Matousek M, Wackermann J, Palus M, Berankova A, Albrecht V, Dvorak I
Department of Clinical Neurophysiology, Sahlgrenska Hospital, Göteborg, Sweden.
Neuropsychobiology. 1995;31(1):47-52. doi: 10.1159/000119171.
In contrast to the single-channel dimensional complexity, the global dimensional complexity is calculated from a multichannel EEG. The intention with the method is to measure the spatial distribution of information processing in the brain. The method seems to be of interest in psychopharmacological research, but the interpretation of the results in physiological terms is rather difficult. To get a more detailed information on the physiological significance of the EEG complexity measures, the influence of well-known physiological factors was studied in a group of 14 healthy subjects aged from 1.5 to 61 years. It was found that the correlation dimension was somewhat higher in older individuals, but the correlation with age was not statistically significant. However, the global correlation dimension was significantly lower during full alertness than during drowsiness. These results might reflect the changes in spatial structure of information processing, a high complexity suggesting a 'disorganisation' during drowsiness. As regards the age-dependent changes of the correlation dimension, the spatial 'flexibility' of information processing was also studied, using the differences between the 'alert' and 'drowsy' parts of the same EEG as indicator. It was found that the differences 'drowsy minus alert' were significantly related to age. A plausible interpretation seems to be that the spatial distribution of information processing is more changeable, or more flexible, in adults than in children.
与单通道维度复杂性不同，全局维度复杂性是根据多通道脑电图计算得出的。该方法的目的是测量大脑中信息处理的空间分布。该方法似乎在精神药理学研究中具有一定意义，但从生理学角度对结果进行解释相当困难。为了更详细地了解脑电图复杂性测量的生理学意义，我们对一组14名年龄在1.5岁至61岁之间的健康受试者进行了研究，观察了一些知名生理因素的影响。研究发现，年龄较大者的关联维数略高，但与年龄的相关性无统计学意义。然而，完全清醒时的全局关联维数显著低于困倦时。这些结果可能反映了信息处理空间结构的变化，高复杂性表明困倦时存在“无序”状态。关于关联维数随年龄的变化，我们还利用同一脑电图“清醒”和“困倦”部分之间的差异作为指标，研究了信息处理的空间“灵活性”。结果发现，“困倦减去清醒”的差异与年龄显著相关。一个合理的解释似乎是，成年人信息处理的空间分布比儿童更具可变性，或者说更灵活。
