Mammone Nadia, Morabito Francesco Carlo
DIMET, University of Reggio Calabria, Italy.
Neural Netw. 2008 Sep;21(7):1029-40. doi: 10.1016/j.neunet.2007.09.020. Epub 2008 Feb 29.
Artifacts are disturbances that may occur during signal acquisition and may affect their processing. The aim of this paper is to propose a technique for automatically detecting artifacts from the electroencephalographic (EEG) recordings. In particular, a technique based on both Independent Component Analysis (ICA) to extract artifactual signals and on Renyi's entropy to automatically detect them is presented. This technique is compared to the widely known approach based on ICA and the joint use of kurtosis and Shannon's entropy. The novel processing technique is shown to detect on average 92.6% of the artifactual signals against the average 68.7% of the previous technique on the studied available database. Moreover, Renyi's entropy is shown to be able to detect muscle and very low frequency activity as well as to discriminate them from other kinds of artifacts. In order to achieve an efficient rejection of the artifacts while minimizing the information loss, future efforts will be devoted to the improvement of blind artifact separation from EEG in order to ensure a very efficient isolation of the artifactual activity from any signals deriving from other brain tasks.
伪迹是在信号采集过程中可能出现的干扰,并且可能会影响信号处理。本文的目的是提出一种从脑电图(EEG)记录中自动检测伪迹的技术。具体而言,提出了一种基于独立成分分析(ICA)来提取伪迹信号以及基于雷尼熵来自动检测伪迹的技术。将该技术与基于ICA以及联合使用峰度和香农熵的广为人知的方法进行了比较。在所研究的可用数据库上,新的处理技术平均能检测出92.6%的伪迹信号,而先前技术的平均检测率为68.7%。此外,雷尼熵能够检测肌肉和极低频活动,并将它们与其他类型的伪迹区分开来。为了在最小化信息损失的同时有效地去除伪迹,未来将致力于改进从脑电图中进行盲伪迹分离,以确保能非常有效地将伪迹活动与源自其他脑任务的任何信号隔离开来。