A brain–computer interface (BCI) is a common device for communication between the human brain and a computer. This article investigates the efficiency of using a 3-D interface for BCI machines. For this purpose, the P300 speller, which is a BCI device that enables the user to spell characters on a screen using brain waves, is modified. The classical virtual keyboard of the P300 speller is replaced with 3-D stereoscopic images, which enhances the ergonomic features of the device. Moreover, the flashing paradigm on a 3-D interface can affect the performance of the device in three ways: accuracy, speed, and capacity. This article proposes two different flashing paradigms called the natural 3-D and parallel 2-D interfaces and studied their effects regarding the three mentioned measures. The former flashes the planes in 3-D space, and the latter comprises flashes of parallel keyboards at different 3-D depths. The theoretical analysis of these effects is presented. The results are validated by experimental data obtained from real subjects and were compared with the classical 2-D interface. Both presented keyboards increase the speed of the device, while parallel 2-D has a better total performance than natural 3-D.

中文翻译：

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P300 拼写器 BCI 的 3-D 接口

脑机接口（BCI）是人脑与计算机之间通信的常用设备。本文研究了 BCI 机器使用 3-D 接口的效率。为此，我们修改了 P300 拼写器，它是一种 BCI 设备，使用户能够使用脑电波在屏幕上拼写字符。P300 拼写器的经典虚拟键盘被 3D 立体图像取代，增强了设备的人体工程学特性。此外，3-D 接口上的闪烁范例可以通过三种方式影响设备的性能：准确性、速度和容量。本文提出了两种不同的闪光范式，称为自然 3-D 和并行 2-D 界面，并研究了它们对上述三种措施的影响。前者在 3D 空间中闪烁平面，后者包括在不同 3-D 深度的并行键盘闪烁。介绍了这些影响的理论分析。结果得到了从真实对象获得的实验数据的验证，并与经典的二维界面进行了比较。两种呈现的键盘都提高了设备​​的速度，而并行 2-D 具有比自然 3-D 更好的总体性能。