Erlbeck Helena, Mochty Ursula, Kübler Andrea, Real Ruben G L
Institute of Psychology, University of Würzburg, Würzburg, Germany.
Institute of Medical Psychology, University of Tübingen, Tübingen, Germany.
BMC Neurol. 2017 Jan 7;17(1):3. doi: 10.1186/s12883-016-0782-1.
Accidents or neurodegenerative diseases like amyotrophic lateral sclerosis (ALS) can lead to progressing, extensive, and complete paralysis leaving patients aware but unable to communicate (locked-in state). Brain-computer interfaces (BCI) based on electroencephalography represent an important approach to establish communication with these patients. The most common BCI for communication rely on the P300, a positive deflection arising in response to rare events. To foster broader application of BCIs for restoring lost function, also for end-users with impaired vision, we explored whether there were specific time windows during the day in which a P300 driven BCI should be preferably applied.
The present study investigated the influence of time of the day and modality (visual vs. auditory) on P300 amplitude and latency. A sample of 14 patients (end-users) with ALS and 14 healthy age matched volunteers participated in the study and P300 event-related potentials (ERP) were recorded at four different times (10, 12 am, 2, & 4 pm) during the day.
Results indicated no differences in P300 amplitudes or latencies between groups (ALS patients v. healthy participants) or time of measurement. In the auditory condition, latencies were shorter and amplitudes smaller as compared to the visual condition.
Our findings suggest applicability of EEG/BCI sessions in patients with ALS throughout normal waking hours. Future studies using actual BCI systems are needed to generalize these findings with regard to BCI effectiveness/efficiency and other times of day.
事故或诸如肌萎缩侧索硬化症（ALS）等神经退行性疾病可导致进行性、广泛性和完全性瘫痪，使患者意识清醒但无法交流（闭锁状态）。基于脑电图的脑机接口（BCI）是与这些患者建立交流的重要方法。最常见的用于交流的BCI依赖于P300，即对罕见事件产生的正向偏转。为促进BCI在恢复功能丧失方面的更广泛应用，包括视力受损的终端用户，我们探讨了一天中是否存在特定的时间窗口，在此期间更适合应用基于P300的BCI。
本研究调查了一天中的时间和模式（视觉与听觉）对P300波幅和潜伏期的影响。14例ALS患者（终端用户）和14名年龄匹配的健康志愿者参与了研究，并在一天中的四个不同时间（上午10点、12点、下午2点和4点）记录了P300事件相关电位（ERP）。
结果表明，组间（ALS患者与健康参与者）或测量时间在P300波幅或潜伏期上无差异。在听觉条件下，与视觉条件相比，潜伏期更短，波幅更小。
我们的研究结果表明，在整个正常清醒时间内，EEG/BCI会话对ALS患者适用。未来需要使用实际BCI系统的研究，以将这些关于BCI有效性/效率和一天中其他时间的研究结果进行推广。
