Correlations Decrease with Propagation of Spiking Activity in the Mouse Barrel Cortex

Gayathri Nattar Ranganathan,Helmut Joachim Koester

doi:10.3389/fncir.2011.00008

Abstract

Propagation of suprathreshold spiking activity through neuronal populations is important for the function of the central nervous system. Neural correlations have an impact on cortical function particularly on the signaling of information and propagation of spiking activity. Therefore we measured the change in correlations as suprathreshold spiking activity propagated between recurrent neuronal networks of the mammalian cerebral cortex. Using optical methods we recorded spiking activity from large samples of neurons from two neural populations simultaneously. The results indicate that correlations decreased as spiking activity propagated from layer 4 to layer 2/3 in the rodent barrel cortex.

Highlights

Propagation of suprathreshold spiking activity through populations of neurons is important for linking sensory input to behavioral output
Using optical methods we recorded spiking activity from large samples of neurons from two neural populations simultaneously.The results indicate that correlations decreased as spiking activity propagated from layer 4 to layer 2/3 in the rodent barrel cortex
The results indicate that correlations, quantified as the average cross-covariance and complex coherence, decreased as spiking activity propagated from layer 4 (L4) to layer 2/3 (L2/3) in control conditions but increased in the presence of the GABAA receptor antagonist Bicuculline methiodide

Summary

Introduction

Propagation of suprathreshold spiking activity through populations of neurons is important for linking sensory input to behavioral output. Many simulation studies using feed-forward networks have shown that correlations tend to increase as spiking activity propagates through populations of neurons (Diesmann et al, 1999; Reyes, 2003; Kumar et al, 2010; Ozer et al, 2010). Empirical studies conducted in locust auditory system indicated that correlations increased with the propagation of spiking activity (Vogel and Ronacher, 2007). We measured the change in correlations as spiking activity propagated between recurrent networks in a primary sensory cortex, the rodent barrel cortex. To measure the change in correlations as activity propagates requires recording suprathreshold activity from multiple neurons in multiple neuronal populations We achieved this by recording spiking activity from 40 neurons in two populations simultaneously using optical methods. The results indicate that correlations, quantified as the average cross-covariance and complex coherence, decreased as spiking activity propagated from layer 4 (L4) to layer 2/3 (L2/3) in control conditions but increased in the presence of the GABAA receptor antagonist Bicuculline methiodide

Methods

Results

Discussion

Conclusion