A tunable local field potentials computer simulator to assess minimal requirements for phase-amplitude cross-frequency-coupling estimation

Network. 2016;27(4):268-288. doi: 10.1080/0954898X.2016.1213440. Epub 2016 Aug 11.

Abstract

The quantitative study of cross-frequency coupling (CFC) is a relevant issue in neuroscience. In local field potentials (LFPs), measured either in the cortex or in the hippocampus, how γ-oscillation amplitude is modulated by changes in θ-rhythms-phase is thought to be important in memory formation. Several methods were proposed to quantify CFC, but reported evidence suggests that experimental parameters affect the results. Therefore, a simulation tool to support the determination of minimal requirements for CFC estimation in order to obtain reliable results is particularly useful. An approach to generate computer-simulated signals having CFC intensity, sweep duration, signal-to-noise ratio (SNR), and multiphasic-coupling tunable by the user has been developed. Its utility has been proved by a study evaluating minimal sweep duration and SNR required for reliable θ-γ CFC estimation from signals simulating LFP measured in the mouse hippocampus. A MATLAB® software was made available to facilitate methodology reproducibility. The analysis of the synthetic LFPs created by the simulator shows how the minimal sweep duration for achieving accurate θ-γ CFC estimates increases as SNR decreases and the number of CFC levels to discriminate increases. In particular, a sufficient reliability in discriminating five different predetermined CFC levels is reached with 35-s sweep with SNR = 20, while SNR = 5 requires at least 140-s sweep.

Keywords: Cross-frequency coupling; local field potential; model; neuroscience; simulation.

MeSH terms

  • Animals
  • Computer Simulation*
  • Hippocampus / physiology*
  • Memory
  • Reproducibility of Results
  • Signal-To-Noise Ratio
  • Theta Rhythm*