Fernández T, Harmony T, Rodríguez M, Reyes A, Marosi E, Bernal J
ENEP-IZTACALA Universidad Nacional Autónoma de México.
Int J Neurosci. 1993 Feb;68(3-4):255-61. doi: 10.3109/00207459308994280.
We analyzed test-retest reliability of Absolute (AP) and Relative Power (RP) during rest and during two cognitive tasks: one verbal, the search for a synonym, and the other consisting of mental arithmetic calculations. Under all conditions during the experiment the subjects had their eyes open. The experiment was performed twice, with a month's interval between each trial. Monopolar recordings were obtained in F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6 and Cz vs A1A2. Differences between sessions were observed mainly during rest with eyes open in the lapha band, with higher AP during the first session. During rest it is extremely difficult to control for the state of vigilance, anxiety and thinking. However, during cognitive tasks a more rigid control of the state of vigilance and thinking is obtained. Therefore, AP and RP are very reliable parameters for analyzing EEG during mental tasks. Comparisons between conditions were also made. The only significant differences observed were in delta AP in the second session, with more power during the cognitive tasks in C3 and O2. MANOVAs using the values of AP in the four bands showed significant differences between conditions in C3, C4, P3, O2 and T4. Several factors that may be involved in the origin of delta activity, including eye movements, slow potential shifts and the inhibition of cholinergic projections to the cortex, are discussed.
我们分析了静息状态以及两项认知任务（一项是语言任务，即寻找同义词；另一项是心算任务）期间绝对功率（AP）和相对功率（RP）的重测信度。在实验的所有条件下，受试者均睁眼。实验进行了两次，每次试验间隔一个月。在F3、F4、C3、C4、P3、P4、O1、O2、F7、F8、T3、T4、T5、T6和Cz与A1A2之间进行单极记录。各时段之间的差异主要在睁眼静息状态下的α频段观察到，第一次记录时AP较高。在静息状态下，极难控制警觉、焦虑和思维状态。然而，在认知任务期间，可以更严格地控制警觉和思维状态。因此，AP和RP是分析心理任务期间脑电图的非常可靠的参数。我们还对不同条件进行了比较。观察到的唯一显著差异是第二次记录时的δ频段AP，在C3和O2区域的认知任务期间功率更高。使用四个频段的AP值进行的多变量方差分析显示，C3、C4、P3、O2和T4区域不同条件之间存在显著差异。我们讨论了可能与δ活动起源有关的几个因素，包括眼球运动、慢电位变化以及对皮质胆碱能投射的抑制。
