This article introduces the Zeffiro interface (ZI) version 2.2 for brain imaging. ZI aims to provide a simple, accessible and multimodal open source platform for finite element method (FEM) based and graphics processing unit (GPU) accelerated forward and inverse computations in the Matlab environment. It allows one to (1) generate a given multi-compartment head model, (2) to evaluate a lead field matrix as well as (3) to invert and analyze a given set of measurements. GPU acceleration is applied in each of the processing stages (1)–(3). In its current configuration, ZI includes forward solvers for electro-/magnetoencephalography (EEG) and linearized electrical impedance tomography (EIT) as well as a set of inverse solvers based on the hierarchical Bayesian model (HBM). We report the results of EEG and EIT inversion tests performed with real and synthetic data, respectively, and demonstrate numerically how the inversion parameters affect the EEG inversion outcome in HBM. The GPU acceleration was found to be essential in the generation of the FE mesh and the LF matrix in order to achieve a reasonable computing time. The code package can be extended in the future based on the directions given in this article.

中文翻译：

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Zeffiro用于电磁脑成像的用户界面：用于Matlab中正向和反向计算的GPU加速FEM工具。

本文介绍了Zeffiro介面（ZI）2.2版，用于大脑成像。ZI旨在为Matlab环境中基于有限元方法（FEM）和图形处理单元（GPU）加速的正向和逆向计算提供一个简单，可访问且多模式的开源平台。它允许（1）生成给定的多隔室头部模型，（2）评估引线场矩阵，以及（3）反转和分析给定的一组测量值。GPU加速应用于每个处理阶段（1）–（3）。在其当前配置中，ZI包括用于电/磁脑电图（EEG）和线性化电阻抗层析成像（EIT）的正向求解器，以及基于分层贝叶斯模型（HBM）的一组反向求解器。我们分别报告了使用真实和综合数据执行的EEG和EIT反演测试的结果，并数值模拟了反演参数如何影响HBM中的EEG反演结果。发现GPU加速对于FE网格和LF矩阵的生成至关重要，以实现合理的计算时间。该代码包可以根据本文给出的说明在将来进行扩展。