Department of Automatic Engineering, Electronic, Architecture of Computers and Networks, University of Cadiz, Cadiz, Spain.
Int J Neural Syst. 2013 Aug;23(4):1350016. doi: 10.1142/S0129065713500160. Epub 2013 May 26.
Synthetic sounds, tone-beeps, vowels or syllables are typically used in the assessment of attention to auditory stimuli because they evoke a set of well-known event-related potentials, whose characteristics can be statistically contrasted. Such approach rules out the use of stimuli with non-predictable response, such as human speech. In this study we present a procedure based on the robust binary phase-shift keying (BPSK) receiver that permits the real-time detection of selective attention to human speeches in dichotic listening tasks. The goal was achieved by tagging the speeches with two barely-audible tags whose joined EEG response constitutes a reliable BPSK constellation, which can be detected by means of a BPSK receiver. The results confirmed the expected generation of the BPSK constellation by the human auditory system. Also, the bit-error rate and the information transmission rate achieved in the detection of attention fairly followed the expected curves and equations of the standard BPSK receiver. Actually, it was possible to detect attention as well as the estimation a priori of its accuracy based on the signal-to-noise ratio of the BPSK signals. This procedure, which permits the detection of the attention to human speeches, can be of interest for new potential applications, such as brain-computer interfaces, clinical assessment of the attention in real time or for entertainment.
合成声音、音调哔哔声、元音或音节通常用于评估对听觉刺激的注意力，因为它们会引发一系列已知的事件相关电位，其特征可以进行统计对比。这种方法排除了使用无预测反应的刺激，如人类语音。在这项研究中，我们提出了一种基于稳健的二进制相移键控（BPSK）接收器的方法，该方法允许在双耳分听任务中实时检测对人类语音的选择性注意。通过给语音加上两个几乎听不到的标记，达到了这一目标，这两个标记的脑电图响应构成了一个可靠的 BPSK 星座，可以通过 BPSK 接收器来检测。结果证实了人类听觉系统预期产生的 BPSK 星座。此外，在检测注意力时，误比特率和信息传输率都很好地遵循了标准 BPSK 接收器的预期曲线和方程。实际上，根据 BPSK 信号的信噪比，不仅可以检测到注意力，还可以预先估计其准确性。这种允许检测人类语音注意力的方法，可以应用于新的潜在领域，如脑机接口、实时临床注意力评估或娱乐。
