Yet EEG signals cannot be used directly for limb prostheses, because they depict the average electrical activity of broad populations of neurons; it is difficult to extract from them the fine variations needed to encode precise arm and hand movements.

• 不过EEG讯号不能直接用于义肢，因为该讯号只是一大群神经元的平均放电活性，要从其中抽取出代表手臂及手掌准确动作的细微讯息变化，可是相当困难的事。