Main results. Newly engineered long bendable silicon probes were integrated into a micro-drive array. The resulting device can carry up to 16 independently movable silicon probes, each carrying 16 recording sites. Populations of neurons were recorded simultaneously in multiple cortical and/or hippocampal sites in two freely behaving implanted rats. Significance. Current approaches to monitor neuronal activity either allow to flexibly record from multiple widely separated brain regions (micro-drive arrays) but with a limited sampling density or to provide denser sampling at the expense of a flexible placement in multiple brain regions (neural probes). By combining these two approaches and their benefits, we present an alternative solution for flexible and simultaneous recordings from widely distributed populations of neurons in freely behaving rats.

Highlights

Neuronal assemblies, distributed across multiple brain structures, are the main functional units for information processing in the mammalian brain [1]
A maximum number of 16 bendable silicon-based neural probes could be integrated into a custom designed microdrive array
The separate 3D-printed skull part that is a disposable interface between the micro drivearray and the dental cement is a novel feature in the design that facilitates re-use of the probe array and decreases turnaround time, when combined with proper probe cleaning procedures and optional reconditioning of the electrode sites

Summary

Introduction

Neuronal assemblies, distributed across multiple brain structures, are the main functional units for information processing in the mammalian brain [1]. Hebb’s hypothesis implies that looking at the behaviour of single neurons or the activity from single brain areas independently is not sufficient to understand brain functions. J. Neural Eng. 13 (2016) 046018 neurons that form assemblies. Neural Eng. 13 (2016) 046018 neurons that form assemblies This poses an associated technological challenge: the simultaneous, large-scale readout of brain activity during behaviour in a representative sample of neurons in connected but potentially widely separated brain structures

Methods

Results

Discussion

Conclusion