Neumann N, Birbaumer N
Institute of Medical Psychology and Behavioural Neurobiology, University of Tuebingen, Gartenstrasse 29, 72074 Tuebingen, Germany.
J Neurol Neurosurg Psychiatry. 2003 Aug;74(8):1117-21. doi: 10.1136/jnnp.74.8.1117.
Direct brain-computer communication uses self regulation of brain potentials to select letters, words, or symbols from a computer menu to re-establish communication in severely paralysed patients. However, not all healthy subjects, or all paralysed patients acquire the skill to self regulate their brain potentials, and predictors of successful learning have not been found yet. Predictors are particularly important, because only successful self regulation will in the end lead to efficient brain-computer communication. This study investigates the question whether initial performance in the self regulation of slow cortical potentials of the brain (SCPs) may be positively correlated to later performance and could thus be used as a predictor.
Five severely paralysed patients diagnosed with amyotrophic lateral sclerosis were trained to produce SCP amplitudes of negative and positive polarity by means of visual feedback and operant conditioning strategies. Performance was measured as percentage of correct SCP amplitude shifts. To determine the relation between initial and later performance in SCP self regulation, Spearman's rank correlations were calculated between maximum and mean performance at the beginning of training (runs 1-30) and mean performance at two later time points (runs 64-93 and 162-191).
Spearman's rank correlations revealed a significant relation between maximum and mean performance in runs 1-30 and mean performance in runs 64-93 (r= 0.9 and 1.0) and maximum and mean performance in runs 1-30 and mean performance in runs 162-191 (r=1.0 and 1.0).
Initial performance in the self regulation of SCP is positively correlated with later performance in severely paralysed patients, and thus represents a useful predictor for efficient brain-computer communication.
直接脑机通信利用脑电位的自我调节从计算机菜单中选择字母、单词或符号，以便在严重瘫痪患者中重新建立沟通。然而，并非所有健康受试者或所有瘫痪患者都能掌握自我调节脑电位的技能，而且尚未找到成功学习的预测因素。预测因素尤为重要，因为只有成功的自我调节最终才能实现高效的脑机通信。本研究探讨了大脑慢皮层电位（SCPs）自我调节的初始表现是否可能与后期表现呈正相关，从而可用作预测指标这一问题。
对五名被诊断为肌萎缩侧索硬化症的严重瘫痪患者进行训练，通过视觉反馈和操作性条件反射策略来产生负极性和正极性的SCP振幅。以正确的SCP振幅变化百分比来衡量表现。为了确定SCP自我调节的初始表现与后期表现之间的关系，计算了训练开始时（第1 - 30次试验）的最大表现和平均表现与两个后期时间点（第64 - 93次试验和第162 - 191次试验）的平均表现之间的斯皮尔曼等级相关性。
斯皮尔曼等级相关性显示，第1 - 30次试验中的最大表现和平均表现与第64 - 93次试验中的平均表现之间存在显著相关性（r = 0.9和1.0），以及第1 - 30次试验中的最大表现和平均表现与第162 - 191次试验中的平均表现之间存在显著相关性（r = 1.0和1.0）。
在严重瘫痪患者中，SCP自我调节的初始表现与后期表现呈正相关，因此是高效脑机通信的一个有用预测指标。
